Contaminants of emerging concern (CECs) are prevalent in aquatic landscapes and may be a factor in population declines of aquatic and terrestrial fauna. Yet, there are limited data to assess the impacts of CECs to species. Understanding CEC impacts is particularly important for imperiled freshwater mussels which provide valuable ecosystem services. CEC exposure of freshwater mussels was characterized

A deep chlorophyll layer (DCL) is a common feature of many deep, oligotrophic lakes including Lake Superior. Mechanisms generating and maintaining DCLs are variable across lakes, and seasonal patterns and relationships of DCL structure to physical variables are not well described. Using vertical profile data for physical and biological variables from western and central Lake Superior, we described

Despite sustained attention to water resource issues in the Great Lakes and around the world, many water problems remain unresolved because their sources or causes are external to the water sector. Water governance often is based on water-centric problem framings that do not take sufficient account of the role of external actors, institutions, and drivers. Recognition of this problem is growing, but

Crocodiles play important roles in many ecosystems, but their populations worldwide are threatened by human exploitation and habitat destruction. We studied ontogenetic changes in habitat use and seasonal activity patterns in a population of Nile crocodiles (Crocodylus niloticus) inhabiting the Lake Albert Delta Wetland System, a Ramsar Site of international importance in Murchison Falls National Park

The set of ancient lakes on Sulawesi, Indonesia, represents a unique global hotspot of aquatic biodiversity. These lakes have been recognized widely because of their high number of endemic species with specialized and distinctive morphological characters, life history and ecological adaptations. An interesting case of unusual life history involving brood care exists in the planorbid limpets of the

We investigated the hypothesis that ostracode populations are sensitive to variations in sediment discharge related to watershed differences at Lake Tanganyika. Many ostracode species are documented to be sensitive to high turbidity which increases during runoff from strong rainfall events and changes in ostracode populations can impact organisms higher in the food web. We compared surficial death

Spatiotemporal relationships between developmental stages (cydippid, transition and adult) of the comb jelly Mnemiopsis leidyi and environmental parameters were seasonally evaluated using the random forest (RF) model along the Iranian coasts of the Caspian Sea. The mean density of M. leidyi in spring, summer, autumn and winter were 8, 54, 130, and 15 ind m−3, respectively. The density of various stages

The tubenose goby (Proterorhinus semilunaris) entered the Great Lakes in the 1990s via ballast water, but remains poorly studied within North America, making it difficult to predict its effects on native ecosystems. Dietary breadth and somatic growth rate have important ramifications for survival, competitiveness, and dispersal ability of a fish species, and thereby its ecological impact. We studied

With the exception of lake whitefish (Coregonus clupeaformis), relatively little is known about the early life history of larval coregonines in the Laurentian Great Lakes. For example, our knowledge of the feeding ecology of larval coregonines (excluding lake whitefish) is based on only 900 stomachs reported in the literature. Here, we describe the diets and demographics of larval coregonines from

Underwater video is increasingly used to study aspects of the Great Lakes benthos including the abundance of round goby and dreissenid mussels. The introduction of these species has resulted in major ecological shifts in the Great Lakes, but the abundance and impacts of these species have heretofore been underassessed due to limitations of monitoring methods. Underwater video (UVID) can “sample” hard

Limnothrissa miodon is a small pelagic clupeid that was introduced into Lake Kivu in the late 1950s to fill an empty niche. Since then, it has become the main fishery in the lake. The fish stocks were estimated by hydroacoustics between 2012 and 2018 to provide information on the fishery in the current context of changing environmental factors. The main objectives were to determine the most appropriate

Eutrophication has been linked to increased greenhouse gas emissions from inland waters. Phytoplankton blooms in Lake Erie have increased since the 1990s, although its greenhouse gas emissions are not well characterized. We measured CH4 and N2O concentrations and diffusive fluxes in four seasons around the entire lake, and CO2 fluxes in one summer season. Lake Erie is a source of CH4 all year across

Tributaries provide spawning habitat for three of four major sub-stocks of Lake Erie walleye (Sander vitreus). Despite anthropogenic degradation and the extirpation of other potamodromous species, the Maumee River, Ohio, USA continues to support one of the largest fish migrations in the Laurentian Great Lakes. To determine if spawning habitat availability and quality could limit production of Maumee

A successful management plan requires clear goals and a process for evaluation. Without them, managers risk operational shifts in which continuous changes disguised as improvements may have little beneficial effect. The conception, design, and operation of an electric barrier and fishway on the Pere Marquette River of Lake Michigan serve as an illustration. The Great Lakes Fishery Commission operated

Four of the Great Lakes and Lake St. Clair serve as part of the 5261 km coastline of the State of Michigan. Understanding of the relationship between Michigan residents and these Lakes are important for the creation of messages designed to instill the desire to become better stewards of the Michigan coastline. Focus groups totaling 100 Michigan residents were held across the State to learn how residents

