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At least 37 records · Page 2Linked to original sources

Great Lakes lake trout (Salvelinus namaycush) thiamine monitoring program annual report

Thiamine deficiency in lake trout eggs has been identified to induce early life-stage mortality in the Great Lakes in the 1960s through the 1990s and potentially affecting lake trout recruitment. As a results, the U.S. Geological Survey’s Great Lakes Science Center (GLSC), Eastern Ecological Science Center, and Columbia Environmental Research Center (CERC), and the State University of New York (SUNY) Brockport, in collaboration with partner agencies, have conducted a cooperative program to monitor thiamine concentrations in lake trout Salvelinus namaycush eggs since the late 1990s. In 2023, egg thiamine concentrations were highly variable at each sampling site. No egg samples with thiamine concentrations less than the 4 nmol/g threshold recommended for successful lake trout reproduction were collected in Lakes Superior or Huron. In contrast, 3 to 52% of the lake trout collected at sites in Lakes Michigan, Huron, Ontario and Champlain, and Cayuga Lake had eggs below 4 nmol/g. Time series of mean lake trout egg thiamine concentrations showed high temporal and spatial variability within the Great Lakes region.

Cayuga Lake, Lake Champlain, Lake Erie, Lake Huron↗

Identifying management-relevant research priorities for responding to disease-associated amphibian declines

A research priority can be defined as a knowledge gap that, if resolved, identifies the optimal course of conservation action. We (a group of geographically distributed and multidisciplinary research scientists) used tools from nominal group theory and decision analysis to collaboratively identify and prioritize information needs within the context of disease-associated amphibian decline , in order to develop a strategy that would support US management agency needs. We developed iterated influence diagrams to create and assess a unified research strategy. We illustrated a transparent process for identifying specific knowledge gaps in amphibian disease ecology relevant to environmental management, and then constructed a research plan to address these uncertainties. The resulting priorities include a need to: (1) understand the drivers of the community-disease relationship, (2) determine the mechanisms by which exposure to contaminants influence disease outcomes, (3) identify elements of terrestrial and aquatic habitats that stabilize host-pathogen dynamics, (4) discuss how metapopulations may be managed to reduce the speed and intensity of disease outbreaks, and (5) define the relationship between habitat management and the environmental and host microbiomes. Along with identifying research priorities for disease management, we present the details of the process used to develop a consensus plan for addressing disease-related declines in amphibians on federally managed lands of the United States.

Global Ecology and Conservation↗

Early avian research at the Savannah River Site, South Carolina: historical highlights and possibilities for the future

Avian biology and collection of baseline population data was a major part of the first decade (1951-1961) of field research at the Savannah River Site (SRS). Baseline inventories involving organisms and land-use types were part of the mission in the early contracts between the Atomic Energy Commission (now the Department of Energy) and the University of Georgia prior to the establishment of the Savannah River Ecology Laboratory (SREL) as a National Environmental Research Park Laboratory. About 27% of the SREL publications during this first decade dealt with birds. Since that time, research on the SRS landscape has expanded and broadened with less than 10% of the publications dealing with birds. SRS changed also from an agriculturally dominated area with ca. 40% open areas (fields, crops, pastures) to a timber-managed area with ca. 80% forests, 12% open areas, and 2% open water impoundments. Baseline breeding bird populations of the SRS in the 1950s were typical for the region with avian species richness and density increasing with the age and succession of the vegetation (0-26 species and densities of 0-741 pairs/km2 for the habitats surveyed). During the first decade at the SRS, the resident game bird population of Northern Bobwhites (Colinus virginianus) increased and the Mourning Dove (Zenaida rnacroura) population, a migratory upland game bird, remained stable. Current avian research efforts, as well as new opportunities to reexamine the breeding bird populations and the landscape of SRS, will provide a better understanding of the potential causes of declines of neotropical migratory birds, declines of resident and migratory game birds, and how habitat influences invasions and extinctions of breeding birds in the region. Emphasis for future research and monitoring should be on neotropical migratory bird populations in decline (Yellow-billed Cuckoo, Coccyzus americanus; Eastern Wood-Pewee, Contopus virens; Wood Thrush, Hylocichla mustelina; Prairie Warbler, Dendroica discolor; and Painted Bunting, Passerina ciris), resident species in decline (e.g., Loggerhead Shrike, Lanius ludovicianus), certain species groups (e.g., waterfowl and wading birds), important habitat, and recent invasions and extinctions of breeding species. Old growth forested wetlands should be monitored because of the large number of neotropical migratory birds that depend on this habitat in the southeastern United States. A variety of survey techniques will be needed to determine population trends: line transects, call or song playbacks, roadside point surveys (call counts for game birds), aerial surveys, and presence or absence of species within stratified areas of SRS. The SRS provides opportunity for avian research at the landscape level with the potential to solve problems important to the survival of many bird populations as well as to increase our knowledge on how to manage and conserve our avian natural resources for the future.

