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At least 1,459 records · Page 81Linked to original sources
USGS2026

Bottom trawl assessment of Lake Ontario’s benthic prey fish community, 2025

Since 1978, bottom trawl surveys in Lake Ontario have provided information on the status and trends of the benthic prey fish community related to Fish Community Objectives that include understanding prey fish population dynamics and community diversity. Beginning in 2015, the benthic prey fish survey expanded from only U.S. sites to incorporate Canadian sites, increasing the survey’s spatial coverage to a lake-wide scale. Additionally, sampling in the eastern U.S. embayments (Black River, Chaumont, Guffin, and Henderson Bays), that were historically sampled during a September bottom trawl survey to index Yellow Perch ( Perca flavescens ; 1978-2007), resumed in 2015. The current survey provides abundance indices for sculpins, Round Goby ( Neogobius melanostomus ) and Bloater ( Coregonus hoy i) using techniques, gear, and timing comparable to surveys on Lake Michigan. This alignment provides a necessary biological reference point for evaluating Lake Ontario Bloater reintroduction. In 2025, the benthic prey fish survey completed 100 bottom trawl sites across main lake and embayment habitats at depths from 6 to 168 m. Sampling in US waters was limited in 2025 compared to previous years. In total, the 2025 survey sampled 59,870 fish from 23 species. No Bloater were detected in the 2025 survey. Round Goby was the most common species comprising 46% of the total catch by number, followed by Deepwater Sculpin ( Myoxocephalus thompsonii ), White Perch ( Morone americana ), and Alewife ( Alosa pseudoharengus ) at 23%, 9%, and 9% respectively. Slimy Sculpin ( Cottus cognatus ) lake-wide biomass density continues to be lower than when lakewide sampling began in 2015; zero Slimy Sculpin were detected in US waters, however sampling in the main lake within US waters was limited to the southeastern area of Lake Ontario. Deepwater Sculpin biomass has remained high since population recovery began in 2010. Embayment sampling in 2025 was limited to only Chaumont Bay.

Lake Ontario↗
USGS2026

Inland habitat selection model for wintering whooping cranes

Inland habitat use by wintering Aransas-Wood Buffalo whooping cranes ( Grus americana ) is expected to increase given projected population growth and observations of some whooping cranes using inland winter habitat in addition to coastal marshes. We developed resource utilization functions using ‘random forests’ to model whooping crane use as a function of environmental covariates considered important for whooping crane use. Covariates associated with distance to cropland, distance to development, and wetness or standing water were the most influential in model prediction. The model estimated that the 50% predicted use contour encompassed 34,925 hectares (ha) and the 95% predicted use contour encompassed 328,928 ha within the study area. While presently limited by the small sample size of inland wintering areas observations ( n = 7 cranes with ≥50 locations), this model provides an initial tool for identifying potential impacts to whooping crane inland habitat use in proximity to anthropogenic development. The model can be expanded to incorporate future data to reduce uncertainty.

Texas↗
USGS2026

Stopover population estimate and migration ecology of Red Knots C. c. rufa at Delaware Bay, USA, 2025

Red Knots( Calidris canutus rufa ) rely on Atlantic horseshoe crab ( Limulus polyphemus ) eggs in the Delaware Bay to refuel during northward migration. Intensive harvest of horseshoe crabs in the 1990s contributed to declines in Red Knot numbers. In 2013, the Atlantic States Marine Fisheries Commission adopted an Adaptive Resource Management (ARM) framework to balance sustainable horseshoe crab harvest with ecosystem integrity and Red Knot recovery, requiring annual stopover population estimates. We estimated the 2025 passage population of Red Knots at Delaware Bay using a Bayesian analysis of a Jolly–Seber mark–resight model which accounts for population turnover and imperfect detection. We also evaluated change in migration timing between 2011 and 2025 with model-derived estimates of arrival at the Delaware Bay each year. The 2025 passage population was 54,043 individuals (95% credible interval: 47,926–61,928), an increase of approximately 17% over 2024 and only the second year since 2011 to exceed 50,000 individuals. Despite the increase, overlapping credible intervals across years indicate a stable stopover population. Migration timing has remained consistent, with 50% of the population typically arriving by 18 May and no evidence of advancement since 2011. These findings provide meaningful input for the ARMframework, supporting sustainable harvest of horseshoe crabs while maintaining adequate foraging opportunities for Red Knots and other shorebirds.

