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  • Satellite tracking of hawksbill turtles nesting at Buck Island Reef National Monument, US Virgin Islands: Inter-nesting and foraging period movements and migrations
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-15
    Kristen M. Hart, Autumn R. Iverson, Allison M. Benscoter, Ikuko Fujisaki, Michael S. Cherkiss, Clayton Pollock, Ian Lundgren, Zandy Hillis-Starr

    To conserve imperiled marine species, an understanding of high-density use zones is necessary prior to designing and evaluating management strategies that improve their survival. We satellite-tracked turtles captured after nesting at Buck Island Reef National Monument (BIRNM), St. Croix, US Virgin Islands to determine habitat-use patterns of endangered adult female hawksbills (Eretmochelys imbricata). For 31 turtles captured between 2011 and 2014, switching state-space modeling and home range analyses showed that inter-nesting (IN) core-use areas (i.e., 50% kernel density estimates [KDEs]) were 9.6 to 77.7 km2 in area, occupied for 21 to 85 days, and in shallow water (21 of 26 centroids > −10 m). The IN zones overlapped with areas both within the protected borders of BIRNM, and outside BIRNM (32% of turtle-tracking days outside during IN). Turtles migrated to their foraging grounds between July and October with path lengths ranging from 52 to 3524 km; foraging areas included 14 countries. Core-use foraging areas (50% KDEs) where turtles took up residence were 6.3 to 95.4 km2, occupied for 22 to 490 days, with mean centroid depth − 66 m. Our results show previously unknown habitat-use patterns and highlight concentrated areas of use both within and adjacent to a US protected area during the breeding season. Further, our results clearly demonstrate the need for international conservation to protect hawksbills, as migrating turtles crossed between two and eight different jurisdictions. Our results provide critical spatial and temporal information for managers charged with designing strategies to minimize human impact to and maximize survival for this globally imperiled species.

    更新日期:2018-11-16
  • Risks a la carte: Modelling the occurrence and intensity of wolf predation on multiple livestock species
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-16
    Virgínia Pimenta, Inês Barroso, Luigi Boitani, Pedro Beja

    Predation on livestock is a source of human-wildlife conflicts and can undermine the conservation of large carnivores. To design effective mitigation strategies, it is important to understand the determinants of predation across livestock species, which often differ in husbandry practices, vulnerability to predators and economic value. Moreover, attention should be given to both predation occurrence and intensity, because these can have different spatial patterns and predictors. We used spatial risk modelling to quantify factors affecting wolf predation on five livestock species in Portugal. Within the 1619 parishes encompassing the entire wolf range in the country, the national wolf compensation scheme recorded 17,670 predation events in 2009–2015, each involving one or more livestock species: sheep (31.7%), cattle (27.7%), goats (26.8%), horses (14.8%) and donkeys (3.2%). Models built with 2009–2013 data and validated with 2014–2015 data, showed a shared general pattern of predation probability on each species increasing with its own density and proximity to wolf packs. For some species there were positive relations with the density of other livestock species, and with habitat variables such as altitude, and land cover by shrubland and natural pastures. There was also a general pattern for predation intensity on each species increasing with its own density, while proximity to wolf packs had no significant effects. Predation intensity on goats, cattle and horses increased with the use of communal versus private pastures. Our results suggest that although predation may occur wherever wolves coexist with livestock species, high predation intensity is mainly restricted to particular areas where husbandry practices increase the vulnerability of animals, and this is where mitigation efforts should concentrate.

    更新日期:2018-11-16
  • Transmission lines are an under-acknowledged conservation threat to the Brazilian Amazon
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-15
    Jacy L. Hyde, Stephanie A. Bohlman, Denis Valle

    The environmental impacts of energy generation plants, especially those with large dams, have been widely discussed in the Amazon region, but little attention has been paid to the impacts of the associated transmission lines. These impacts are likely to be substantial given the wide geographic extent of the lines and the relatively high forest cover in the traversed areas. Publicly available information about the location and extent of the transmission line network in the Amazon is neither accurate nor current, and its environmental impacts on terrestrial ecosystems have not been assessed on a large scale. This study estimates the scale of the impact of the current and planned transmission and distribution line network using a hand-digitized dataset and the predicted impact area determined from Environmental Impact Assessments.The Legal Amazon region contains 39,625 km of verified transmission and distribution lines, estimated to directly impact 23,467 km2 of land. We find that the transmission line network directly impacts double the area flooded by hydroelectric reservoirs in the Legal Amazon. Of the direct impact area, 5.1% is within protected areas and 10.3% overlaps with intact forest. By 2026, the transmission line network is estimated to grow by 37% in the Legal Amazon, increasing the direct impact to forests by 70% and to protected lands by 29%. Transmission lines are impacting enough land to be considered a serious conservation threat and should be treated as such in research and environmental planning in the Amazon region.

    更新日期:2018-11-16
  • Captive breeding cannot sustain migratory Asian houbara Chlamydotis macqueenii without hunting controls
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-14
    P.M. Dolman, N.J. Collar, R.J. Burnside

    To evaluate the potential contribution of captive breeding to the conservation of exploited migratory Asian houbara Chlamydotis macqueenii, we estimated release numbers required to stabilise a population in a hunting concession (14,300 km2), under scenarios of local licensed hunting and flyway-scale protection. We developed a population model, initially 2350 adult females, re-sampling parameters measured through fieldwork and satellite telemetry, over 1000 iterations. With current flyway-scale unregulated harvest, and without any licensed hunting in the concession, populations declined at 9.4% year−1 (95% CI: −18.9 to 0% year−1); in this scenario a precautionary approach (85% probability λ ≥ 1.0) to population stabilisation required releasing 3100 captive-bred females year−1 (131% of initial wild numbers). A precautionary approach to sustainable hunting of 100 females year−1 required releasing 3600 females year−1 (153% of initial wild numbers); but if interventions reduced flyway-scale hunting/trapping mortality by 60% or 80%, sustaining this quota required releasing 900 or 400 females year−1, 38% and 17% of initial wild numbers, respectively. Parameter uncertainty increased precautionary numbers for release, but even with reduced precaution (50% probability λ ≥ 1.0), sustainable hunting of 100 females year−1 required annual releases of 2200 females (94% wild) without other measures, but 300 (13%) or no (0%) females under scenarios of a 60% or 80% reduction in flyway-scale hunting/trapping. Captive breeding cannot alone sustain migrant populations of wild C. macqueenii because it risks replacement and domestication. Trade and exploitation must be restricted to avoid either extinction or domestication. For exploited populations, supplementation by captive breeding should be used with caution.

    更新日期:2018-11-14
  • Bioinspired models for assessing the importance of transhumance and transboundary management in the conservation of European avian scavengers
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-12
    Antoni Margalida, Pilar Oliva-Vidal, Alfonso Llamas, Mª Àngels Colomer

    The assessment of temporal and spatial availability of food resources is an important prerequisite in developing improved management tools for effective conservation action. It is especially useful in the conservation of avian scavengers inhabiting regions where livestock move on a regular basis (transhumance). Important management decisions can be taken on the basis of theoretical analyses that need to be regularly checked. In this case study, we consider models of Griffon vulture Gyps fulvus, Egyptian vulture Neophron percnopterus and bearded vulture Gypaetus barbatus populations in a part of Spain with one of the highest densities of scavenging birds, and where traditional farming practices remain. We applied bioinspired Population Dynamic P System models (PDP) to assess these species' population trends against the distribution, quantity and availability of carrion for food. We show asymmetries in the availability of food resources, which are substantially higher in summer due to transhumant movements. In the study area, a lack of food resources in winter leads to a seasonal reduction in food supplies to levels unable to meet the energetic requirements of the most abundant vulture species, the Griffon vulture. Our results suggest that regardless of active management (e.g. supplementary feeding sites) and the birds’ use of other potential food resources not included in the model, Griffon vultures are able to find important alternative food resources in more remote areas. We show the importance of variations at spatio-temporal scales in the objective forecasting of population trends, and in the correct application of management actions. Because of the importance of robust assessments for management applications, we discuss the advantages and limitations of ecological modelling for avian scavengers, highlighting the importance of transhumance processes and transboundary approaches.

    更新日期:2018-11-13
  • Multi-scale effects of land cover and urbanization on the habitat suitability of an endangered toad
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-10
    Michael L. Treglia, Adam C. Landon, Robert N. Fisher, Gerard Kyle, Lee A. Fitzgerald

    Habitat degradation, entwined with land cover change, is a major driver of biodiversity loss. Effects of land cover change on species can be direct (when habitat is converted to alternative land cover types) or indirect (when land outside of the species habitat is altered). Hydrologic and ecological connections between terrestrial and aquatic systems are well understood, exemplifying how spatially disparate land cover conditions may influence aquatic habitats, but are rarely examined. We sought to quantify relative effects of land cover at two different but interacting scales on habitat suitability for the endangered arroyo toad (Anaxyrus californicus). Based on an existing distribution model for the arroyo toad and available land cover data, we estimated effects of land cover along streams and within entire watersheds on habitat suitability using structural equation modeling. Relationships between land cover and habitat suitability differed between scales, and broader, watershed-scale conditions influenced land cover along the embedded stream networks. We found anthropogenic development and forest cover at the watershed-scale negatively impacted habitat suitability, but development along stream networks was positively associated with suitability. The positive association between development along streams and habitat suitability may be attributable to increased spatial heterogeneity along urbanized streams, or related factors including policies designed to conserve riparian habitats amidst development. These findings show arroyo toad habitat is influenced by land cover across multiple scales, and can inform conservation of the species. Furthermore, our methodology can help elucidate similar dynamics with other taxa, particularly those reliant on both terrestrial and aquatic environments.

    更新日期:2018-11-12
  • Effectiveness of biodiversity offsets: An assessment of a controversial offset in Perth, Western Australia
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-08
    Sian Thorn, Richard J. Hobbs, Leonie E. Valentine

    Environmental offsets are used increasingly as a conservation tool to balance demands of development and environment but there is little evidence that offsets are effective. Our study assessed the effectiveness of the offset package developed for the Roe Highway Extension, in Western Australia, for Carnaby's black cockatoo, red-tailed black cockatoo and southern brown bandicoot. Black cockatoos were accounted for in the offset requirements, while Southern brown bandicoots were accounted for in the mitigation requirements of the approval but not the offset requirements. The development was cancelled after partial clearing and has not been completed. Pre-development consultant surveys were examined in relation to the offset requirements. Fieldwork was conducted at the offset sites to ground-truth habitat qualities where possible. The offset package was then compared to the principles of Australian Commonwealth and State offset policies. We found the offset package did not completely satisfy Commonwealth or State offset requirements, showed inconsistencies with the policies and produced net loss of environmental value. The offset sites provided 64% of the black cockatoo habitat required by the Commonwealth offset requirements, and were of a lower quality. Similarly, undergrowth vegetation (<1 m; used by southern brown bandicoots) varied between the development and offset sites, indicating the offset proposal approval criteria ‘similar or better quality’ was not met. Like for like is not always required by offset legislation, but it was required in the approval criteria for this development project. The offset sites had previously been deemed unfit for development by the EPA, resulting in little additionality, a fundamental factor in ensuring true gains to compensate for the loss. To improve the suitability of offsets as a conservation tool we strongly encourage a checking process to confirm ecological outcomes of an offset, a contingency plan for if the offset doesn't provide sufficient ecological outcomes, greater consideration of requirements of species affected and stricter adherence to the wider principles of offsets. The use of biodiversity offsets is nearly inevitable given current development policies and processes; however, the application of offsets can be substantially improved to reduce further net loss of environmental value.