Book chapter↗

Global assessment of aquatic Isoëtes species ecology

Isoëtes are iconic but understudied wetland plants, despite having suffered severe losses globally mainly because of alterations in their habitats. We therefore provide the first global ecological assessment of aquatic Isoëtes to identify their environmental requirements and to evaluate if taxonomically related species differ in their ecology. The assessment resulted in an extensive new database on aquatic Isoëtes , ecological niche analyses, and descriptive species accounts. We compiled a global database that includes all known environmental data collected from 1935 to 2023 regarding aquatic Isoëtes. We then evaluated the environmental drivers of 16 species using 2,179 global records. Additionally, we used hypervolume analysis to quantify the ecological niches of the two species with the greatest number of records, finding significant differences and evidence that Isoëtes echinospora occupies a wider ecological niche than Isoëtes lacustris . Fifty-nine species (30% of the c. 200 Isoëtes species known today) were categorised as aquatic and were mainly reported in the Americas and northern Europe. About 38% of the aquatic species are threatened with extinction or are endemic to a small region, according to the International Union for Conservation of Nature's Red List in 2023. Many species were determined to be sensitive to certain water physical and chemical factors, generally preferring oligotrophic conditions such as low total phosphorus, moderate total nitrogen, moderate to low pH, and low conductivity. This analysis includes ecological data in the assessment of rare/threatened aquatic plants globally. This new database and the ecological analyses completed defined the ecological requirements of several species and identified knowledge gaps, which can aid management actions and future research. This paper highlights ecological significance and environmental sensitivities of aquatic Isoëtes . The current level of knowledge is inadequate for a large proportion of known taxa. We affirm the extreme need to support global, collaborative initiatives on which to build future conservation strategies.

Freshwater Biology↗

Planning long-term vegetation studies at landscape scales

Long-term ecological research is receiving more attention now than ever before. Two recent books, Long-term Studies in Ecology: Approaches and Alternatives , edited by Gene Likens (1989), and Long-term Ecological Research: An International Perspective , edited by Paul Risser (1991), prompt the question, “Why are these books so thin?” Except for data from paleoecological, retrospective studies (see below), there are exceptionally few long-term data sets in terrestrial ecology (Strayer et al. 1986; Tilman 1989; this volume). In a sample of 749 papers published in Ecology , Tilman (1989) found that only 1.7% of the studies lasted at least five field seasons. Only one chapter in each of the review books dealt specifically with expanding both the temporal and the spatial scales of ecological research (Berkowitz et al. 1989; Magnuson et al. 1991). Judging by the growing number of landscape-scale long-term studies, however, such as the Long-Term Ecological Research (LTER) Program (Callahan 1991), the U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP; Palmer et al. 1991), the U.S. Army’s Land Condition-Trend Analysis (LCTA) Program (Diersing et al. 1992), and various agencies’ global change research programs (CEES 1993), there is a growing interest to expand ecological research both temporally and spatially.

Book chapter↗

Sustaining visitor use in protected areas: Future opportunities in recreation ecology research based on the USA experience

Recreation ecology, the study of environmental consequences of outdoor recreation activities and their effective management, is a relatively new field of scientific study having emerged over the last 50 years. During this time, numerous studies have improved our understanding of how use-related, environmental and managerial factors affect ecological conditions and processes. Most studies have focused on vegetation and soil responses to recreation-related trampling on trails and recreation sites using indicators such as percent vegetation cover and exposed mineral soil. This applied approach has and will continue to yield important information for land managers. However, for the field to advance, more attention needs to be given to other ecosystem attributes and to the larger aspects of environmental conservation occurring at landscape scales. This article is an effort at initiating a dialog on needed advances in the field. We begin by reviewing broadly generalizable knowledge of recreation ecology, to separate what is known from research gaps. Then, based on the authors’ perspective of research in the USA and North America, several research directions are suggested as essential for continued progress in this field including theoretical development, broadening scale, integration with other disciplines, and examination of synergistic effects.