Delaware, New Jersey↗
USGS2026

Los Planes watershed vegetation monitoring: Standard operating procedures

This is a description of survey procedures for short term vegetation monitoring at Natural Infrastructure in Dryland Stream (NIDS) structure sites and control sites a ranch in the Los Planes, La Paz, Baja California Sur. This study design was modified from USGS Short Term Vegetation Response Study (Wilson et al. 2021) with the goal to quantify changes in species abundance/cover, structure, and composition. The Society of Ecological Restoration identifies 3 major ecosystem attributes of importance when assessing restoration projects, such as the installation of NIDS (Society for Ecological Restoration International Science & Policy Working Group 2004; Ruiz-Jaen and Mitchell Aide 2005). These attributes are vegetation structure, diversity, and ecological processes. Our protocol can be used to directly quantify vegetation structure and diversity and by collecting data over several years we can indirectly assess the ecohydrological processes associated with NIDS (Norman, Lal, et al. 2022).

Baja California Sur↗
USGS2026

Geologic map of the Sierra Nevada, California and western Nevada

THE GEOLOGIC MAP OF THE SIERRA NEVADA is a core component of the Sierra Nevada Earth Science Atlas, which also includes geophysical, neotectonic, economic, and geochronologic data. The map illustrates the distribution of geologic units across the Sierra Nevada and related adjacent areas. Geologic units are grouped by type and age into three categories: Principally Paleozoic and Mesozoic metasedimentary and metavolcanic wall rocks, most of which are grouped into terranes; Paleozoic and Mesozoic plutons and intrusive suites, which intrude the wall rocks and form the core batholith of the range; and Late Cretaceous and Cenozoic sedimentary and volcanic rocks and surficial deposits that unconformably overlap the older units. Related rock units were combined and simplified for presentation at a scale of 1:400,000, as shown in the list of map units and associated correlation of map units (Plate 1B) and description of map units (Appendix A). Tectonic faulting, folding and uplift have overprinted the rocks and have strongly influenced the spatial distribution of units and the distinct morphology of the Sierra Nevada as we see it today. The Atlas is the result of collaborative work by scientists and mapmakers from the California Geological Survey and the U.S. Geological Survey. The Atlas was originally envisioned by the late geologist Warren Nokleberg (1939-2021), who contributed much to the initial geologic map compilation

California, Nevada↗
USGS2026

Lake Ontario August gillnet survey and lake trout assessment, 2025

Lake Ontario Lake Trout ( Salvelinus namaycush ) rehabilitation has been assessed with fishery dependent and independent surveys to evaluate program benchmarks and compare observations with management objectives since 1983. These surveys provide information on the abundance, strain composition, and performance of stocked Lake Trout, as well as information on levels of natural recruitment, and Sea Lamprey ( Petromyzon marinus ) wounding rates. Lake Trout catch per unit effort (CPUE) in the August gillnet survey was notably lower in 2025. Percentage of naturally produced Lake Trout in US waters continued to be relatively low for mature and immature fish. Sea Lamprey wounding rates on Lake Trout > 432 mm in 2025 were below management target in US waters with zero A1 wounds observed. Overall, the 2025 survey results suggest that Lake Trout indicators continue to meet some of the management objectives but are not showing signs of meaningful recruitment to the adult stock.

Lake Ontario↗
USGS2026

Informing policy response to declining water supply in the Colorado River basin: Linking water supply management with outcomes for fish communities

Water-supply managers in the Colorado River Basin are tasked with balancing consumptive water use with natural water supply. Decisions associated with water-supply policy can include where and how much water consumption occurs, where water could be stored, and how to operate reservoirs. Water-supply decisions often affect other resources including energy production, recreation and aquatic ecosystems. The goal of this project was to model how different water supply management scenarios might affect riverine ecosystems with a specific focus on potential impacts on federally listed fish populations, including threatened humpback chub (Gila cypha) and endangered Colorado pikeminnow (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus). Threats to these endemic species include introduced non-native fish species that often become invasive, like smallmouth bass (Micropterus dolomieu), and altered physical conditions that may favor these non-native fish species over the endemic fish species. Changes in how water supply may be managed in the Colorado River Basin can affect physical conditions in rivers by altering how much water flows through a particular river segment at a given time, by changing the extent of riverine ecosystems between reservoirs, and by determining the quality of water released from storage reservoirs with fixed release elevation (e.g., full reservoirs generally release colder water). To address our goal, we developed tools that coupled water storage models, river temperature models and fish population models to examine how different scenarios to operate Lake Mead, Lake Powell, and Flaming Gorge Reservoir, the three largest reservoirs in the watershed, may affect fish populations. We developed our work plan when available water supply was diminished. At the end of our project period (May 2022), Lake Powell and Lake Mead contained historically low water levels, and our models were being used in evaluating different options for operating Lake Powell by the Bureau of Reclamation and other stakeholders.