    更新日期:2018-11-10
  • Vehicle tracks are predator highways in intact landscapes
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-09
    Keren G. Raiter, Richard J. Hobbs, Hugh P. Possingham, Leonie E. Valentine, Suzanne M. Prober

    Roads and other forms of linear infrastructure are rapidly proliferating worldwide, yet little is known about how roads affect the distribution and abundance of predators, particularly in relatively intact landscapes. We used a combination of motion-sensor cameras and spoor surveys to compare dingo, fox and feral cat activity on unsealed vehicle tracks (hereafter: roads) and up to 3 km away, in relatively intact landscapes of the Great Western Woodlands in south-western Australia. We compared predator activity as indicated by independent sightings and spoor observations, in woodlands and shrublands: vegetation types with contrasting permeabilities. Predator activity was observed between 12 and 261 times more frequently on roads compared with off-road for all species studied. Roads also appeared to affect predator activity up to 2.5 km away. Even poorly formed and abandoned roads concentrated predator activity and affected landscape-scale rates of predator observations. The effect of road proximity on predator activity was non-linear and different between vegetation types for dingoes and cats but not foxes. Our results provide new evidence of the effects of roads on predator activity in surrounding landscapes, with interacting effects of vegetation. They also reinforce previous findings e.g. stronger roads preference displayed by dingoes and foxes, than by cats. Roads and other linear infrastructure have strong effects on predator activity within intact landscapes, although further research is needed to characterise the implications for prey species. Road planning or approvals, as well as habitat restoration programs for threatened species, should account for the effects of roads on predator activity.

    更新日期:2018-11-10
  • Habitat selection in a dynamic seasonal environment: Vegetation composition drives the choice of the breeding habitat for the community of passerines in floodplain grasslands
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-09
    Yoan Fourcade, Aurélien G. Besnard, Edouard Beslot, Stéphanie Hennique, Gilles Mourgaud, Guillaume Berdin, Jean Secondi

    The conservation of grasslands is a concern worldwide as they are threatened by climate change and the expansion of intensive agricultural practices. The management of these areas must take into account the decisional process of habitat selection by individual organisms to identify potential ecological traps or underused habitats. Organisms that live in heterogeneous environments must select their breeding habitat based on cues that reflect habitat quality. In dynamic ecosystems such as grasslands, environmental cues used by individuals should show a strong temporal autocorrelation, such that their characteristics during breeding can be predicted earlier in the season. Our objective was to test if habitat features that explain grassland birds' distribution during the nesting and chick-rearing period could be predicted from the habitat features available on territory settlement. In western France, we analysed the relationships between the occurrence, richness and abundance of four passerine species, and vegetation structure and composition during chick-rearing period. We then analysed the temporal autocorrelation of vegetation features to determine whether the cues used during the settlement period reliably predicted the vegetation features encountered at later stages of breeding. We found that birds selected habitats characterized by a low cover of grasses, but did not respond to the physical structure of vegetation. The composition of vegetation was also the only variable that exhibited temporal autocorrelation over the course of the season, suggesting that individuals may rely on this feature to select optimal breeding habitats. Our results suggest that in dynamic environments, and in the absence of breeding experience or public information, animals can choose their breeding habitat based on a simple assessment of vegetation composition. A detailed knowledge of the underlying drivers of habitat selection is essential to manage habitats, identify potential ecological traps, and enhance the attractiveness of areas especially those under agri-environmental schemes.

    更新日期:2018-11-10
  • Application of isoscapes to determine geographic origin of terrestrial wildlife for conservation and management
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-07
    Hannah B. Vander Zanden, David M. Nelson, Michael B. Wunder, Tara J. Conkling, Todd Katzner

    Accounting for migration and connectivity of mobile species across the annual cycle can present challenges for conservation and management efforts. The use of stable isotope approaches to examine the movements and ecology of wildlife has been widespread over the past two decades. Hydrogen stable isotope (δ2H) composition, in particular, has been frequently used to provide insight into the origin of migratory species, although isotopes of other elements are sometimes used. These intrinsic markers can yield valuable information about distributions of wildlife on a broad scale, with reduced labor and expense compared to tracking and telemetry. Many of the applications of isotopes to migratory species to date have addressed connectivity and origin, and studies in support of conservation biology are less common. In addition, there are few guides for how to best employ these methods for management. Therefore, we provide an overview for the wildlife conservation and management community on how stable isotope methods may be applied to conservation problems and a primer on the process for assigning geographic origins to terrestrial wildlife. We also discuss best practices for employing environmental isoscapes (isotopic distributions across landscapes), rescaling functions, and the assumptions required for assignment to origin while highlighting emerging issues in the modeling process. Finally, we provide example applications to illustrate these principles, and we explore strengths and limitations of this approach in a conservation context.

    更新日期:2018-11-08
  • Distributional shifts in a biodiversity hotspot
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-06
    Lydia Beaudrot, Miguel Acevedo, Jean-Philippe Lessard, Douglas Sheil, Eileen Larney, Patricia Wright, Jorge Ahumada

    Identifying ongoing changes in the distributions of species is critical for understanding and conserving biological diversity. Distributional shifts have been demonstrated in many ecosystems and taxa, yet the extent and nature of these changes remain largely undocumented for tropical forest mammals. Shifts over short time periods can be particularly alarming in areas of the world where mammals are already under threat as a result of human activities. This is the case for Madagascar, an island where deforestation, hunting, invasive species, and other human threats have resulted in the extinction of several endemic species. Here, we ask, are the distributions of Malagasy mammals changing? We test this by modeling local colonization and extinction dynamics, which are the biological processes that produce distributional shifts. We use camera trap data from the TEAM Network for four species along a 570 m elevational gradient in Ranomafana National Park, Madagascar. The endemic Eastern red forest rat (Nesomys rufus) declined in overall occupancy while the non-native bushpig (Potamochoerus larvatus) increased in occupancy overall. The two endemic carnivore species shifted their elevational use: the Malagasy ring-tailed mongoose (Galidia elegans) retracted from higher elevations and the Malagasy civet (Fossa fossana) moved to higher elevations, likely in response to anthropogenic pressures. These results show that shifts are occurring and we can detect them with just six years of data. These results appear near unique in documenting rapid changes in the spatial distributions of tropical forest mammals and provide important information for conservation.

    更新日期:2018-11-07
  • The neglected otters in China: Distribution change in the past 400 years and current conservation status
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-06
    Lu Zhang, Qiaoyun Wang, Li Yang, Fei Li, Bosco Pui Lok Chan, Zhishu Xiao, Sheng Li, Dazhao Song, Zhengji Piao, Pengfei Fan

    Freshwater biodiversity is currently facing critical threats worldwide. As top predators, otters are indicator species of ecosystem health, and flagship species for conservation in freshwater ecosystems. Three otter species – Lutra lutra, Aonyx cinereus, and Lutrogale perspicillata – exist in China. They were once widely distributed but have experienced dramatic decline in the late 20th century, being listed as Class II protected animals in China. We searched in gazetteers, publications, online news, museum specimens, and camera trapping databases, and conducted questionnaire surveys to obtain otter records to reconstruct the historical (1550–1950), recent (1950–2000), and current (post-2000) distribution maps of otters in China. Unlike many other mammal species, otters' range did not contract during 1550–1950. Otters' recent and current distributions were comparable or even surpassed their historical ranges. However, applying rigorous verification criteria, only 57 sites in China were confirmed with otter occurrence since 2000. The potential distribution of L. lutra was mainly on the Tibetan Plateau and in northeast China, whereas only small and sparse patches remained in southeast China, where otters were frequently recorded in historical gazetteers. Although being endangered, otters have been neglected in China, with few research projects and no project funded by National Natural Science Foundation of China. Consequently, even wildlife experts have poor knowledge of otters. Surveys and specific research are urgently needed for otters in China. Public education is also advocated to raise awareness of otter conservation. Without sound information generated from research and urgent conservation actions, otter species will remain severely threatened in China.

    更新日期:2018-11-07
  • Predation risk for boreal woodland caribou in human-modified landscapes: Evidence of wolf spatial responses independent of apparent competition
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-01
    Matthew A. Mumma, Michael P. Gillingham, Katherine L. Parker, Chris J. Johnson, Megan Watters

    Management of wildlife often relies upon understanding mechanisms linking anthropogenic disturbance to population declines. The most-cited mechanism by which disturbance threatens boreal caribou (Rangifer tarandus caribou) is the exacerbation of apparent competition via increases in early successional forage, and subsequent changes in the densities and distributions of other prey species and gray wolves (Canis lupus). An alternative mechanism is the direct alteration of wolf distribution via positive responses by wolves to anthropogenic features. We conducted a mechanistic evaluation of hypotheses explaining human-mediated increases in boreal caribou mortality across northeast British Columbia. We evaluated support for (i) numeric apparent competition (increased prey densities) by evaluating relationships between disturbances, moose (Alces alces) density, and caribou survival. To evaluate (ii) spatial apparent competition (altered prey distribution) and (iii) wolf spatial responses (altered wolf distribution independent of prey), we modeled the relationships between disturbances and indices of caribou-moose and caribou-wolf co-occurrence and then examined predation risk for caribou as a function of co-occurrence. We did not detect any relationships between anthropogenic disturbances, moose density, and caribou survival. Although caribou-moose co-occurrence increased predation risk, we observed both positive and negative relationships between disturbances and caribou-moose co-occurrence. In contrast, caribou-wolf co-occurrence increased predation risk and was positively correlated with anthropogenic linear features. Contrary to other boreal caribou populations, our analyses demonstrate stronger support for the direct effects of anthropogenic linear features on caribou-wolf spatial overlap, leading to greater risk for caribou. Our research highlights the need for region-specific management actions to conserve and recover widely distributed species.

