Harmful Algal Blooms (HABs), specifically red tide, can cause coastal economic activity to slow in Southwest Florida. Popular as a vacation destination, the area thrives on revenue generated by its beach access and proximity to fresh seafood. When blooms persist for multiple months in a row, fishery and seafood related businesses feel the negative effects. We examine taxable sales receipts for the

Shifting temporal or non-linear relationships between angler behavior and fish population characteristics can mask population declines or produce unexpected regulation outcomes. We tested for hyperstability in seasonal and interannual trends in angler effort, catch, and harvest rates in bluegill (Lepomis macrochirus), black crappie (Pomoxis nigromaculatus), and yellow perch (Perca flavescens) across

Small-scale fishery monitoring programs can provide valuable information about ex-vessel prices, which are essential for economic analyses and fisheries management. Ex-vessel prices obtained without adequate statistical support can generate inconsistent data and imprecise estimates that do not comply with quality standards that guarantee their usefulness in decision-making. We propose methodological

Shifts in size structure have been documented for many commercially exploited marine fish stocks, thought to be attributed to size-selective harvesting practices coupled with changing oceanic conditions. Northwest Atlantic monkfish (Lophius americanus) is a commercially valued species in the United States that is commonly caught as bycatch in Canadian scallop and groundfish fisheries. This uniquely

Sound is an environmental feature that is used by a variety of marine taxa for feeding, reproduction, navigation and predator avoidance. Consequently, alterations to the soundscape have the potential to alter an individual’s behaviour, physiology and ultimately fitness. Furthermore, such responses have the potential to negatively influence commercial fishing interests. In Atlantic Canada, snow crab

Choosing among recovery tactics for fish populations is challenged by high costs and uncertain outcomes. Depressed populations of salmonids are often supplemented using hatchery propagation; these strategies may involve releasing fish at different locations, densities, and life stages. We describe a unique decision context where supplementation is used to improve anadromous returns of a mixed anadromous-resident

Although the phenomenon of skipped spawning has been described in numerous fishes, time-series are scarce. We used the presence of post-ovulatory follicles in histological gonad slides from females not developing oocytes for Northeast Arctic (NEA) haddock Melanogrammus aeglefinus from 2009 to 2012 to construct a length-based statistical model giving the probability that a non - developing female was

Tawi-Tawi, Southern Philippines, which has over 300 islands and huge reef systems, is geographically located at the heart of the Coral Triangle, the global center of coral reef biodiversity. In this study, we conducted an inventory survey of market fishes in Tawi-Tawi from October 2015 to December 2018. We considered 11 major commercially important coral reef fishes, namely, surgeonfish (family Acanthuridae)

Small-scale fisheries account for most of the worldwide landings and employment. However, they are difficult to manage scientifically because the program of research and management applied to the relatively few large-scale fisheries is too onerous to be expanded to the myriad small-scale fisheries. Does this mean that SSF have a higher risk of overfishing so it would be necessary to implement more

The landing obligation in the revised European Union Common Fisheries Policy allows for exemptions to obligatory landing of the entire catch for species for which “high survival” of discards can be demonstrated. Nephrops norvegicus is an important target species in many fisheries across Europe in the Mediterranean Sea, NE Atlantic Ocean and North Sea. Historically, Mediterranean fisheries have had

This study explores trade-offs between fish quality, fishing efficiency, costs and profitability across three different vessel groups in the Norwegian groundfish fishery, that is, vessels fishing with bottom trawls, longlines and Danish seines. The results of hedonic price analysis at the ex-vessel level of the value chain indicate substantial differences in fish quality as Atlantic cod caught with

Demographic and environmental factors can influence the spatial distribution of fish populations, potentially affecting the timing, location, and magnitude of harvest. Quantifying these relationships can be complicated, if their effects vary spatially over a population’s range or are non-additive (i.e., interactive), where one factor mediates the effect of another. Toward understanding the relative

The giant ruby snapper, Etelis sp., attains the largest size of any lutjanid in the Indo-Pacific and is one of the most valuable species harvested from deep-water fisheries along the continental and insular shelf margins throughout its broad geographic distribution. Despite this species supporting important commercial, artisanal and subsistence fisheries, quantitative assessments of the status of stocks

Pelagic false killer whales (Pseudorca crassidens) are killed or seriously injured in the Hawai‘i-based deep-set longline fishery more than any other cetacean, with bycatch regularly exceeding allowable levels. Telemetry data from five satellite-tagged whales (from three groups) and longline logbook entries (4182 sets) from the Hawai‘i-based longline fisheries are used to assess the range of the population