Arizona, Utah, Wyoming↗
USGS2026

Status and trends of pelagic and benthic prey fish populations in Lake Michigan, 2025

Fall bottom trawl (fall BT) and lakewide acoustic (AC) surveys are conducted annually to generate indices of pelagic and benthic prey fish densities in Lake Michigan. The fall BT survey has been conducted each fall since 1973 using 12-m trawls at depths ranging from 9 to 110 m at fixed locations distributed across seven transects; this survey estimates densities of seven prey fish species [i.e., Alewife ( Alosa pseudoharengus ), Bloater ( Coregonus hoyi ), Rainbow Smelt ( Osmerus mordax ), Deepwater Sculpin ( Myoxocephalus thompsonii ), Slimy Sculpin ( Cottus cognatus ), Round Goby ( Neogobius melanostomus ), Ninespine Stickleback ( Pungitius pungitius )]. The AC survey has been conducted each late summer/early fall since 2004 (except 2020). The 2025 AC survey consisted of 26 transects [470 km total (292 miles)] covering bottom depths ranging from 5 to 259 m and 44 midwater trawl tows at 1.4 to 82.4 m fishing depth; this survey estimates densities of three prey fish species (i.e., Alewife, Bloater, and Rainbow Smelt). The data generated from these surveys are used to estimate various population parameters that are, in turn, used by state and tribal agencies in managing Lake Michigan fish stocks. For the AC survey, total biomass density of prey fish equaled 9.3 kg/ha, continuing a recent trend of index values above the long-term average of 5.4 kg/ha. For the fall BT, total biomass density of prey fish equaled 3.4 kg/ha, close to values observed since 2014 and well below historic numbers and those observed earlier in the 2000s. Over the period both surveys have been conducted (2004-2025), the total biomass density index had trended downward in the fall BT through the mid-2010s and appears to have stabilized at low values, while the AC survey biomass density index has remained relatively stable over the time series. Mean biomass of yearling and older (YAO) Alewife was 4.3 kg/ha in the AC survey and 0.45 kg/ha in the fall BT. Since 2014, annual survey results suggest that the catchability of YAO Alewife for the fall BT is substantially lower than the AC survey. The 2025 AC survey YAO Alewife biomass density estimate was 57% higher than the average from 2004-2024. The Alewife population of Lake Michigan appears to be composed mostly of young fish and the proportion of age-4 and older Alewife was ~5% in both surveys. Age-0 Alewife numeric density from the AC survey was 259 fish/ha in 2025, lower than the long-term mean (487 fish/ha). Biomass density of large (≥120 mm) Bloater was 3.5 kg/ha in the AC survey and 1.9 kg/ha in the fall BT. The density of small (<120 mm) Bloater was 540 fish/ha in the AC survey, the second highest value in the time series. Meanwhile, small Bloater density estimated in the fall BT was only 6.1 fish/ha. Biomass density of large Rainbow Smelt (≥90 mm) was 0.69 kg/ha in the AC survey and 0.04 kg/ha in the fall BT survey. Numeric density of small (<90 mm) Rainbow Smelt was 541 fish/ha in the AC survey, the highest value in the time series, and 41 fish/ha in the fall BT. All four prey fish species indexed only by the fall BT had below-average biomass densities. Deepwater Sculpin biomass density was 0.21 kg/ha, which makes 15 of the past 16 years with biomass <1 kg/ha. Slimy Sculpin was estimated to be 0.03 kg/ha, an order of magnitude lower than the long-term average from the fall BT. Round Goby biomass density was 0.44 kg/ha and Ninespine Stickleback density was 0.20 kg/ha, the highest value since 2007.