    更新日期:2018-11-05
  • Resource selection in an apex predator and variation in response to local landscape characteristics
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-02
    R.G. Morato, G.M. Connette, J.A. Stabach, R.C. De Paula, K.M.P.M. Ferraz, D.L.Z. Kantek, S.S. Miyazaki, T.D.C. Pereira, L.C. Silva, A. Paviolo, C. De Angelo, M.S. Di Bitetti, P. Cruz, F. Lima, L. Cullen, D.A. Sana, E.E. Ramalho, M.M. Carvalho, P. Leimgruber

    Habitat loss and fragmentation represent major threats for the conservation of apex predators, such as the jaguar (Panthera onca). Investigating species' resource selection behavior in response to landscape alteration is critical for developing relevant conservation management plans. The jaguar is found across a variety of habitats with different gradients of human disturbance, making them a good candidate to study how apex predators respond to increasing intensity of human land use. We developed resource selection models to characterize patterns of jaguar resource selection at two different spatial scales, home range (coarse) and foraging scale (fine). This analysis was based on the largest existing GPS-location dataset for jaguars (n = 40 individuals, n = 87,376 locations), spanning the species' geographic range in Brazil and Argentina. We found that both males and females jaguars exhibited an overall preference for forests and areas close to watercourses at both the home range and foraging scale. At the foraging scale, areas of high livestock density “attracted” male jaguars. We also performed a follow-up analysis to test for context-dependent resource selection (i.e., functional responses) by relating individual behavior to local habitat characteristics. We found that jaguars in heavily-forested landscapes showed strong avoidance of non-forest. Furthermore, we found that only the individuals in closest proximity to watercourses showed positive selection for water. Our results highlight that jaguars display different patterns of resource selection in different areas, demonstrating a considerable ability to use or tolerate a wide variety of different conditions across the species geographic range. This plasticity may allow jaguars to adjust their behavior according to land use changes but also increases human-jaguar conflict and jaguar mortality, especially in areas with high livestock density.

    更新日期:2018-11-05
  • Biodiversity-rich European grasslands: Ancient, forgotten ecosystems
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-01
    Angelica Feurdean, Eszter Ruprecht, Zsolt Molnár, Simon M. Hutchinson, Thomas Hickler
    更新日期:2018-11-05
  • Elephant space-use is not a good predictor of crop-damage
    Biol. Conserv. (IF 4.66) Pub Date : 2018-11-02
    Rocío A. Pozo, Jeremy J. Cusack, Graham McCulloch, Amanda Stronza, Anna Songhurst, Tim Coulson

    Elephant crop-damage is a consequence of interactions between people and elephants that impact people's livelihoods and biodiversity conservation efforts. Conflicts between people and elephants usually occur when there is overlap in elephant and human space-use leading to competition for resources. Therefore, understanding space-use patterns by elephants is key to alleviating negative human-elephant interactions. In the eastern Okavango Panhandle (Botswana), >16,000 people share resources with 18,000 elephants. Using data from 20 GPS-collared elephants, we investigated elephant space-use in relation to landscape variables during the day and night throughout the year and during the dry, wet and crop-damage seasons. We compared elephant space-use and crop-damage occurrence during the crop-damage seasons of 2014–2016. We found that elephant space-use was determined primarily by distance to waterholes and areas away from agricultural fields. However, predicting elephant space-use at the large scale was challenging. In particular, during the crop-damage season when the relationship between crop-damage events and elephant distribution was found to be non-linear. This revealed that areas that elephants frequently use might not be good indicators of the likelihood of crop-damage. Based on our findings, we suggest deterring elephants from peoples' crops at the local scale is the most appropriate strategy for reducing elephant impacts on crops, alongside landscape scale interventions. We encourage future studies to use combinations of spatiotemporal methods, as well as practitioners to focus their efforts at the local scale, protecting elephant corridors, and supporting farmers to collaboratively work to decrease elephant crop-loss.

    更新日期:2018-11-05
  • Functional and geographic components of risk for climate sensitive vertebrates in the Pacific Northwest, USA
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-30
    Meryl C. Mims, Deanna H. Olson, David S. Pilliod, Jason B. Dunham

    Rarity and life history traits inform multiple dimensions of intrinsic risk to climate and environmental change and can help systematically identify at-risk species. We quantified relative geographic rarity (area of occupancy), climate niche breadth, and life history traits for 114 freshwater fishes, amphibians, and reptiles in the U.S. Pacific Northwest. Our approach leveraged presence-only, publicly available data and traits-based inference to evaluate area of occupancy, climate sensitivity (i.e., climate niche breadth), and a Rarity and Climate Sensitivity (RCS) index of all species across multiple geographic extents, grain sizes, and data types. The RCS index was relatively stable across extents, grains, and data types, with climate sensitivity differentiating species with otherwise similar areas of occupancy. We also found that species with sensitivity-associated traits (e.g., long generation time, low fecundity) were not necessarily the same species identified as at-risk with geographical approaches (small range size, small climate niche breadth). Many multispecies assessments using coarse-scale data (e.g., entire range maps or convex-hull approaches) often focus on a single dimension of intrinsic risk; others rely on data-intensive models only applicable to a few well-studied species. What remains is a need for an approach that enables multispecies, multidimensional assessment efforts. This is particularly true at regional scales, where management needs require assessments that are intermediate to coarse- and fine-scale approaches. We demonstrate that by considering multiple dimensions of intrinsic risk to climate change (range size, climate sensitivity, and traits), site-specific locality data may offer a pathway for ensuring vulnerable, understudied species do not go overlooked in conservation.

    更新日期:2018-11-02
  • Projecting further increases in conservation translocations: A Canadian case study
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-30
    Kelly D. Swan, Natasha A. Lloyd, Axel Moehrenschlager

    Conservation actions are critical to mitigating the growing number of threatened species worldwide. Previous studies show a consistent increase in one highly targeted type of conservation action: conservation translocation (i.e. the movement of species for conservation purposes). Will this trend continue? To gain insights into effectiveness and future trends, we examined past and proposed uses of conservation translocation in species recovery efforts in Canada, where species are assessed by the Committee on the Status of Endangered Wildlife in Canada and given legal protection and recovery plans under the Species at Risk Act (SARA). Our review of 541 SARA-listed species indicates 55 have already been translocated, 49 are recommended for translocation, and 99 are under consideration, suggesting at least a doubling in future conservation translocations. Overall, translocation was relevant to recovery efforts for 38% of SARA-listed species. Species in need of translocation overwhelmingly belong to the vascular plants, but relatively few plants have been translocated to date, suggesting capacity and expertise in plant propagation and transplantation will be important. Species listed as Endangered under SARA were most commonly translocated, but the effectiveness of translocations relative to other actions could not be assessed due to insufficient detail in Federal recovery documents. Our finding that conservation translocations are projected to increase substantially in Canada begs the question whether such trends will also occur in other countries, and whether alignment between conservation need, policy direction, scientific planning and financial commitments will be sufficient to meet such demand.

    更新日期:2018-11-02
  • A generalist herbivore requires a wide array of plant species to maintain its populations
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-30
    Satoshi Yamamoto, Kei Uchida

    Generalist herbivores are less susceptible to changes in the plant composition of their habitats than specialists are because generalists can consume a diverse array of plants. However, even generalists exhibit dietary choices, for example because they need to balance their nutritional intake for both growth and reproduction. In this study, we showed that an endangered generalist herbivorous grasshopper (Celes akitanus; Orthoptera: Acrididae) actively chooses which plants to include in its diet. Moreover, we found that grasshopper abundance is correlated with host plant abundance and richness. This grasshopper has been reported to occur mainly in traditionally managed grasslands that harbour more diverse plant species than other, nearby grasslands. To elucidate the links between this grasshopper and plant richness, we surveyed grasshopper abundance in grasslands under traditional and other management practices. Plant DNA barcoding of faecal samples demonstrated that this grasshopper is a generalist herbivore while also showing that it makes active dietary choices. Furthermore, although the grasshopper's host plants occurred in all grasslands, the grasshopper itself was found only in species-rich grasslands. In addition, grasshopper abundance was positively related to the abundance and richness of host plants. Our findings suggest that this endangered herbivore requires a wide array of host plants to maintain its populations.

    更新日期:2018-11-02
  • Nature for whom? How type of beneficiary influences the effectiveness of conservation outreach messages
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-29
    Chelsea Batavia, Jeremy T. Bruskotter, Julia A. Jones, John A. Vucetich, Hannah Gosnell, Michael Paul Nelson

    In recent years the conservation community has engaged in debate over value in nonhuman nature, especially as it relates to motivations for conservation. Many have expressed the assumption that more people are willing to support conservation when emphasis is placed on the human benefits of nonhuman nature, rather than the value of nonhuman nature for its own sake. To test this assumption, we designed an online survey investigating how the type of beneficiary (human, nonhuman, or both) depicted in outreach messages affects two metrics of support: attitudes toward the message and donations for a conservation organization. Each respondent viewed one message highlighting humans, nonhumans, or both as conservation beneficiaries. Predicting that the effect of beneficiary type would depend partially on individual differences, we also measured respondents' moral inclusivity, i.e., the values and beliefs they hold with regard to human and various nonhuman entities. Although beneficiary type did not affect attitudes, we report several key findings for donation. Compared to messages depicting only nonhuman beneficiaries, messages depicting only human beneficiaries were associated with lower likelihood of donation overall and, among less morally inclusive respondents, lower donation amounts. At the same time, messages depicting both human and nonhuman beneficiaries were not associated with more positive donation outcomes than messages depicting only nonhuman beneficiaries. Our results suggest that highlighting humans as conservation beneficiaries may not most effectively generate social support for conservation. Messages advocating the protection of nonhuman nature for its own sake may produce the most consistently positive donation outcomes.

    更新日期:2018-11-02
  • Can the status of pelagic shark populations be determined using simple fishery indicators?
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-30
    Felipe Carvalho, Hui Hua Lee, Kevin R. Piner, Maia Kapur, Shelley C. Clarke

    Calls to develop alternative methods of assessing the population status of pelagic shark populations have increased substantially in recent years. An interim solution has been the development of more subjective evaluation of data series (indicator-based analysis) rather than predictions from complex stock assessment models. This paper examines the reliability of indicators for predicting population status (i.e. whether it has been overfished) and the fishing pressure (i.e. whether overfishing is occurring) of large pelagic sharks, based on these fishery indicator trends alone. We simulate a variety of large pelagic shark populations under different exploitation scenarios using life history parameters, and measurable fishery indicators information (catch-per-unit of effort - CPUE; and average length - AL). Our simulation results, designed to be generalized (via sampling of realistic distributions) but based loosely on the shortfin mako shark, showed that the reliability of fishery indicators for establishing population status is dependent upon the length of the time series analyzed. These caveats are critical to the proper evaluation of population trajectories that underlie the most important conservation decisions being made for sharks today.

    更新日期:2018-11-02
  • Identifying priority conservation areas for birds associated to endangered Neotropical dry forests
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-31
    David A. Prieto-Torres, Javier Nori, Octavio R. Rojas-Soto

    Neotropical dry forests (NDF) are widely distributed and possess important levels of species richness and endemism; however, they are considered a highly endangered ecosystem. Today, the protected areas network (PAs) located within NDF covers <10% of the total forests' extent; and it's still unknown if PAs adequately represent its biodiversity. Thus, we selected 695 bird species associated to NDF and used ZONATION software to assess the species distribution's representativeness within the PAs network. Additionally, we defined priority conservation areas to strategically expand the current PAs considering the most important human pressures. Current PAs cover only 8.4% of NDF and represent on average ~10% of the total distribution of avifauna inhabiting these forests. Approximately 19% of NDF's birds possess <5% of their distribution represented in PAs, from which ~13% have <1% of their ranges protected. Further, ~77% of the most-priority species (i.e. with restricted range and categorized as threatened) possess <10% of their distribution protected. However, our results pointed out great possibilities to improve the picture. By considering our prioritization, the protection coverage would increase to 17% to match the Aichi targets and would substantially increase the representativeness values, covering on average >36% the ranges of all species and, particularly, 62% for the most-priority species. Priority conservation areas identified are mainly distributed in Peru (23.1%), Brazil (21.3%), Ecuador (18.8%), and Bolivia (11.4%). Our novel results represent an important step to guide future establishment of new and efficient conservation areas across the NDF.