In large and shallow lakes, the role of the redox-related release of phosphorus (P) from sediments has remained in the shadow of sediment resuspension. In the current study, we concentrated on this knowledge gap regarding factors controlling lake water quality. We combined long-term monitoring data with the studies on sediment P mobility in August 2018 by measuring redox potential, pore water concentrations

Identification of sources of fecal pollution in urban areas is critical for protecting public health, the environment, and guiding remediation. We collected 670 water samples at 46 sites in 2018 to study fecal pollution in the Toronto Harbour and Don River watershed. Water samples were analyzed for E. coli, wastewater chemicals, and microbial source tracking DNA markers using a digital PCR technique

Lake Michigan salmon and trout populations are important species for recreational fisheries and food web management, and are largely supported through stocking efforts, with varying degrees of natural recruitment. Ongoing fisheries management of these salmonine populations is dictated by relationships between predator and prey abundance as well as community structure within the lake. However, while

High-resolution lake ice/water observations retrieved from satellite imagery through efficient, automated methods can provide critical information to lake ice forecasting systems. Synthetic aperture radar (SAR) data is well-suited to this purpose due to its high spatial resolution (approximately 50 m). With recent increases in the volume of SAR data available, the development of automated retrieval

Ten anadromous lamprey species (Petromyzontiformes) are recognized around the world, including four species in the Southern Hemisphere and six in the Northern Hemisphere. Eleven threats to these anadromous lampreys have been identified: climate change, shifting oceanographic regimes, artificial barriers, low water quantity/flow management, habitat degradation, poor water quality, reduced habitat availability

Freshwater drum (Aplodinotus grunniens) may be a predator of the invasive zebra mussel (Dreissena polymorpha), which established in Lake Winnipeg in 2013. In this study, the diets, trophic position, and growth of 51 freshwater drum collected in 2019 (six years post-zebra mussel invasion) were compared to 64 freshwater drum sampled in 2000. Benthic insect larvae were the dominant food items in both

The contribution of septic systems to watershed nutrient loads is poorly quantified although septic systems are often cited as potentially important nutrient sources. The study uses a geospatial model to estimate phosphorus loads from septic systems to the tributaries of the Canadian Lake Erie Basin to inform Lake Erie nutrient management initiatives. There is currently no inventory of septic systems

During the period February to June 2020, heavy rainfall caused increases in levels and flooding in many lakes in East Africa. This coincided with the COVID-19 pandemic. These calamities affected ecosystems and livelihoods, especially of fishers who depend on fisheries as their only source of livelihood. This study examined the effects of COVID-19 and flooding on the major inland capture fisheries in

Sea lamprey (Petromyzon marinus) is a species of conservation concern in their native range of the Atlantic coasts of Europe (Near Threatened to Critically Endangered) and North America (Secure to Critically Imperiled), and an invasive species of great economic and ecological concern in the Laurentian Great Lakes. Despite differences in life history strategy (anadromous natives vs adfluvial non-natives)

While nutrient loading has affected all levels of Lake Winnipeg’s ecology, its greatest influence has likely been on the microbial community. In addition to eutrophication, zebra mussels (Dreissena polymorpha) have recently invaded the ecosystem and threaten food web dynamics. Their filter-feeding predation and association with bacteria, specifically phototrophs, was investigated. A sampling trip to

A time-series (1990–2013) of classified vegetation cover maps was produced for Netley-Libau Marsh, a 26,000 ha coastal wetland on Lake Winnipeg, to assess its current status and verify earlier trends of emergent vegetation loss. Open water area in the marsh was measured from late-summer Landsat images for 20 years; three classes of vegetation types (emergents, wet meadows, upland) could also be identified

In freshwater aquatic ecosystems, submerged aquatic vegetation (SAV) is critical habitat for may fish species and provides a variety of ecosystem services including nutrient filtration and substrate stabilization. Characterizing habitats and assessing their suitability for fish and other aquatic and terrestrial organisms is an important component of delisting efforts in the Toronto and Region Area

Hydroacoustic surveys using hull-mounted down-looking transducers are useful for estimating pelagic fish densities; however, this method may miss shallow fish owing to the acoustic surface dead zone and vessel avoidance. Our objective was to compare pelagic fish density estimates acquired by a traditional down-looking acoustic survey to estimates obtained by a new multi-directional-towed sled capable

Lake changes have great impacts on local and regional ecosystems and socioeconomic activities. To determine the recent changes in Hongze Lake, radar altimeter and Landsat data were used to examine the water level and area and estimate the water volume changes from 2003 to 2018. Generally, the annual water level results from radar altimeter data showed good agreement with in situ measurements (r2 = 0