Lake Michigan↗
USGS2026

Advancing monitoring approaches to enhance tidal Chesapeake Bay habitat assessment for submerged aquatic vegetation, water clarity, chlorophyll a and dissolved oxygen

Water quality monitoring capacity has been declining for the Chesapeake Bay Program (CBP) at a time when information needs are growing, and data gaps exist to address critical decision-support for managers. The CBP Scientific Technical Assessment and Reporting Team is leading a Principal’s Staff Committee requested gap analyses toward understanding support needed to improve water quality monitoring and analysis programming. Advanced technologies and alternative monitoring approaches in the form of satellite-based measurements, Artificial Intelligence/Machine Learning (AI/ML) algorithms for data interpretation, continuous water quality in-situ sensor arrays, and community science efforts offer a growing portfolio of valuable opportunities for expanding data collections and analysis program capacities. However, since 1985, each of these options are examples of growing opportunities to enhance water quality assessments yet has seen limited adoption into elements of Chesapeake Bay water quality monitoring programs. Where new technologies have been adopted (e.g., shallow water continuous water quality monitoring), such temporally rich data streams have supported Bay health insights yet had limited use in regulatory water quality criteria assessment. This Scientific Technical Advisory Committee (STAC) supported workshop provided the ideal forum for engaging our CBP partnership regarding the maturity of new and evolving monitoring and analysis capacities to address program information needs while appreciating limitations with adopting new tools and approaches. Improving natural resources monitoring efficiency and effectiveness will expand the scientific and technical foundations for making robust, strategic choices on decisions for CBP Partnership community-based priorities, policies, and management actions. Workshop findings and recommendations reflect progress in science, technology, and analyses addressing long-standing programmatic limitations in data collection and analysis capacities. State-of-the-science updates highlighted in the workshop span the spectrum of efforts representing improvements, successes, remaining challenges toward operationalizing protocols, and guidance toward research, or adoption and implementation by monitoring programs.

Maryland, Pennsylvania, Virginia↗
USGS2026

Amphibian use of recently created wetlands in the Palouse region of northern Idaho, USA

Human development has resulted in the loss of natural wetlands in many regions and thus has led to amphibian habitat loss. Human-constructed wetlands are increasingly prevalent, particularly in human-modified landscapes, and can be used as breeding habitats by amphibians. It is important to identify factors influencing amphibian use of constructed wetlands to guide future wetland creation efforts. We examined wetland- and landscape-level factors influencing the presence and reproduction of native amphibians in 33 recently created (2–11 yold) wetlands within an urban-agricultural interface in northern Idaho, USA. We recorded wetland age, perimeter vegetation, and percentage of surrounding land cover as covariates and modeled detection and occupancy using Bayesian Multi-scale Occupancy Models for the three species we detected: Sierran Treefrog ( Pseudacris sierra ), Colombia Spotted Frog ( Rana luteiventris ), and Long-Toed Salamander ( Ambystoma macrodactylum ). Our results indicate that these three species can rapidly colonize recently created wetlands in an urban-agricultural interface. The effects of wetland- and landscape-scale features varied across species. Colombia Spotted Frog occupancy was greatest in older wetlands with some evidence for a negative association with more urbanized landscapes. Long Toed Salamanders and Sierran Treefrogs were not associated with wetland age but also showed some evidence of negative associations with urbanization. Long-Toed Salamanders showed evidence of using less vegetated wetlands while Sierran Treefrogs showed evidence of using more vegetated wetlands. Our results are consistent with multiple studies showing that wetlands in human-modified landscapes can provide amphibian breeding habitat, and they suggest that including vegetation plantings within recently created wetlands may promote amphibian colonization. Anecdotal observations also indicate that designing wetlands with sufficient hydroperiod for metamorphoses may be important for ensuring that newly created wetlands benefit amphibian populations.

Idaho↗
USGS2026

Occupancy rates of river otters (Lontra canadensis) in the St. Louis River Area of Concern

The St. Louis River Area of Concern (AOC), an estuarine system along the northeastern Minnesota-Wisconsin border, experienced significant ecological disturbances and degradation from unregulated industrial development during the 19 th and 20 th centuries. Recent restoration and remediation efforts in the AOC have led to substantial improvements in water quality, habitat, and fisheries populations. However, the status of wildlife populations following restoration efforts in the AOC remain largely unknown. We used remote cameras to estimate occupancy rates of river otters Lontra canadensis in the AOC and at two reference areas that had not been subjected to historical degradation. Because river otters occupy a high trophic level within these systems, we hypothesized that they would be an effective indicator species of overall habitat quality and recovery. Using data collected from June 2015 to February 2016, we developed single-season occupancy models for both summer and winter seasons. We found no differences in occupancy between the AOC and the reference sites, suggesting that river otter populations within the AOC were comparable to those in unaffected areas. Our results indicate that habitat restoration and remediation efforts in the St. Louis River estuary have been successful in promoting healthy wildlife populations.