    更新日期:2018-11-02
  • Giant anteater (Myrmecophaga tridactyla) conservation in Brazil: Analysing the relative effects of fragmentation and mortality due to roads
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-26
    Fernando A.S. Pinto, Alex Bager, Anthony P. Clevenger, Clara Grilo

    Road networks can have serious ecological consequences for many species, mainly through habitat fragmentation and mortality due to collisions with vehicles. One example of a species impacted by roads is the giant anteater (Myrmecophaga tridactyla), currently listed as Vulnerable by IUCN. Here we analysed the relative effect of fragmentation and mortality due to roads on giant anteater populations and show the critical areas for their persistence in Brazil. We estimated minimum patch size and maximum road density to evaluate the impact of the road network and observed road-kills on this species. We explored different scenarios by varying values of dispersal capacity to estimate the minimum patch size, and also of population densities to estimate maximum road density for giant anteater persistence. Our findings indicated that the minimum patch size can be from 498 to 247 km2 and the maximum road density can vary between 0.21 and 0.55 km/km2 in pessimist and optimistic scenarios, respectively. In Brazil, habitat fragmentation seemed to have a major impact over giant anteater populations. Habitat fragmentation due to roads seemed to have a more negative effect than mortality due to collisions with vehicles. Critical areas for the species persistence can represent 32% of its range in the optimistic scenario with 18% of suitable patches below the minimum size and 0.1% above the maximum road density. This study provides insights and implications for road networks on giant anteater populations in Brazil and guidance on road density and patch size thresholds for land managers and road agencies charged with planning ecologically sustainable roads in Brazil.

    更新日期:2018-10-27
  • Simple biopsy modification to collect muscle samples from free-swimming sharks
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-25
    Lauren Meyer, Andrew Fox, Charlie Huveneers
    更新日期:2018-10-26
  • Multiple facets of rarity among rain forest trees in the Western Ghats of India
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-22
    Priya Davidar, François Munoz, Jean-Philippe Puyravaud, D. Mohandass, V.S. Ramachandran

    We collated data on the latitudinal, elevation and seasonality ranges, local densities, stature and dispersal mode of 514 evergreen tree species (≥10 cm girth at breast height), including 317 endemics, from the rain forests of the Western Ghats (WG) of India using two complementary databases, (i) 68 tree inventory plots, and (ii) the Atlas of Endemics. We tested the hypotheses that (i) regional rarity would be associated with local rarity and narrower ecological amplitudes, (ii) shorter and mechanically dispersed trees would be rarer, (iii) higher proportion of endemic species would be rare (iv) regionally wide ranging species would be locally rare, and localised species would be denser, (v) families with single species would be relicts in this biome, (vi) larger families would have a higher proportion of rare and endemic species. We used Atlas records in a generalised least square model acknowledging phylogenetic relationships, to test hypotheses (i) to (ii), and non parametric tests for (iii) to (vi). We identified rare species using binary cut-offs and compared these with IUCN threat status. Rarity was associated with (i) narrower ecological amplitudes and shorter stature, independent of phylogeny, (ii) 18 wide ranging and locally sparse, 41 narrow ranging and locally dense species, (iii) relict species and families, (iv) larger families. Rare species were more likely to be threatened, but 39% were not evaluated. We identified zones of rare endemics to help with conservation planning. The WG rain forests have a unique evolutionary history and potential that require increased conservation measures.

    更新日期:2018-10-26
  • Conventional MPAs are not as effective as community co-managed areas in conserving top-down control in the Gulf of California
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-19
    Karol Ulate, Teresa Alcoverro, Rohan Arthur, Octavio Aburto-Oropeza, Carlos Sánchez, Leonardo Huato-Soberanis

    While undeniably successful in protecting nearshore marine ecosystems from overfishing, conventional marine reserves often impinge on the livelihoods of dependent coastal communities. Community co-managed areas may guarantee considerably more equity, but it is unclear if they can be as effective as conventional reserves in conserving critical trophic functions. We evaluated the effectiveness of different management regimes in the Gulf of California on fish biomass and echinoderm assemblages as proxies of key ecosystem processes on rocky shores. We compared multiple sites in a mixed (multi-use areas with regulated extraction) and core (no-extraction) federally-managed areas, a military MPA (where strict patrolling ensures no extraction), a co-managed reserve where government and communities are equally responsible, and unrestricted-access areas (non MPA). Fish biomass was higher in the military reserve and the community co-managed area reserve; echinoderm numbers were very low at these locations suggesting that they were strongly controlled by top-down processes. In contrast, federally-controlled reserves were virtually no different from unrestricted-access areas in numbers or composition of fish and echinoderms. Although federal managed reserves are the most common management regime across the Gulf, our data shows that they are highly ineffective in protecting ecosystem function. The relative effectiveness of co-managed reserves in this region suggests that fishers are more willing to comply when they have a stake in decision-making. Coastal conservation can benefit greatly by drawing from a wider suite of management options that engage local communities as key participants in the managing marine diversity and critical ecosystem functions.

    更新日期:2018-10-26
  • Text and data mining of social media to map wildlife recreation activity
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-24
    Graham G. Monkman, Michel J. Kaiser, Kieran Hyder

    Mining of social media has been shown to be a useful tool for social and biological research (e.g. tracking disease out breaks). This article outlines an accessible approach to the use of text and data mining (TDM) of social media to gather information on wildlife recreation activity. The spatio-temporal distribution of the shore based recreational European seabass (Dicentrarchus labrax) fishery in Wales is used as an example. Public online user generated content was mined using automated scraping. Data on fisher activity and fish sizes were extracted and then georeferenced by matching place names to a custom compiled gazetteer. Numbers of trips and spatio-temporal trends in the distribution of activity and catches were estimated. Prosecution was higher in summer than winter, and gear use and trip durations were consistent during the period 2002–13. Comparisons of TDM with existing surveys showed higher levels of activity and catch, and shorter mean trip durations were estimated using TDM. Monthly activity correlated closely with existing survey data. Spatial and temporal data agreed qualitatively with expert knowledge. This article showed that TDM can be used to describe a wildlife recreation activity, but use of TDM to derive unbiased population level estimates is challenging and more work is required to develop appropriate methods to correct for bias. These methods required no expertise in natural language processing or machine learning, a working knowledge of programming (e.g. in Python or R) is all that is needed to apply this approach. The opportunities to use TDM will increase with the continuing adoption of smartphones in emerging economies and developing nations and is of may be of particular utility where other data is unavailable.

    更新日期:2018-10-26
  • Long term amphibian monitoring at wetlands lacks power to detect population trends
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-22
    C.H. Greenberg, S.J. Zarnoch, J.D. Austin

    Amphibians are declining worldwide due to habitat destruction, disease, and environmental stressors. Extremely variable breeding populations and a paucity of long-term monitoring data limits rigorous testing of amphibian population trends, or bias associated with sampling regimes. We used 24 years of continuous trapping data to compare annual probability of presence, and population trends and statistical power for six species among seven wetlands using five sampling scenarios (SS) based on the interval and span of years analyzed. Richness within a year and wetland ranged 29–89% of total species captured there (all years), and 27–82% of total species captured during the study (all years, pooled wetlands). SS had little effect on probability of presence for most common species but did for less common species. Population trends were inconsistently significant or nonsignificant among wetlands within SSs, and among SSs within the same wetlands. The direction (+/−) of trends among wetlands and scenarios for a species generally agreed, but not always. Low statistical power for virtually all population trend estimates, including the All-years SS indicated results were inconclusive. Juvenile recruitment was correlated with adult populations in some subsequent years for four of the six species. We illustrate how probability of presence and population trend estimates can differ among similar wetlands within a landscape, and according to the span, or subset of years sampled. Our results indicate that amphibian monitoring at wetlands cannot conclusively gauge population trends for breeding populations that fluctuate widely among wetlands and from year to year.

    更新日期:2018-10-26
  • Novel landscape elements within natural gas fields increase densities but not fitness of an important songbird nest predator
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-23
    Lindsey E. Sanders, Anna D. Chalfoun

    Identifying the elements within human-altered landscapes most associated with population and community changes is critical for conservation and management of sensitive species. We investigated which features of habitat change from natural gas development best explained the density of deer mice (Peromyscus maniculatus), an important nest predator of declining sagebrush-obligate songbirds. During 2014–2016, we quantified the spatial extent of habitat change (well pads, roads, and reclaimed areas [i.e., reseeded soils]) surrounding 12 sites spanning two natural gas fields in Wyoming, USA. We further tested whether the altered plant communities within reclaimed areas provided benefits to deer mice, by assessing multiple fitness indices. Deer mouse density increased with surrounding reclaimed area. Powder tracking and dietary analyses confirmed that mice moved through and consumed plant species found exclusively within reclaimed areas. Concomitant fitness metrics of mice, however, were neutrally or negatively related to the amount of surrounding reclaimed area. Mice therefore did not derive any apparent fitness benefits associated with living near reclaimed areas, despite the presence of novel food resources, indicating that increased abundance may be a product of mice dispersing toward reseeded soils. Our study contributes mechanistic insights into the complexities of how human-induced changes to landscapes can influence community dynamics. Minimizing total habitat disturbed during construction, expediting reclamation practices, and using only native and regionally-local seed mixes would likely help minimize increases in synanthropic rodent predators within energy fields. More efficient restoration of disturbed habitat, moreover, may help ameliorate altered predator-prey relationships that affect the success of sensitive species.

    更新日期:2018-10-26
  • 更新日期:2018-10-18
  • Deadwood enrichment combining integrative and segregative conservation elements enhances biodiversity of multiple taxa in managed forests
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-13
    Inken Doerfler, Martin M. Gossner, Jörg Müller, Sebastian Seibold, Wolfgang W. Weisser

    Integrative management strategies that simultaneously aim for wood production and biodiversity conservation are considered crucial to protect biodiversity of forest species outside protected areas. In this study, we evaluated whether deadwood enrichment as an integrative strategy at a scale of 17,000 ha resulted in enhanced biodiversity of saproxylic and non-saproxylic taxa eight years after the implementation of the strategy. The strategy included active deadwood enrichment with harvest remnants, retention of deadwood, and nature forest reserves areas. The analysis was based on data on the occurrence of plants, fungi, beetles, true bugs and birds from directly before and after the implementation of the strategy. The implementation of the strategy resulted in an increase in the deadwood amount by an average of 90 ± 40 m3 ha−1 (mean ± SE) over this period. While deadwood amounts doubled in production forests (+90%), they increased even more in nature forest reserves (+160%). Multidiversity (species density of all taxa) increased with an increase in deadwood amount; this was a result of an increase in the multidiversity of saproxylic species as the non-saproxylic multidiversity did not respond. Among single taxon groups, fungal and beetle species density responded positively to the increase in deadwood amount, especially when only saproxylic species were analysed. Importantly, this effect was not only found in the nature forest reserves, but also in the production forests. We thus conclude that active deadwood enrichment in production forests and nature forest reserves is a promising tool to rapidly promote the protection of forest biodiversity.