The inclusion of unwanted targets in hydroacoustic surveys biases estimates of fish abundance. Thus, knowledge of frequency-dependent responses of unwanted targets (e.g., pelagic macroinvertebrates) can help ensure that transducer frequencies are used that minimize this bias. We determined how fish density estimates varied across multiple frequencies when the larval stage of a midge, Chaoborus, was

Portugal plays a major role in shark, skate and ray fisheries in the European Union. With the decline of these animals raising concerns amongst scientists all over the world, we set out to provide an updated assessment on elasmobranch landings in Portugal between 1986 and 2017. The dataset analysed in this study consisted of 15,521 records, each with information concerning the species (or higher taxonomic

The genus Chionodraco includes three morphologically similar species, two of them (C. hamatus and C. myersi) living sympatrically in the Eastern Antarctica, and the third one (C. rastrospinosus) being distributed in the Western Antarctica along the southern Scotia Arc. The few overlapping diagnostic characters are often useless for the right taxonomic identification of three species, complicated by

Horse mackerel, Trachurus trachurus, specimens sold in supermarket chains in the metropolitan area of València (Spain) were analyzed to assess which intrinsic and extrinsic factors are able to diminish the risk of human anisakiosis. 202 T. trachurus, caught in the Atlantic Ocean and the Mediterranean Sea, were examined for ascaridoid nematodes. The overall prevalence and abundance of Anisakis type

Vendace (Coregonus albula) is a small and rapidly reproducing planktivorous coregonid species that is known to endure very high fishing pressure. Catch levels of 10–25 kg ha−1 a−1 have been sustained for extended periods in several Finnish lakes without signs of fishery-related deterioration of recruitment or decline of spawning stocks. However, data from the lake Säkylän Pyhäjärvi (SW-Finland) in

Restocking of European eel (Anguilla anguilla) is a widespread practice throughout Europe. Conditions during restocking activities and mortality related to restocking practices have been discussed, however, factors affecting these restocked populations afterwards are mostly not considered. In this study we used a machine learning method followed by generalized linear model to analyze long time eel

The potentially negative effects of genetic drift are expected to be minor in in fisheries species because they are numerically abundant, fecund and able to move freely in ecosystems that lack barriers to gene flow. Here we investigate the operation of genetic drift in a fisheries species that has experienced a dramatic decrease in population size. On the east coast of Australia between 1977–1988 the

Great Lakes-wide population structure analyses using neutral markers have provided an understanding of broad-scale genetic structure of lake sturgeon. To assess the fine-scale genetic structure of lake sturgeon populations in two different rivers, we combined both microsatellites and genome-wide SNP markers. The St. Clair-Detroit River System (SCDRS) is entirely freshwater with no known impediments

Spatio-temporal models are increasingly used to develop indices of population abundance from fishery-dependent and –independent data. Developments in spatio-temporal index standardization were discussed at a workshop hosted by The Center for the Advancement of Population Assessment Methodology (CAPAM) titled “Development and application of spatio-temporal models to derive indices of relative abundance”

Floodplains comprise a complex mosaic of seasonally-flooded forests, lakes and channels that support productive fisheries. These habitats and their fish populations are increasingly threatened by a variety of human pressures, including floodplain deforestation. However, the effects of multiple human pressures on these floodplain fisheries have not been studied in the Amazon River. Here, we investigated

Migration routes of exploited marine resources are often investigated using tracking methods such as satellite tags or Data Storage Tags (DSTs). However, this type of research crucially depends on the tagging and recapture effort, and is often unfeasible for small migratory pelagic fish such as capelin because of size constraints. We investigated the spawning migration route of capelin along the shelf

We report results from the first detailed investigation of elasmobranch bycatch that contains data on species, sex, and length-frequency distributions of animals collected in the coastal south-eastern and entrance region of the Gulf of California. Using data from fishery-independent prawn trawl surveys between 2011–17, we found differences between years and zones in the number of species per tow in

Despite the Maori snapper, Lutjanus rivulatus, being a targeted fisheries species throughout its broad geographic distribution across the Indo-Pacific region, this is the first study of its age-based life history characteristics. Information on the age, growth and longevity of a species can improve our understanding of its inherent vulnerability to exploitation. In Western Australia (WA), this species

The European green crab (Carcinus maenas) continues to expand in Atlantic Canada and other coastal regions worldwide. Since most control measures for this species have failed, there is a need for innovative and ecologically responsible mitigation measures. One such measure is a green crab control harvesting wherein affected fishers could recoup some of their losses through value-added products. As