Minnesota, Wisconsin↗
USGS2026

No detection of Batrachochytrium salamandrivorans after non-native salamander putative pet release in Massachusetts, USA

The disease caused by the amphibian chytrid fungus Batrachochytrium salamandrivorans (Bsal) has caused mass mortality of salamanders across Europe (Stegen et al. 2017; amphibians are not known to be susceptible to the disease (Martel et al. 2014). Bsal puts North American amphibian biodiversity at risk (Martel et al. 2014; Gray et al. 2015) despite imports of potentially infected amphibians (USFWS 2016; WAPTR 2018; Grear et al. 2021). Recently, the U.S. has announced the finalization of the 2016 interim rule to the Lacey Act (USFWS 2016) to restrict imports of all species of salamanders from 20 genera to the list of injurious amphibians and has added 16 genera to the injurious amphibian list in a new interim rule in response to updated research on salamander susceptibility to Bsal infection (USFWS 2025). A large-scale survey across the USA failed to detect Bsal in over 10,000 individuals (Waddle et al. 2020), and ongoing efforts by North American colleges and universities are similarly conducting Bsal surveillance without more recent detection (e.g., Hyman and Hill 2024). Concerned amphibian and disease specialists nevertheless are preparing for a Bsal invasion into North America (Grant et al. 2017; Olson et al.2024). Despite the initial survey results, the risk of Bsal incursion into North America remains due to broad host susceptibility of North American amphibian species (Gray et al. 2023). The major driver of Bsal introduction risk in the U.S. is expected to be captive amphibian release (Cunningham et al. 2015; Grear et al. 2021). Bsal primarily affects salamanders but anuran species can also be vectors (e.g., Towe et al. 2021; Monzon et al. 2022; Gray et al. 2023; Olson et al. 2024), increasing the risk of a released amphibian carrying Bsal into the natural environment (Grear et al. 2021). An early survey of pet salamanders in the United States did not detect Bsal (Klocke et al. 2017), but even one animal released with Bsal could have a major effect on local amphibians. Early detection and rapid response can improve host outcomes (Bletz et al. 2024; Gray et al. 2018), but the lack of timely knowledge about unwanted release of non-native pets to natural systems causes inevitable delay. Herein, we describe our experience responding to a report of a released non-native amphibian species, common in the pet trade (Gerson 2012; Maximo et al. 2021). We suggest improvements to early detection and rapid response efforts for amphibians and amphibian disease

Massachusetts↗
USGS2026

Tropical and subtropical coral reefs

Global declines in coral cover persist, owing to increasing ocean temperatures associated with climate change, continued coastal development, pollution, sedimentation, diseases and the destruction and overextraction of marine resources (through fishing and coral harvesting). These stressors have an impact on coral biodiversity, reef-associated fauna and the architectural complexity of reef frameworks, compromising the food security and livelihoods of the millions of people who depend on these ecosystems (virtually certain, well established). The frequency and severity of disturbances caused by heatwaves, disease outbreaks and tropical storms have increased (virtually certain, established but incomplete), curtailing the recovery time between such disturbances. This pattern is projected to continue on its current trajectory (at best) or accelerate (very likely). The ecosystem services provided by coral reefs are substantial, not only in terms of biodiversity, but also in terms of direct economic benefits (including coastal protection, livelihoods for millions and nurseries for commercial species), as well as less tangible benefits, such as cultural and aesthetic (intrinsic) value (virtually certain, well established). Conservation, restoration and regeneration efforts are under way on a global scale, but few initiatives are implemented on a long-term, sustainable basis, with socioeconomic considerations, such as livelihoods, taken into account (virtually certain, well established). A wide range of approaches and tools is being developed, many of which are designed to mitigate or halt reef declines. These are often restricted to local reef-wide projects, however, and the potential for upscaling is sometimes criticized (unresolved). Documented results are also almost always undermined by a clear disconnect between these and other policy decisions, such as the extraction and burning of fossil fuels and coastal development (likely). Regardless of scalability concerns, all programmes need to be embedded within a broader evidence-based conservation framework. Global efforts are required to facilitate reef ecosystem survival and continued function by reducing emissions and ongoing climate change (virtually certain, established but incomplete). The reefs of today will not be the reefs of tomorrow (virtually certain) and shifting baselines need to be considered when setting objectives with respect to conservation, restoration and regeneration (virtually certain, established but incomplete).

Report↗