    更新日期:2018-10-15
  • Demographic responses to climate variation depend on spatial- and life history-differentiation at multiple scales
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-13
    Matthew Tye, Johan P. Dahlgren, Dag-Inge Øien, Asbjørn Moen, Nina Sletvold

    Long-term demographic data are needed for detailed viability analyses of populations threatened by climate change, but the infeasibility of obtaining such data makes it urgent to assess whether demographic responses to climatic variation can be generalized across populations and species. We used 32 years of demographic data on four species of closely related orchids (genera Dactylorhiza and Gymnadenia), replicated in a coastal and an inland region in central Norway, to test how demographic responses to climate varied among geographical regions and species. We fit generalized linear mixed models (GLMMs) to study climate effects on vital rates and included GLMMs as components in matrix models to examine climate effects on population dynamics. We found that, overall, vital rates and population growth rates of the eight populations responded independently to variation in both temperature and rainfall. Only probability of flowering showed expected regional differentiation in response to climate, despite notable regional climatic differences. Other vital rate – climate relationships were structured by species or a combination of both region and species. The weak clustering of demographic responses to climate variation by species and region demonstrates that effects of climatic variation can strongly depend on variation in local habitat and life history, even among closely related populations occupying similar niches. This highlights the difficulty in transferring data from closely related and/or located populations for viability analyses and for models predicting range shifts, and a general need to account for among-population variation in demographic responses to develop successful conservation and management plans.

    更新日期:2018-10-14
  • Situating the Half-Earth proposal in distributive justice: Conditions for just conservation
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-12
    Anna Wienhues

    The Half-Earth proposal (or ‘Nature Needs Half’) was put forward as an answer to the current sixth mass extinction crisis on Earth and sparked a debate with disagreement on empirical and normative questions. In this paper I focus on the so far undertheorised normative debate and will provide some conditions that would need to be fulfilled in order for the Half-Earth proposal to serve justice. As I will illustrate, to even begin with situating the Half-Earth proposal within an account of justice rests on an extensive rebuilding of our understanding of justice and many dimensions of justice have to be addressed before it is possible to determine whether the proposal could be regarded as all-things-considered just. I will start by focusing on the question of what would constitute a just global distribution of habitat by introducing the conceptual framework of distributive ecological justice – i.e., the notion that also nonhuman beings can have justice claims to certain ‘goods’ – and put it into conversation with considerations of environmental justice between humans. The upshot is that if a range of empirical and normative conditions are fulfilled, then the proposal can embody a distributively just compromise between ecological and environmental justice.

    更新日期:2018-10-14
  • Effects of persistent energy-related brine contamination on amphibian abundance in national wildlife refuge wetlands
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-11
    Blake R. Hossack, Kelly L. Smalling, Chauncey W. Anderson, Todd M. Preston, Isabelle M. Cozzarelli, R. Ken Honeycutt

    To inform sustainable energy development, it is important to understand the ecological effects of historical and current production practices and the persistence of those effects. The Williston Basin is one of North America's largest oil production areas and overlaps the Prairie Pothole Region, an area densely populated with wetlands that provide important wildlife habitat. Although historical disposal practices that released chloride-rich waters (brines) produced during oil extraction into the environment are no longer used, brine spills still occur frequently. We sampled 33 wetlands for three amphibian species in Montana and North Dakota during 2015–2017, primarily on National Wildlife Refuges, and used N-mixture models to determine how abundance varied with evidence of brine contamination. To provide insight into effects of historical versus contemporary contamination, we also estimated the association of well density and age with water quality and amphibian abundance. Abundance of boreal chorus frog (Pseudacris maculata) larvae declined most rapidly in response to increased chloride (range: 0.04–17,500 mg/L), followed by the northern leopard frog (Lithobates [Rana] pipiens) and barred tiger salamander (Ambystoma mavortium). Water quality and population- and community-level abundance of amphibians were more strongly related to nearby wells (≤800 m) installed before 1982 than to wells installed since 1982. These results suggest historical brine management practices were the primary driver of contamination and reduced amphibian abundance in wetlands we sampled, reflecting multi-decadal ecological effects. These persistent effects also underscore the critical need for tools to restore landscapes affected by brine contamination.

    更新日期:2018-10-11
  • Are farming and birds irreconcilable? A 21-year study of bustard nesting ecology in intensive agroecosystems
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-10
    Vincent Bretagnolle, Leopold Denonfoux, Alexandre Villers

    Farmland landscapes in developed countries have undergone major habitat changes over the past 60 years leading to the decline of many species. Of these, the little bustard, a medium-sized, long-lived, ground nesting bird, has declined by 95% in France over the last 35 years. Here we present the results of a 21 year survey of the nesting ecology of this elusive species, analyzing 157 breeding attempts, the largest data set ever collated for this species. Females had a strong preference for meadows for breeding, yet this habitat only represented 14% overall habitat. Alfalfa alone accounted for 50% of nest locations. However, apart from vegetation type, females did not show any other pattern of habitat selection (vegetation height, nest position within field, field under agri-environmental contract-AES-). In addition, the laying period was extremely extended, spanning almost 3 months. We did not detect any strong effect of crop, date or whether the nesting field was in AES or not, on clutch size, egg size and egg-laying date. However, there were long-term changes in breeding phenology (females breed earlier than 20 years ago), and selection of vegetation between years and within years. Hatching success was very low (about half of the broods were destroyed by farm work), and both fecundity and productivity per female were found to be approximately one third of the values expected for a stable population. Overall, nesting females of Little Bustards select meadows in regard to their availability, but do not show any particular preference within meadows' vegetation structure or height. We show that in such system, meadows act as ecological traps, and furthermore, because females do not appear selective, it is impossible to manage meadows in order to limit this trap. We finally analyze whether the land-sharing AESs can conserve this species in intensive arable systems and conclude that the land sharing may not be sustainable. We discuss our results in light of the alternative of land sparing, and suggest that this is probably a better fit for the conservation of large-bodied bird species given their ecological constraints (large home ranges, presence of semi-natural landscape components and freedom from human interference).

    更新日期:2018-10-11
  • Foregrounding ecojustice in conservation
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-10
    Haydn Washington, Guillaume Chapron, Helen Kopnina, Patrick Curry, Joe Gray, John J. Piccolo

    Justice for nature remains a confused term. In recent decades justice has predominantly been limited to humanity, with a strong focus on social justice, and its spin-off – environmental justice for people. We first examine the formal rationale for ecocentrism and ecological ethics, as this underpins attitudes towards justice for nature, and show how justice for nature has been affected by concerns about dualisms and by strong anthropocentric bias. We next consider the traditional meaning of social justice, alongside the recent move by some scholars to push justice for nature into social justice, effectively weakening any move to place ecojustice centre-stage. This, we argue, is both unethical and doomed to failure as a strategy to protect life on Earth. The dominant meaning of ‘environmental justice’ – in essence, justice for humans in regard to environmental issues – is also explored. We next discuss what ecological justice (ecojustice) is, and how academia has ignored it for many decades. The charge of ecojustice being ‘antihuman’ is refuted. We argue that distributive justice can also apply to nature, including an ethic of bio-proportionality, and also consider how to reconcile social justice and ecojustice, arguing that ecojustice must now be foregrounded to ensure effective conservation. After suggesting a ‘Framework for implementing ecojustice’ for conservation practitioners, we conclude by urging academia to foreground ecojustice.

    更新日期:2018-10-11
  • Lemurs in a dying forest: Factors influencing lemur diversity and distribution in forest remnants of north-eastern Madagascar
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-08
    Dominik Schüßler, Ute Radespiel, Jonah Henri Ratsimbazafy, Jasmin Mantilla-Contreras

    A majority of Madagascar's iconic lemurs (Primates, Strepsirrhini) is threatened with extinction due to anthropogenic activities like land use change (deforestation) and bushmeat hunting. We used a multivariate approach combining land cover mapping, vegetation/degradation monitoring, the degree of anthropogenic disturbance and the status of forest protection by the local community to model their impact on lemur diversity, population densities and encounter rates within a rural area of lowland rain forest in north-eastern Madagascar. High mean annual deforestation rates (2.4%) were calculated since 1990, resulting in a landscape of small and isolated forest fragments. A limited number of eight lemur species belonging to five lemur families were encountered. Diurnal species were absent, while cathemeral lemurs avoided human disturbance. Small and nocturnal species were relatively abundant. Overall lemur diversity was best explained by forest size and a combination of disturbance and hunting. Encounter rates of three nocturnal taxa were influenced by forest size and habitat degradation. Community-level forest protection had no effect on lemur diversity, but coincided with lower levels of habitat degradation. Lemur population sizes were relatively small and only few forests remain that offer suitable habitats for viable populations. We highly recommend external conservation NGOs to support local forest management by improving the existing community-based approach. Actions should include expansion of protected habitats to increase population connectivity (reforestation) and to decrease lemur disturbance by villagers. Without external support, the last remaining forest habitats will be devastated within a few years resulting in the local extinction of most lemur populations.

    更新日期:2018-10-09
  • Little owls in big landscapes: Informing conservation using multi-level resource selection functions
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-08
    Julien Fattebert, Vanja Michel, Patrick Scherler, Beat Naef-Daenzer, Pietro Milanesi, Martin U. Grüebler

    Habitat models are fundamental tools for designing evidence-based conservation measures, particularly for locating sites with high potential for promoting a species' recolonisation and occupancy. However, it remains challenging to respond to both the need for large-scale general rules, and for fine-scale information concurrently. Multi-level habitat models provide all-in-one surfaces that explicitly account for conditional dependencies among single-level selection probabilities. We integrated occurrence data obtained from citizen-science species observation data with radio-tracking data to develop multi-level resource selection functions for the little owl (Athene noctua), a species of conservation concern in Central Europe. The results of our habitat selection analyses confirmed that suitable little owl habitat is located in widely open agricultural landscapes that often exist in the vicinity of human settlements. We mapped habitats at fine resolution (40 × 40 m) over an area covering 77,313 km2 in Switzerland and Baden-Württemberg, Germany. We validated the models with external out-of-sample data, and we demonstrated good predictive ability and transferability over the broad landscape. Overall, a fifth of the modelled landscape was estimated to be suitable for little owls. Habitat suitability scores in Switzerland were generally lower than in Baden-Württemberg due to higher elevation, fewer orchards, and more forest patches. Extant populations currently occupy c. 15% of the potential suitable habitats in Baden-Württemberg, and 2% in Switzerland, suggesting that considerable space for recolonisation is available. However, while Baden-Württemberg offers vast open landscapes, lowlands in Switzerland show narrow swaths of habitat along valleys and lakes. We showed that the simultaneous integration of different levels of habitat selection behaviour into a multi-level habitat suitability map creates a promising tool for conservation planning of endangered species over large geographical areas. Our multi-level model allowed for identification of both large-scale habitat suitability patterns to develop conservation strategies, and fine-scale clusters of high quality habitats where conservation measures can be applied at once, thereby increasing relevance of such all-in-one habitat maps for policy makers, wildlife managers and conservations practitioners alike.