Blue catfish, Ictalurus furcatus, are an invasive species in the Chesapeake Bay region, where they negatively impact native species of ecological, economic and cultural value. Management of blue catfish is, however, hindered by a lack of information on their population dynamics. We studied decadal changes in growth and body condition and made inferences about maturity schedules of blue catfish in two

Improvements in electronic tag technology have enhanced the ability to monitor the post-release fate of fish and estimate discard mortality rates (DM) under real-world conditions. However, correctly estimating DM requires disentangling the influence of capture-related mortality from natural (background) mortality (M), particularly when M rates are elevated. To accomplish this, many published studies

Lake Victoria biophysical and geochemical status has changed dramatically within an unprecedentedly short time scale driven by human actions. These actions can be broadly classified as escalated fisheries exploitation, biomanipulation (characterized by species introduction) and catchment processes. A chronology of these activities since 1901 to present times is described and, where possible, related

Reference points are central in the current management of marine living resources. However, reference points are estimated from data and model estimates. Therefore, they are inherently uncertain. We present two objective methods for estimating reference points and quantifying their uncertainty. The first method uses per-recruit calculations, while the second method relies on a long-term forecast of

A total of 120 Caspian Sea trout specimens from five streams and Lar Lake of the Lar National Park plus 27 Caspian Sea trout specimens (out-group) from the Babolrud River drainage in the Caspian Sea Basin (Iran) were analyzed using 12 microsatellite loci to assess population genetic structure and to estimate the contribution of each population to the lake-run stock. In addition to the Babolrud River

The Schaefer and Pella-Tomlinson production models (LPM and PTPM) can be used to provide management advice in data poor situations, as they require only a time-series of catches and an index of abundance. These models are commonly fit using Bayesian methods, with the prior for the intrinsic rate of growth (r) set based on the results of a demographic analysis. We used simulations based on blue shark

Outliers caused by atypical observation error often occur in fishery data. These outliers have an adverse effect on the parameter estimation for fishery stock assessment models. We tested a robust distribution for identifying and removing outliers from fishery data. We conducted a simulation study in which a surplus production model was used to mimic fishery population dynamics and outliers caused

Metal:Ca ratios (Li:Ca, Cu:Ca, Fe:Ca, Na:Ca, Rb:Ca, Pb:Ca and Zn:Ca) in fin spines of Genidens barbus, an endangered catfish species, were used as possible habitat markers from three Southwestern Atlantic sampling areas (Paranaguá estuarine complex, Brazil; Paraná River Delta, Argentina-Uruguay; and Negro River, Patagonia). Significant differences (p < 0.05) among sites for metal:Ca ratios support

Tropical and subtropical shrimp fisheries occur mainly nearshore, where numerous non-target species (bycatch) are captured. Bycatch is a serious issue for fishing activity and understanding its impacts through integrative analyses of the bycatch structure is necessary. In Brazil, information on bycatch composition and structure is limited. As such, we conducted a study on the target species and bycatch

The Atlantic mackerel, Scomber scombrus, is an economically important and widely distributed fish species in the North Atlantic, currently considered to comprise two stocks: the North-West Atlantic (NWA) and the North-East Atlantic (NEA). Each stock is composed of different spawning components which involve temporal and spatial movements driven by the environment. Thus, resolving the species population

The Hawaii-based longline fishery targeting bigeye tuna and swordfish is the most economically important fishery in Hawaii. An improved understanding of the distribution of swordfish within this fishery and how it changes in response to environmental conditions is critical for predicting potential climate change impacts to the fishery. The multi-species Vector-Autoregressive Spatio-Temporal (VAST)

The establishment of non-native, habitat-forming seaweeds into new areas may trigger changes in ecosystem functioning, including the spatial redistribution of native biodiversity. These changes can in turn affect socio-economic systems. We studied the question whether the spatial behaviour of marine anglers is altered by the presence of a non-native seaweed using a novel image-based method to measure

Delineating the stock structure of highly-mobile, wide-ranging fishes subject to exploitation is a challenging task, yet one that is fundamental to optimal fisheries management. A case in point are stocks of skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus) and albacore tuna (Thunnus alalunga) in the Pacific Ocean, which support important commercial

Understanding movement patterns of fish provides a context for making sound management decisions related to these populations; archival tags can provide this information. To better understand the depth-specific behavior of Greenland turbot Reinhardtius hippoglossoides in the Bering Sea and Aleutian Islands region, 297 temperature and depth recorders (archival tags) were implanted in fish between 2003