Lake trout (Salvelinus namaycush) are an ecologically and economically important piscivore with reported differences in diet and feeding behaviour throughout its range. Eleven stomach content and stable isotope-based metrics were used to describe diets of 349 lake trout between two years (2013 and 2018) and among geographic zones (west, central, east, Kingston basin) in Lake Ontario. Using individual

Environmental contamination is of global concern. Lamprey are scientifically, ecologically, culturally, and economically important fishes. Our study represents the first synthesis ever on environmental contamination in lamprey. Objectives of this study include: (1) evaluate lethal and sublethal effects of environmental contaminants on lamprey, thereby providing insight into the potential for environmental

Effects of lake level fluctuations on coastal bluff erosion in the Great Lakes are pervasive and of significant concern to policy-makers and property owners. Previous studies of bluff erosion have primarily estimated two-dimensional bluff recession rates over years to decades. However, bluff erosion is an irregular process in time and space so averaging coarse resolution observations over long time

Animal populations are assessed to estimate rates of artificial and natural mortality at ecologically relevant spatial and temporal scales to develop exploitation quotas. But how the population’s natural mortality rate and how the ability to observe the population changes through time are poorly understood in most invasive fishes, despite efforts to control their populations. By investigating a 30-year

It is well documented that fish consumption imparts both health risks and benefits. Furthermore, fish harvest and consumption are an essential part of Great Lakes Native American cultures. Quantitative models that compare risk and benefits to potential consumption scenarios can help guide future health research as well as consumption advice for potentially sensitive populations. This article presents

There is concern of economic and environmental damage occuring if any of the four major aquacultured carp species of China, black carp Mylopharyngodon piceus, bighead carp Hypophthalmichthys nobilis, silver carp H. molitrix, or grass carp Ctenopharyngodon idella, were to establish in the Laurentian Great Lakes. All four are reproducing in the Mississippi River Basin. We review the status of these fishes

Sea lamprey control in the Laurentian Great Lakes relies on records of sea lamprey wounds on lake trout to assess whether control efforts are supporting fisheries management targets. Wounding records have been maintained for 70 years under the assumption that they are a reliable and accurate reflection of sea lamprey damage inflicted on fish populations. However, two key assumptions underpinning the

Erosion and accretion of various magnitudes occur along the southwest Lake Michigan shoreline. These processes are triggered by natural events and human activities, which affect the distribution and thickness of sand on the nearshore lake bottom. Significant erosion along the Illinois coastline has highlighted the need for a large-scale means of acquiring spatially rich data to build models of sand

Microplastic particles, often studied as aquatic pollutants, have been recovered from coastal dunes along the shores of Lake Ontario and Lake Erie in New York and Pennsylvania. Surface and shallow sub-surface sand samples were collected from coastal dunes in 1 m2 areas from 5 locations along Lake Erie: Sunset Bay, Dunkirk Harbor, Point Gratiot, and Canadaway Creek in New York and Presque Isle State

Lake Winnipeg has undergone rapid eutrophication over the last several decades with a large portion of the associated nutrient loads delivered via the Red River. Consequently, subcatchments of the Red River Valley (RRV) are priorities for nutrient management, an aim that requires identification of key nutrient sources to stream food webs. We identified the primary sources of nitrogen to food webs of

Prior research suggested using double-crested cormorants (Phalacrocorax auritus) as an indicator species to track anthropogenic debris in inland aquatic environments such as the Great Lakes. In this study, we sampled cormorant nests on the ground (n = 50) for the presence and type of debris at the Leslie Street Spit, a human built peninsula in Toronto, Ontario. We also compared the proportion of debris

The Great Lakes are influenced by established aquatic invasive species (AIS) and the threat of new invaders persists. Grass carp, one of four species commonly referred to as Asian carp, are considered invasive because of their ability to adversely modify aquatic habitat through consumption of aquatic macrophytes. Grass carp have been infrequently detected in the Great Lakes since the mid-1980s. More

Over the last several decades, multiple environmental issues have led to dramatic changes in the water clarity of the Great Lakes. While many of the key factors are well-known and have direct anthropogenic origins, climatic variability and change can also impact water clarity at various temporal scales, but their influence is less often studied. Building upon a recent examination of the univariate

Asian carps are threatening to establish in the Great Lakes basin and the examination of factors leading to spawning success is vital for preventive efforts. Hydrodynamic modelling can determine if successful hatching of carp eggs can occur in a tributary, by predicting egg movement during a spawning event to see if hatching can occur before eggs settle. A 3-D hydrodynamic model, coupled with a Lagrangian