    更新日期:2018-10-09
  • Behavioral responses to, and fitness consequences from, an invasive species are life-stage dependent in a threatened native fish
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-08
    Timothy R. Brown, Rhys A. Coleman, Stephen E. Swearer, Robin Hale

    Native wildlife are impacted by invasive species in numerous ways and will be more vulnerable if they cannot recognize the threat posed by an invader. Impacts, however, are generally assessed for a single life stage and without consideration of behavioral responses. This limits knowledge of the mechanisms underpinning the threats of invaders and the responses that could help or hinder native animals to mitigate this threat. We conducted a series of experiments to examine if the threat of an invader and behavioral responses by a native animal are life-stage dependent. Our focal species were a widespread invasive (Gambusia holbrooki) and a threatened native Australian freshwater fish (Galaxiella pusilla). We show that the threat of, and behavioral responses to, the invader vary across life-cycle stages. Gambusia holbrooki had different effects on G. pusilla: inhibiting reproduction and consuming larvae but not eating eggs or reducing adult growth and survival. Although larval G. pusilla avoided visual cues from G. holbrooki, native predators and conspecific adults, they did not avoid olfactory cues from G. holbrooki, which is maladaptive considering the predation risk. In addition, adult G. pusilla did not avoid any G. holbrooki cues, providing further evidence of maladaptive behavior. Our study is one of the first comprehensive evaluations of how the threats of an invader to a native species, as well as the responses to this threat, are life-stage dependent. We use our empirical results to develop a general framework for understanding the mechanisms by which invasives threaten native biota, and highlight how this can be used to help assess and mitigate the threat of invaders.

    更新日期:2018-10-09
  • Direct modelling of limited migration improves projected distributions of Himalayan amphibians under climate change
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-06
    Barkha Subba, Sandeep Sen, Gudasalamani Ravikanth, Michael Peter Nobis

    Amphibians are one of the most vulnerable taxa at risk of rapid decline under climate change. Here, we evaluated the impact of different migration constraints on projected future distributions of four high elevation frogs, belonging to the genus Scutiger, in the Eastern Himalaya. We explored differences between the output of conventional models assuming no or unlimited migration versus models considering plausible migration rates to ascertain future species distributions under climate change. Distributions of the four Scutiger species, namely S. boulengeri, S. glandulatus, S. sikimmesis and S. tuberculatus, based on field data and other sources were modelled using MaxEnt and projected for three future time periods (2021–2040; 2041–2060; 2061–2080) under the relatively ambitious RCP4.5 and the more pessimistic RCP8.5 climate change scenarios using three global circulation models. Projected species distributions were compared at different spatial resolutions (1 km, 5 km and 10 km) and for five assumptions about species migration: (1) no migration; (2–4) low, medium and high migration abilities using the KISSMig model; and (5) unlimited migration. Without migration, the projected future distribution of all four species showed a significant decrease of −15% to −64% by 2080. In contrast, three out of the four study species were projected to expand their distribution under unlimited migration scenarios. Models with more realistic migration rates, however, demonstrated considerable deviance from both no migration and unlimited migration scenarios. These results were consistent across models with different spatial resolutions. Our study shows that ignoring realistic migration constraints can lead to ineffective conservation measures by overestimating the future distribution of Himalayan amphibians. The proposed framework can be used to project more realistic ranges of future species distributions by considering the accessibility of future suitable areas, a key factor for species persistence under climate change.

    更新日期:2018-10-08
  • Using citizen science data in integrated population models to inform conservation
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-06
    Orin J. Robinson, Viviana Ruiz-Gutierrez, Daniel Fink, Robert J. Meese, Marcel Holyoak, Evan G. Cooch

    Analysis of animal population status and change are core elements of ecological research and critical for prioritizing conservation actions for at-risk species. Traditionally, count-based data from structured surveys have been the main source of information used to estimate trends and changes in populations. In the past decade, advances in integrated population models (IPMs) have allowed these data to be combined with other data sources (e.g., observations of marked individuals). IPMs have allowed researchers to determine the direction and magnitude of population trends and to identify underlying mechanisms contributing to population change. For many species, life-history characteristics (e.g., colonial breeding, low site-fidelity), low abundance and/or low detection probability make it difficult to collect sufficient data; thus, IPMs for these species are difficult to employ. Citizen science data may be useful in such situations and enable conservation biologists to combine data from many sources into robust estimates of population trajectories. IPM's represent a possible way of combining diverse data sources, but their practicality for incorporating citizen science data has not been investigated. Here, we used count data from eBird to estimate population trends for a species of conservation concern, the tricolored blackbird (Agelaius tricolor). We combined estimates of relative abundance with banding and nesting data. Our joint estimation of demographic rates allowed us to evaluate their individual contributions to the population growth rate. Our analysis suggests that the California tricolored blackbird population suffered a mean decline of 34% from 2007 to 2016. Mean annual adult survival ranged from 0.28 to 0.93 for females and 0.17 to 0.78 for males. Mean juvenile survival across years was 0.21 (95% CI = 0.0007–0.49), fecundity (as nestlings per nest) ranged from 0.46 to 1.27. We suggest that investments in increasing reproductive success and recruitment are the most likely conservation strategies to increase the population. Here, the extensive survey efforts of citizen scientists aided the employment of IPMs to inform conservation efforts for tricolored blackbirds.

    更新日期:2018-10-08
  • Selecting surrogate species for connectivity conservation
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-04
    Margaux Meurant, Andrew Gonzalez, Aggeliki Doxa, Cécile H. Albert

    Habitat loss and fragmentation impede the movement of animals across landscapes causing biodiversity change. One strategy to counter these effects is to protect and restore habitat quality and connectivity for a diversity of species. How should surrogate species be selected to represent a diversity of needs from a larger species pool? Using a recent method to prioritize multispecies habitat networks, we tested how the selection of surrogate species affects prioritization outcomes. We ran prioritization schemes using subsets of N (N = 0, 1, 3, 5, 7, 9) species selected from a 14-species reference set. Selection was based on different concepts of surrogate species: umbrella, taxonomy, habitat diversity, movement diversity, movement and habitat diversity. Prioritization outputs were compared to the 14-species set for their effectiveness and comprehensiveness at retaining habitat quality and connectivity criteria, and for their spatial congruence. We show that species-based surrogates perform better than habitat-based surrogates and that a moderate number of species (5–7) might be sufficient to capture the needs of a broader species pool for one habitat type (forest). However, how species are selected matters as much as how many. The best performing approach is to select species representing a diversity of habitat and/or movement needs. Umbrella or taxonomy-based selections were less effective and comprehensive. Our results can guide the selection of surrogate species when designing a prioritization plan for regional connectivity conservation. We recommend favoring systematic trait-based species selection over single-species, umbrella or taxonomy-based selections. When a proper species-based surrogate approach cannot be done, a habitat-based surrogate approach might still be a useful alternative.

    更新日期:2018-10-05
  • Spatially and temporally targeted suppression of despotic noisy miners has conservation benefits for highly mobile and threatened woodland birds
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-05
    Ross Crates, Aleks Terauds, Laura Rayner, Dejan Stojanovic, Robert Heinsohn, Colin Wilkie, Matthew Webb

    Interactive effects of habitat loss and interspecific competition are major threats to global biodiversity. Managing despotic competitors in modified landscapes is a conservation priority, but implementing actions to benefit rare and highly mobile species is challenging. In Australia, overabundance of hyperaggressive noisy miners following woodland fragmentation and degradation is a key threatening process given their impact on songbirds including the nomadic, critically endangered regent honeyeater. Recent studies have found rapid noisy miner recolonization following their experimental removal, questioning the efficacy of miner removal as a conservation measure. We estimated the relative habitat saturation of noisy miners at a hotspot of threatened bird diversity. We then experimentally removed 350 noisy miners and assessed the effect of this removal on subsequent noisy miner abundance, relative to a control area. We monitored the occurrence of noisy miners near regent honeyeater nests and modelled the effect of noisy miner removal on songbird populations. Noisy miner removal significantly decreased noisy miner abundance throughout the breeding season, when 15–18 regent honeyeaters nested in the miner removal area. Songbird abundance and species richness increased significantly in the miner removal area, relative to the control area. We provide a rare example of how spatially and temporally targeted preventative action can reduce threats for nomadic and highly threatened species during breeding and prevent ongoing avian diversity loss more broadly.

    更新日期:2018-10-05
  • Medicinal plant harvesting, sustainability and cultivation in South Africa
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-05
    A.S. van Wyk, G. Prinsloo

    Concerns regarding the conservation of medicinal plant species are receiving much attention due to overharvesting and exploitation. Medicinal plant harvesting is a global concern as plants are the source of the majority of medicines, either traditional or western, in the world. Millions of U.S. dollars of plant material are being exported annually from developing countries to developed countries. The challenge in developing countries is that, apart from the exports, the majority of people in those countries still use medicinal plant material for their basic healthcare needs. Biodiversity loss is therefore a significant challenge. This review focuses on South Africa as a developing country in which traditional medicines are highly valued, but also engages in exports of medicinal plant material to developed countries. Medicinal plant harvesting, with reference to suppliers of medicinal plant material, customary knowledge and the drivers of increased harvesting rates in South Africa is discussed. General aspects of sustainability and the causes of unsustainable medicinal plant harvesting, as well as cultivation to increase medicinal plant populations referring to its advantages and disadvantages and the challenges regarding cultivation of medicinal plant species for the medicinal plant trade market are reviewed. The shift from a cultural method of survival to a competitive trade business, South Africa's legislation regulating the management of natural environments, legislation compliance and the regulation of African traditional medicine are also reviewed.

    更新日期:2018-10-05
  • Legal obligations regarding populations on the verge of extinction in Europe: Conservation, Restoration, Recolonization, Reintroduction
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-03
    José Vicente López-Bao, Floor Fleurke, Guillaume Chapron, Arie Trouwborst

    After more than two decades of implementation of the Habitats Directive (Directive 92/43/EEC), some fundamental aspects of the directive are still unclear, and subject to interpretive uncertainty, which limit its correct implementation. For example, obligations for Member States in situations where a protected population has almost, or has just, gone extinct are unclear. The isolated and protected population of wolves (Canis lupus) in the Sierra Morena region in Spain – the only wolf population in the southern half of the Iberian Peninsula – has been steadily declining to the point where it is doubtful whether any wolves are left. Using this illustrative example, we provide clarifications on the obligations by Member States in situations where populations are on the verge of extinction. Our analysis shows that Articles 6 and 12 of the Habitats Directive require Member States to restore populations that are quasi extinct. From a legal perspective, even the complete extinction of the species would not exonerate Member States from its obligations regarding the species in the Natura 2000 sites concerned. In this line, we argue that the Spanish authorities should not wait with recolonization, reinforcement and/or reintroduction actions until the complete absence of wolves in the Sierra Morena is conclusively proven. Two scenarios appear to meet legal requirements: i) active reinforcement/reintroduction, or ii) an active and effective policy towards a rapid natural recolonization of Sierra Morena by northern wolves. However, based on the observed wolf trends in Spain and Portugal during the past five decades, a reconnection between northern and Sierra Morena wolves seems unlikely in the foreseeable future even if actively promoted. Considering the urgency of actions required to avoid that this population will be the first wolf population to become extinct in Europe in modern times, in order to comply with European obligations, the adopting and carrying out a reintroduction/reinforcement scheme to restore the Sierra Morena wolf population is required. Such a scheme needs to be accompanied by a comprehensive enforcement plan to assure that reintroduced wolves will thrive.