Environmental Management↗

Great Lakes lake trout (Salvelinus namaycush) thiamine monitoring program annual report

Thiamine deficiency in lake trout ( Salvelinus namaycush ) eggs has been linked to early life-stage mortality in the Great Lakes from the 1960s through the 1990s, potentially affecting lake trout recruitment. In response, the U.S. Geological Survey’s Great Lakes Science Center (GLSC), Eastern Ecological Science Center (EESC), and Columbia Environmental Research Center (CERC), and the State University of New York (SUNY) Brockport, in collaboration with partner agencies, initiated a cooperative monitoring program in the late 1990s to assess thiamine concentrations in lake trout eggs. In 2024, egg thiamine concentrations continued to show high variability across sampling sites. No samples with thiamine concentrations below the 4 nmol/g threshold recommended for successful reproduction were observed in Lakes Superior or Huron. In contrast, between 11% and 88% of lake trout sampled from sites in Lakes Michigan, Ontario, Champlain, and the Finger Lakes had egg thiamine concentrations below this critical threshold. Time series data revealed substantial temporal and spatial variation in mean lake trout egg thiamine concentrations across the Great Lakes region.

Finger Lakes, Great Lakes, Lake Champlain↗

Great Lakes lake trout (Salvelinus namaycush) thiamine monitoring program annual report

Thiamine deficiency in lake trout (Salvelinus namaycush) eggs has been linked to early life-stage mortality in the Great Lakes from the 1960s through the 1990s, potentially affecting lake trout recruitment. In response, the U.S. Geological Survey’s Great Lakes Science Center (GLSC), Eastern Ecological Science Center (EESC), and Columbia Environmental Research Center (CERC), and the State University of New York (SUNY) Brockport, in collaboration with partner agencies, initiated a cooperative monitoring program in the late 1990s to assess thiamine concentrations in lake trout eggs. In 2024, egg thiamine concentrations continued to show high variability across sampling sites. No samples with thiamine concentrations below the 4 nmol/g threshold recommended for successful reproduction were observed in Lakes Superior or Huron. In contrast, between 11% and 88% of lake trout sampled from sites in Lakes Michigan, Ontario, Champlain, and the Finger Lakes had egg thiamine concentrations below this critical threshold. Time series data revealed substantial temporal and spatial variation in mean lake trout egg thiamine concentrations across the Great Lakes region.

Lakes Superior, Michigan, Huron, Erie, Ontario, Ch↗

Captivity may broadly impede bison ecological function: Space, season, and management

American bison ( Bos bison ) were spared from numerical extinction but considered to be ecologically extinct, partially due to spatial restrictions in their former range. A key component of the ecological function of bison is their ability to adjust their spatial behaviors at multiple scales to match the seasonal distributions and availability of resources. To understand how management influences the amount and seasonality of space bison use at various scales, we estimated home range using autocorrelated kernel density estimators (95% utilization distribution) and foraging patch size by the maximum variance in first-passage time at four temporal scales (annual, growing, nongrowing, and focal seasons) for two free-ranging and three captive bison herds. The seasonal differences in space-use within management regimes and study areas were treated as nonparametric related measures while differences amongst management regimes and study areas were treated as nonparametric independent measures. Seasonal variations in space-use were detected in both management regimes, but only free-range bison depicted this pattern at the larger home range scale (p < 0.001). Free-range bison had significantly larger home ranges across seasons compared to captive bison (p < 0.001), but captive bison had larger foraging patch sizes during the growing season than free-range bison. Study areas with captive bison did not differ in their amount of space-use at any scale or season (p > 0.05). The strongest differences were apparent among study herds in annual home range size (p < 0.001) and growing season foraging patch size (p < 0.001). Our results demonstrate that captivity likely prevents bison from using their available landscape seasonally at broad scales, which could have ecological consequences for this historically nomadic herbivore. Although sociopolitical realities prevent bison restoration at a continental scale, increasing the amount of space available to bison where possible has the potential to replicate previous ecological processes. Further research can evaluate the influence of local environmental conditions on seasonality of bison space-use and can assess effects of scale on the ecological impacts of bison.

Colorado, Montana, Texas, Utah↗

Assessment of existing groundwater quality data in the Green-Duwamish watershed, Washington