Relative contributions of aquaculture-origin and naturally-reproduced grass carp (Ctenopharyngodon idella) in the Laurentian Great Lakes have been unknown. We assessed occurrence and distribution of aquaculture-origin and wild grass carp in the Great Lakes using ploidy and otolith stable oxygen isotope (δ18O) data. We inferred natal river and dispersal from natal location for wild grass carp using

Understanding the relationship between a species and its habitats is important for both conservation of imperiled species and control of invasive species. For migratory species, we hypothesize that maintaining connectivity between segregated habitats is more important than improving the quality of each habitat. In the case of anadromous lampreys of conservation concern, we posit that restoring passage

Since the identification of 3-trifluoromethyl-4-nitrophenol as a lampricide in the 1950s, control of sea lamprey populations in the Great Lakes has largely relied on lampricides, barriers, and traps. Lampricide treatments target larval lampreys in tributaries of the Great Lakes. The Great Lakes Fishery Commission oversees sea lamprey control efforts and has invested in technologies that may target

The St. Marys River connects Lake Superior to Lake Huron, comprising the international border between Michigan, United States, and Ontario, Canada. This Great Lakes connecting channel naturally encompasses various habitats including lakes, wetlands, islands, tributaries, side channels, and main channels. The St. Marys River Rapids are shallow rock areas with high flow velocities (>1 m/s) in the upper

Three different types of microplastics (MPs): low density polyethylene; polypropylene; and polyester, were incubated for one and three months at two sites (Channel and Lake) in Muskegon Lake (MI). After retrieval, MPs were analyzed for polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs), select metals, and genomic characterization of the attached microbial

We tested the hypothesis that the analysis of operationally defined sedimentary phosphorus species gives a finer resolution of historical land-use changes in lake watersheds than does total phosphorus alone. We measured loosely sorbed/interstitial, reductant soluble, aluminum-bound, apatite, organic and total phosphorus in eleven cores taken from heterogeneous regions of Lake Champlain using sequential

Over a century ago, shoreline copper mills sluiced more than 64 million metric tonnes of tailings into Lake Superior, creating a “halo” around the Keweenaw Peninsula with a buried copper peak. Here we examine how tailings from one of the smaller mills (Mass Mill, 1902–1919) spread as a dual pulse across southern Keweenaw Bay and onto tribal L’Anse Indian Reservation lands. The fine (“slime clay”) fraction

Thiamine (vitamin B1) deficiency in Great Lakes salmonines has been linked to consumption of alewife Alosa pseudoharengus. Thiamine deficiency has been recognized as a possible impediment to lake trout Salvelinus namaycush recruitment in the Great Lakes and Atlantic salmon Salmo salar recruitment in the Finger Lakes and Baltic Sea. Alewife invaded Lake Champlain in 2003 which provided an opportunity

Spawning of grass carp, Ctenopharyngodon idella, in the Great Lakes basin was verified when eight fertilized eggs were collected in the Sandusky River, a tributary to Lake Erie, in 2015. Using a fluvial drift model (FluEgg) and simulation modeling, researchers predicted the fertilization location for those eggs was 3.8 ± 1 km (95% credible interval, CI) downstream of Ballville Dam. In June 2018, simultaneous

Lampreys (Petromyzontiformes) are a key component of freshwater ecosystems throughout temperate parts of the world. Of the 44 described species of lamprey, the sea lamprey (Petromyzon marinus) is certainly the most commonly recognized. This species has expanded its range from the Atlantic Ocean basin where it is of conservation concern in North America and Europe into the Laurentian Great Lakes where

Lampreys worldwide face multiple anthropogenic stressors. Several species are ‘at-risk’ listed, yet abundance data for most remain insufficient to adequately assess conservation status. Lamprey population declines are largely due to habitat degradation and fragmentation, pollution, and exploitation. Conservation priorities include: quantification of population trends and distribution; identification

Managers and researchers have identified a reproducing population of grass carp (Ctenopharyngodon idella) in the western basin of Lake Erie, generating concern over the potential threat to ecosystem function in the Great Lakes Basin. Capture histories indicate that grass carp may be present at low levels in other areas of Lake Erie, necessitating a large scale, multi-jurisdictional response. As a result

Barriers and pesticides have been used in streams to control sea lamprey in the Laurentian Great Lakes for nearly 70 years. Considerable effort has been spent to develop additional control measures, but much less effort has gone toward identifying how or where additional control measures might be cost-effectively integrated into the sea lamprey control program. We use a management strategy evaluation

Lake sturgeon, a species of conservation concern, can be affected by sea lamprey control activities in the Great Lakes basin. Specifically, age-0 lake sturgeon are sensitive to the pesticides used to kill larval stage sea lampreys; and, as tributary spawners, barriers that restrict access to habitat for adult sea lampreys can also restrict access to spawning lake sturgeon habitat. Conversely, lake