    更新日期:2018-10-04
  • A fence runs through it: A call for greater attention to the influence of fences on wildlife and ecosystems
    Biol. Conserv. (IF 4.66) Pub Date : 2018-10-01
    Andrew F. Jakes, Paul F. Jones, L. Christine Paige, Renee G. Seidler, Marcel P. Huijser

    Fencing is a nearly ubiquitous infrastructure that influences landscapes across space and time, and the impact of fences on wildlife and ecosystems is of global concern. Yet the prevalence and commonness of fences has contributed to their “invisibility” and a lack of attention in research and conservation, resulting in a scarcity of empirical data regarding their effects. Stakeholders, including scientists, conservationists, resource managers, and private landholders, have limited understanding of how fences affect individual animals, populations, or ecosystem processes. Because fences are largely unmapped and undocumented, we do not know their full spatial extent, nor do we fully comprehend the interactions of fences with wild species, whether positive or negative. To better understand and manage fence effects on wildlife and ecosystems, we advocate for an expanded effort to examine all aspects of fence ecology: the empirical investigation of the interactions between fences, wildlife, ecosystems, and societal needs. We first illustrate the global prevalence of fencing, and outline fence function and common designs. Second, we review the pros and cons of fencing relative to wildlife conservation. Lastly, we identify knowledge gaps and suggest research needs in fence ecology. We hope to inspire fellow scientists and conservationists to “see” and study fences as a broad-scale infrastructure that has widespread influence. Once we better understand the influences and cumulative effects of fences, we can develop and implement practical solutions for sustaining wildlife and ecosystems in balance with social needs.

    更新日期:2018-10-02
  • Off-the-shelf GPS technology to inform marine protected areas for marine turtles
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-28
    Robin T.E. Snape, Phil J. Bradshaw, Annette C. Broderick, Wayne J. Fuller, Kimberley L. Stokes, Brendan J. Godley

    The financial expense of tracking solutions often impedes effective characterisation of habitat use in threatened marine megavertebrates. Yet some of these taxa predictably aggregate at coastal breeding sites, providing conservation opportunities. Toward a low-cost solution for tracking marine megavertebrates, we trial conventional GPS data loggers against Argos satellite transmitters for assessing inter-nesting habitat use of marine turtles. Devices were attached to green (Chelonia mydas) and loggerhead (Caretta caretta) turtles nesting at a study site in Cyprus, where patrol teams were in place to retrieve GPS loggers from turtles returning to lay subsequent clutches. GPS tracking revealed loggerhead turtles to predominantly use areas outside the boundaries of an MPA proposed for the region, while both species under-used much of the MPA area. Due to high location error, Argos data were considered unsuitable for such fine-scale assessments (all location classes except Z were included in our analysis). However, Argos tracking showed half the loggerhead turtles sampled also nested outside of the patrolled study area, demonstrating connectivity with other proposed MPAs. This was not accounted for by GPS tracking, because females exhibiting this behaviour rarely returned to the study beach, precluding GPS retrieval, thus, demonstrating the power of remote data access. The low-cost GPS technology could be considered in similar cases, where recapture is likely and where funding barriers preclude the use of Argos-relay fast-acquisition GPS technology. In combining the accuracy GPS and the continuity of Argos, the latter provides the best solution in most scenarios, but at far greater cost.

    更新日期:2018-09-29
  • Is large good enough? Evaluating and improving representation of ecoregions and habitat types in the European Union's protected area network Natura 2000
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-27
    Anke Müller, Uwe A. Schneider, Kerstin Jantke

    Natura 2000, the largest protected area network worldwide, covers 18.2% of the European Union's terrestrial area. Thereby, the network surpasses the goal of the Convention on Biological Diversity's Aichi target 11 to protect 17% of the land area by 2020. However, Aichi target 11 also calls for protected area networks to be ecologically representative. Here, we analyzed the coverage of 43 ecoregions in the terrestrial Natura 2000 estate. To simulate cost-efficient closing of gaps in the current system, we applied a linear programming model that solves the minimum set conservation problem of expanding the Natura 2000 network to achieve 10% ecoregion representation. As Natura 2000 sites are designated for habitat types and species listed on the annexes of the Habitats and Birds directives, we included 226 habitat types as a further biodiversity surrogate in the optimization. We found six ecoregions that currently do not meet the 10% representation target. To close these gaps, an additional 15,187 km2 (0.35% of the European Union's land territory) would be required. Simultaneously, representation of 21 habitat types could be increased. The United Kingdom would have to contribute more than half of the additional area, followed by Estonia, Latvia, France, and Italy. To protect biodiversity effectively and to comply with international conservation targets such as Aichi target 11, we recommend continuous evaluation and improvement also of already well-established protected area networks.

    更新日期:2018-09-28
  • A method for identifying suitable biodiversity offset sites and its application to reclamation of coastal wetlands in China
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-26
    Shuling Yu, Baoshan Cui, Philip Gibbons

    We explored the potential for biodiversity offsetting to be applied in regions with considerable development pressure. We developed a method to identify suitable locations for restoration offsets and applied this to coastal reclamation in the Yellow River Delta region of China, an internationally important area for migratory birds, but in which 44% of wetlands have been reclaimed. We evaluated the suitability of sites for offsetting based on their ecological similarity to development sites, the potential of biota to migrate between sites and socio-economic criteria. We predicted that 60–100% of all reclamation in the Yellow River Delta between 1980 and 2015 could be theoretically offset provided no constraints were placed on where offsetting occurs within the region. However, where potential offset sites were constrained to areas with high suitability only 8–15% of historic coastal reclamation could be offset. Spatial options for offsetting also declined where time lags before restoration were longer. Our results indicated that strict in-kind biodiversity offsetting becomes increasingly challenging in highly modified landscapes because of a lack of spatial options for offsets and a tendency for potential offset sites to be dissimilar to the habitat that originally occurred on developed sites in these landscapes. Policies that seek to enable development within highly modified landscapes by providing flexibility for offsetting in space and time risk providing offsets that are ecologically dissimilar from development sites and have limited capacity for biota to migrate to or from them. Our methodology can be used as a planning tool to indicate the level of development within a landscape or region beyond which no net loss is unlikely to be feasible.

    更新日期:2018-09-27
  • Elevated potential for intraspecific competition in territorial carnivores occupying fragmented landscapes
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-25
    Pranav Chanchani, Brian D. Gerber, Barry R. Noon

    The distribution of mammals is determined by a suite of endogenous and exogenous factors. In territorial, polygynous species like tigers (Panthera tigris), males often center their space-use around female territories, repelling competitors from these areas. Competition among males for females leads to increased mortality of both sexes and infanticide of unrelated cubs, which can lead to population declines. We hypothesized that increased territorial overlap among adult male tigers and elevated levels of inter and intra-sex competition would be manifest in populations with male-biased adult sex ratios (ASR). We also assessed whether inter-sex variation in adult survival or degree of habitat connectivity resulted in skewed ASR. We evaluated these hypotheses using camera trap data from three tiger populations occupying habitat patches with varying levels of connectivity and ASRs. Data were analyzed using multi-state occupancy models, where states were defined as habitat use by one or more male tigers in sites with and without female use. As predicted, in populations with male-biased or even ASR we found evidence for increased spatial overlap between male tigers, particularly pronounced in areas adjacent to female territories. Given parity in adult survival, habitat fragmentation likely caused male-biased ASR. Our results suggest that the persistence of small tiger populations in habitat patches with male-biased ASR may be significantly compromised by behavior-mediated endogenous demographic processes that are often overlooked. In habitat fragments with pronounced male biased ASR, population recovery of territorial carnivores may require timely supplementation of individuals to compensate for population losses from intraspecific competition.

    更新日期:2018-09-26
  • Is the impact of loggings in the last primeval lowland forest in Europe underestimated? The conservation issues of Białowieża Forest
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-25
    Grzegorz Mikusiński, Jakub Witold Bubnicki, Marcin Churski, Dorota Czeszczewik, Wiesław Walankiewicz, Dries P.J. Kuijper

    Loggings in biodiversity hot-spots are perceived as very serious threat to forest species and habitats of high conservation interest. In this paper we scrutinize the spatial impacts of recent loggings in the Polish part of the renowned Białowieża Forest being the last remaining area of lowland temperate forest with a primeval character in Europe with the status of World Heritage and Natura 2000 site. The loggings have been applied in order to cope with the outbreak of the spruce bark beetle Ips typographus. We used satellite images to perform cover change detection analysis that delineated areas being logged in Białowieża Forest between July 2015 and June 2018. Next, we assessed the extent of forest loss in areas with different management regimes as well as landscape-scale impacts. The total area of detected clear-cuts amounted to at least 675 ha, including 229 ha of old-growth stands. Assuming a buffer of 100 m from the edge of cleared forest patches, the cumulative direct and indirect impact of recent logging activities was estimated to amount to at least 4073 ha of affected forest. Logging activities resulted in a 26% increase in fragmentation in the entire Natura 2000 area. We argue that the ecological impact of logging extends beyond the logged areas by modifying the landscape structure and affecting ecosystem functioning on a landscape scale. As such, the recent salvage loggings in the Białowieża Forest clearly damaged the conservation value of this precious area, not in the least by increasing its fragmentation. To avoid further degradation, we strongly argue for allowing natural tree regeneration on clear cuts and also for the extension of Białowieża National Park to cover the entire forested area.

    更新日期:2018-09-26
  • Mapping threats to wilderness character in the National Wilderness Preservation System
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-22
    James Tricker, Peter Landres

    The National Wilderness Preservation System in the United States provides the greatest level of protection for the ecological and social values of lands held in trust for future generations. Although designated wilderness is the cornerstone of the US conservation portfolio, designation alone doesn't assure the protection of these areas, which are degraded by threats both inside and external to the area. This paper describes new methods for quantifying the location and cumulative magnitude of threats to wilderness, allowing agency managers and the public to evaluate whether the legal mandate from the 1964 Wilderness Act to “preserve wilderness character” is being upheld. These new methods have also been used in developing wilderness stewardship plans and analyzing the potential effects of proposed projects that would degrade wilderness character. The methods described here were developed and tested in seven wildernesses in a variety of ecological, geographic, and administrative settings, and are directly applicable to evaluating threats and improving the management of all 110 million acres of designated wilderness in the United States, as well as all areas that are increasingly recognized internationally as wilderness.