This paper considers a general state-space stock assessment modeling framework that integrates a population model for a fish stock and a data model. This way observed data are linked to unobserved quantities in the population model. Using this framework, we suggest two modifications to improve accuracy in results obtained from the stock assessment model SAM and similar models. The first suggestion

In this study, the taxonomic resolution and phylogenetic relationship of two presumed subspecies of Merlangius merlangus, namely M. m. euxinus and M. m. merlangus, were investigated. In addition, the effect of the Turkish Straits System on the evolutionary history and genetic structure of M. merlangus, was explored. The mitochondrial cytochrome c oxidase subunit 1 and cytochrome b genes, and the nuclear

Minimum landing sizes (MLS) are commonly used to manage crustaceans and are generally set above the size at first maturity to ensure that some protection is afforded to exploited stocks. Despite the economic importance of the brown crab fishery in Scotland, the species is considered data-poor and only limited information is available on size-at-maturity. This study provides, for the first time, estimates

Statistical habitat models, such as spatial generalized linear mixed models (GLMMs) and spatial generalized additive models (GAMs), provide valuable products to habitat assessments and ecosystem-based fisheries management (EBFM) efforts. In particular, derived spatial distribution maps and quantitative relationships of marine organisms to environmental variables (e.g., suitability indices) can be employed

Tunas are the focus of significant fisheries in the Pacific Ocean, where landings of four species – skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus) and albacore tuna (Thunnus alalunga) – constitute approximately 70 % of the global tuna catch. Stock assessments for skipjack, yellowfin and bigeye tunas in the Pacific Ocean currently assume eastern

A prerequisite in fisheries management is to identify biological meaningful delineations of stocks, the fundamental exploited units. The European anchovy is one such species in need to better identify stock boundaries. Indeed, despite a spawning aggregation behaviour both in the southern Bay of Biscay and southern North Sea in spring and summer, it has a seemingly continuous distribution in autumn

Integrated analysis (or integrated population modelling) methods have become the preferred approach for conducting stock assessments, and providing the basis for management advice for fish and invertebrate stocks since the publication of a seminal paper by Fournier and Archibald in 1982. Methods to assess fish stocks based on single-species, single-area, age-structured models are now standard, with

All fish populations and fisheries exhibit spatial structure, but accounting for the spatial patterns is commonly ignored in most stock assessments. The Center for the Advancement of Population Assessment Methodology (CAPAM) hosted a workshop on “Spatial Stock Assessment Models” (La Jolla, CA, USA; October 1-5, 2018), and this special volume includes twelve papers on various aspects of spatial stock

The need to produce sufficient food for people whilst also maintaining biodiversity and ecosystem integrity is one of the most pressing challenges in the 21st century. This challenge is exemplified in wetlands and deltas of Southeast Asia that have been transformed to intensify rice production and have subsequently lost the naturally present wild aquatic species that previously bolstered local food

The red scorpionfish Scorpaena scrofa (Linnaeus 1758) is a species of high commercial value in the Western Mediterranean Sea. The market value of S. scrofa is highly related to its size, with smaller individuals, less than 25 cm, sold mixed with other species with a low commercial value with respect to the larger ones. Fishing stress and survival of the specimens of S. scrofa under 25 cm were analysed

Fisherman have known and explored the association between tuna and whale sharks for centuries. Just as in the past, present day industrial fishers search for the presence of whale shark as cue to locate tuna schools. These whale shark-tuna associations have been usually assumed to result from the same ecological drivers that govern the attraction of tunas and other fishes towards floating objects or

Inland fisheries can support complex social-ecological systems and contribute to food security. However, many target stocks lack monitoring and quantitative assessment. There may be scope to apply current data-limited assessment models in these fisheries. The Length-Based Spawning Potential Ratio (LB-SPR) model requires only fish length data and input estimates of key life history parameters. LB-SPR

We describe and illustrate a spatio-temporal modelling approach for analyzing age- or size-specific catch-per-unit-effort (CPUE) data to develop indices of relative abundance and associated composition data. The approach is based on three concepts: 1) composition data that are used to determine the component of the population represented by the index should be weighted by CPUE (abundance) while the

Indonesia is the most important producer country of snapper and grouper species worldwide, with a notable increase in landings over the past decades. The Java Sea is one of the most frequently fished areas for these species in Indonesia, but in 2016 a decrease in landings was observed. This study applied two approaches (Length-based Indicators and Length-Structured Growth-Type-Group Model) to assess