    更新日期:2018-09-25
  • Post-war recovery of the African lion in response to large-scale ecosystem restoration
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-22
    Paola Bouley, Michael Poulos, Rui Branco, Neil H. Carter

    We present data from the first, long-term study underway of a recovering population of indigenous, free-ranging Panthera leo in Gorongosa National Park (GNP), Mozambique. GNP is undergoing post-war recovery and large-scale ecological restoration under a 25-year private-governmental partnership – the “Gorongosa Project (GP),” – offering a rare opportunity to elucidate the long-term recovery dynamics of a population of lion in response to strategic conservation interventions. GNP forms a core part of the greater Gorongosa-Marromeu Lion Conservation Unit which is designated as a “potential lion stronghold.” Within the Park we established an intensive study area of 1100 km2 encompassing prime areas of herbivore productivity. Between 2012 and 2016, 104 lions were documented and 6 prides and 7 males or coalitions in our study area were satellite-collared and intensively monitored. We describe seasonal male and female home-ranges, prey utilization, estimated versus predicted lion densities in relation to recovering herbivore biomass, and anthropogenic factors limiting the population's full recovery potential. The dominant factor observed to be negatively impacting the population was top-down and anthropogenic in the form of by-catch by wire snares and steel-jaw traps set by bushmeat hunters. These findings have since resulted in tangible and measurable interventions to reduce these impacts and resultant future datasets will elucidate detailed demography and how management interventions impacted the trajectory of large-carnivore recovery.

    更新日期:2018-09-25
  • Saproxylic biodiversity and decomposition rate decrease with small-scale isolation of tree hollows
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-22
    Laia Mestre, Nicklas Jansson, Thomas Ranius

    Biodiversity is fundamental for ecosystem functioning, but little is known about how function responds to biodiversity loss following habitat disturbance in natural systems. Due to the global decay of veteran trees, many associated saproxylic (i.e. deadwood-dependent) insects are considered threatened. Nevertheless, the role of habitat spatial configuration on saproxylic insect biodiversity and dead wood decomposition is poorly understood. We performed a six-year landscape-scale colonization experiment on saproxylic beetles inhabiting hollow oaks, using boxes filled with wood mould as standardized habitat patches. We placed boxes either on a hollow tree or on another tree 61–324 m from the hollows, thereby creating two habitat isolation levels. We quantified wood mould decay and biodiversity in the boxes, measuring species richness, total abundances and community-weighted mean of body mass (CWM) as an index of community functional composition. Isolation had a persistent negative effect on primary consumer biodiversity, but it only impaired decay at the beginning of the experiment. All effects were independent of landscape-level (500-m radius) habitat amount surrounding the boxes. Wood mould decay was mediated by CWM of primary consumers. Therefore function was driven by the body masses of the dominant primary consumer species but not by species numbers (richness) or individual numbers (abundance). Our experiment shows that small-scale habitat isolation leads to biodiversity loss and reduced function and indicates that habitats created by conservation efforts will be used by more saproxylic species if located within sites with a high density of veteran trees.

    更新日期:2018-09-25
  • Assessing consumer trends and illegal activity by monitoring the online wildlife trade
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-22
    Yik-Hei Sung, Jonathan J. Fong

    Wildlife ranks the fourth among illegally traded items. The insatiable market demand for wildlife products directly threatens plants, animals and their natural habitats. Identifying illegal trade and understanding consumer trends is important for the conservation of overexploited species. The internet and social media have emerged as popular platforms for wildlife trade, and surveying these marketplaces is an important tool for conservation. Due to their high demand and high value, we choose turtles as a case study to demonstrate the usefulness of monitoring the online trade. We collected data (species, number and price) on the sale of live turtles from a Hong Kong-based internet forum for 36 months (September 2013–August 2016) to assess the scale of the trade, identify potential illegal trade and investigate factors that influence prices. We recorded 14,360 individuals of 136 species, including 67 threatened species. Of the 77 species sold that are listed in CITES appendices, 36% were likely illegally traded as they had neither possession licenses under Hong Kong law nor CITES import records. Turtles with the highest prices tended to be critically endangered species, wild-caught or those with special morphological forms. Sale of hybrid turtles of 38 “species/varieties” occurred in 4% of all sale posts. Our survey of the online trade in Hong Kong discovered important trends of sale price and consumer preference, collected baseline data for enforcing trade regulations and highlighted likely illegal trade of turtles. We encourage similar studies for other highly traded wildlife to be incorporated into integrative approaches for conservation management.

    更新日期:2018-09-25
  • Modelling the spread and control of cherry guava on Lord Howe Island
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-22
    Christopher M. Baker, Sue Bower, Elena Tartaglia, Michael Bode, Hank Bower, Robert L. Pressey

    Effectively controlling invasive species on islands is a critical aspect of global conservation. Having the potential to outcompete or consume native species, it is particularly important to remove them from islands harbouring unique flora and fauna. Lord Howe Island, a World Heritage listed area to the east of the Australian mainland, is in the midst of a long-term weed management project, where the most prolific invasive species is cherry guava, with over 700,000 plants removed so far. In such projects, it is critical to have a good understanding of the invasion dynamics and removal process to have reliable estimates of project timeline and success, and to ensure the best removal strategies are being utilised. In this paper we model cherry guava growth, spread and removal on Lord Howe Island, fitting our model to 12 years of removal data. Our mean estimate is that there are 102,091 plants remaining on the island, which will take approximately 25 years to remove at current levels of eradication effort. Altering the strategy to search every year, rather than biennially, reduces the eradication time to 20 years, which falls within the project target, while also decreasing the total search effort. However, simply increasing search effort to finish faster actually increases the total eradication effort. This shows that the benefits of making careful adjustments to a strategy can far out-weight the benefit of simply investing more money into control. This project exemplifies how high-quality removal record-keeping can be used to generate models that provide important long-term forecasts of project success and suggest effective strategic improvements.

    更新日期:2018-09-25
  • The cost of enforcing a marine protected area to achieve ecological targets for the recovery of fish biomass
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-22
    Christopher J. Brown, Brett Parker, Gabby N. Ahmadia, Rizya Ardiwijaya, Purwanto, Edward T. Game

    Protected areas are the primary management tool for conserving ecosystems, yet their intended outcomes may often be compromised by poaching. Consequently, many protected areas are ineffective ‘paper parks’ that contribute little towards conserving ecosystems. Poaching can be prevented through enforcement and engaging with community members so they support protected areas. It is not clear how much needs to be spent on enforcement and engagement to ensure they are frequent enough to be effective at conserving biodiversity. We develop models of enforcement against illegal fishing in marine protected areas. We apply the models to data on fishing rates and fish biomass from a marine protected area in Raja Ampat, Indonesia and explore how frequent enforcement patrols need to be to achieve targets for coral reef fish biomass. Achieving pristine levels of reef fish biomass required almost year-round enforcement of the protected area. Surveillance of the protected area may also be enhanced if local fishers who support the reserve report on poaching. The opportunity for local fishing boats to participate in surveillance was too small for it to have much benefit for total reef fish biomass, which increases slowly. However, specific functional groups of fish have much higher population growth rates and their biomass was predicted to increase markedly with community surveillance. We conclude that budgets for park management must balance the cost of conducting frequent patrols against supporting alternative activities, like education to build community support. Optimized budgets will be much more likely to achieve ecological targets for recovering fish biomasses and will contribute to fiscal sustainability of protected areas.

    更新日期:2018-09-25
  • Waterbird communities adjust to climate warming according to conservation policy and species protection status
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-19
    Elie Gaget, Thomas Galewski, Fréderic Jiguet, Isabelle Le Viol

    Climate change is one of the strongest biodiversity threats. Worse still, the impact of multiple anthropic stressors on species dynamics could complicate adaptation to temperature increase. International conservation policies aim to protect ecosystems against anthropic pressures, but their ability to facilitate adaptation to climate change has yet to be assessed. Using wetland bird monitoring surveys, we evaluated the differences at the country scale of community adjustment to temperature increase of wintering waterbird communities (145 species) according to the implementation of the two main western Palearctic international conservation policies (Bern Convention and Birds Directive) in the Mediterranean basin (2786 sites, 22 countries) over a 22-year period. We showed that thermic community composition increases over time in countries which have enforced conservation policies. We found that strictly protected species under the Birds Directive and the Bern Convention contributed more to this community adjustment than the not strictly protected species. The mechanism results from a population increase in protected warm-dwelling species but not from a decline in cold-dwelling species. This study supports the ability of international conservation policies to mitigate the effect of climate change on animal communities.

    更新日期:2018-09-20
  • Survivors or reinvaders? Intraspecific priority effect masks reinvasion potential
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-19
    Florian Pichlmueller, James C. Russell

    Invasions of alien species on islands cause serious deleterious effects on native species through predation and competition often to the point of extinction. Where eradication is not possible ongoing control programs are the only alternative. Following control efforts there are risks of both recolonisation from survivors and reinvasion from neighbouring populations. Successful pest control efforts at such sites depend heavily on two rules of eradication: (1) individuals have to be removed faster than the growth rate and (2) reinvasion must be close to zero. We used a small near-shore island as a ‘microcosm’ to test whether both these rules could be met. We applied a molecular genetic approach to assess genetic differentiation of a ship rat (Rattus rattus) population on a nearshore island with the adjacent mainland population and investigated metapopulation dynamics and pest control success. Tissue samples from Goat Island, New Zealand, from three consecutive years were genotyped at 14 microsatellite loci and compared with the mainland populations. We showed moderate genetic differentiation between the two populations despite their close proximity and demonstrated that rats were neither being removed faster than they bred nor was reinvasion able to be managed close to zero. Furthermore, population reduction on the island counter-productively facilitated establishment by invading rats. These results have important implications for interpreting the relative roles of recolonization versus reinvasion following pest control operations. To properly manage invasive species at such sites, control must have the intensity of eradication efforts, and reinvasion must be managed both pre departure and post arrival.

    更新日期:2018-09-20
  • Kill, incarcerate, or liberate? Ethics and alternatives to orangutan rehabilitation
    Biol. Conserv. (IF 4.66) Pub Date : 2018-09-18
    Alexandra Palmer

    Despite its high cost and debatable conservation value, orangutan rehabilitation and reintroduction (R&R) continues. Drawing on qualitative research with orangutan conservationists, this paper argues that a central reason why R&R practitioners undertake this activity is a view that the alternatives, killing orangutan orphans or keeping them in captivity, are practically or ethically unacceptable. However, questions remain over whether orphans might be better off in captivity than in the wild, and why orphans appear to attract more attention and support than wild orangutans. In evaluating these questions, practitioners must weigh up obligations to individuals and larger units, displaced and wild orangutans (the former visible, and the latter abstract), and properties of orangutans such as their wildness, welfare, and autonomy. As advocates of compassionate conservation have highlighted, similar ethical dilemmas arise in the conservation of other species.

    更新日期:2018-09-18
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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