The United States Geological Survey (USGS) provided technical support to the Washington Department of Ecology (Ecology) in their assessment of the role groundwater plays in contributing pollutant loading to the Green-Duwamish River near Seattle, Washington. Ecology is developing watershed hydrology models of the Green-Duwamish watershed, and need to assign realistic contaminant concentrations to the various Hydrologic Response Units represented in their models. The USGS compiled existing groundwater quality data in the Green-Duwamish watershed, and this report summarizes results and interpretation of the dataset, including identifying data gaps and needs for further research and monitoring. The sources of existing data were the USGS’s National Water Information System, Ecology’s Environmental Information Management System, and a compilation of several studies by Leidos, a scientific research company. The water-quality parameters of interest included polychlorinated biphenyl (PCB) Aroclors and congeners, phthalates, carcinogenic polycyclic aromatic hydrocarbons (cPAHs), arsenic, copper, and zinc. Results were grouped into the four subwatersheds delineated in Ecology’s hydrology models: Duwamish, Lower Green, Soos, and Upper Green. Results from the Duwamish subwatershed were further sub-divided by the USGS into the Lower Duwamish, containing land adjacent to the Lower Duwamish Waterway Superfund site, and the Upper Duwamish, containing the remaining area of the Duwamish subwatershed. Groundwater quality data in the Lower Duwamish were treated separately because there is known contamination in this area. The availability of water quality data varied by subwatershed as follows: phthalate data was only available within the Duwamish, PCB data was available within the Duwamish and Lower Green, cPAH data was available within the Duwamish, Lower Green, and Soos, and data for arsenic, copper, and zinc were available within all four subwatersheds. More than 99 percent of the available data was within the Duwamish subwatershed, identifying a need for additional monitoring of groundwater quality in the other subwatersheds.

Washington↗

Ecosystem function and services of aquatic predators in the Anthropocene

Arguments for the need to conserve aquatic predator (AP) populations often focuses on the ecological and socio-economic roles they play. Here, we summarize the diverse ecosystem functions and services connected to APs, including regulating food webs, cycling nutrients, engineering habitat, transmitting diseases/parasites, mediating ecological invasions, effecting climate, supporting fisheries, generating tourism, and providing bioinspiration. In some cases, human-driven declines and increases in AP populations have altered these ecosystem functions and services. We present a Social Ecological Framework for supporting adaptive management decisions involving APs in response to social and environmental change. We also identify outstanding questions to guide future research on the ecological functions and ecosystem services of APs in a changing world

Trends in Ecology and Evolution↗

Developing landscape-indicator models for pesticides and nutrients in streams of the Mid-Atlantic Coastal Plain

Collaborative research between the U.S. Environmental Protection Agency (USEPA), Landscape Ecology Branch, and the U.S. Geological Survey (USGS) began in 1999 to relate land use, geology, and other geographic variables to water quality and aquatic ecology in small streams of the Mid-Atlantic Coastal Plain. Results of the study will include landscape-indicator models (see inset) for stream ecological condition and for concentrations of pesticides and nutrients in ground water discharging to small streams. A base network of 174 small (typically first-order) streams was designed across a gradient of hydrogeologic and land-use settings. Additional sites were selected to represent natural watershed conditions and to relate results from the base network to downstream conditions and seasonal hydrologic variability. Benthic-community and habitat assessments were conducted at each stream; water samples from all streams were analyzed for selected pesticides, pesticide metabolites, nutrients, and major ions.

Fact Sheet↗

Eastern Ecological Science Center — Fish and aquatic animal health

Science provided by the U.S. Geological Survey (USGS) Eastern Ecological Science Center (EESC) helps to protect fish and aquatic animal health and support disease management of our Nation’s fisheries and aquatic animal populations. Our capabilities and expertise span diverse, yet highly integrated disciplines related to all aspects of biology, ecology, and animal health. Our scientists work to identify novel and emerging pathogens and diseases to assess fish and aquatic animal responses to parasites, pathogens, adverse environmental conditions, and chemical exposures. Eastern Ecological Science Center research is conducted both in laboratories and in the field in various aquatic environments ranging from headwater streams to the ocean. The EESC team provides science leadership and support for fisheries and aquatic species specialists nationwide.

Fact Sheet↗

A comprehensive inventory of communication tower infrastructure across the range of greater and Gunnison sage-grouse

We compiled and verified a comprehensive inventory dataset of communication tower infrastructure across the range of the greater sage-grouse ( Centrocercus urophasianus ) and Gunnison sage-grouse ( Centrocercus minimus ), two species of conservation concern that are viewed as ecosystem health indicators for the entire sagebrush biome within the United States. Our dataset includes all known towers with emphasis on validating construction year and month for towers built between 1990–2023. The annual spatial time series format of the data allows users to visualize, assess, and download tower locations and duration (including dates of construction and dismantlement) across the sagebrush biome of the western U.S. Tower data were acquired from publicly available infrastructure databases and records were filtered to include communication tower structures within the area of interest. Data records were validated and checked for accuracy with high resolution aerial and satellite imagery, and a subset were verified during field visits. The final filtered dataset comprises 4,322 tower sites, of which 3,528 tower site locations were verified via satellite imagery or field visits, and 794 were unverified tower sites (tower presence could not be confirmed via satellite imagery). Each tower record includes geographic coordinates, structure height, estimated date of construction, number of towers at each site, and, if applicable, date of dismantlement. The data product closes spatiotemporal gaps and resolves discrepancies present in other public versions of similar data and can be used in ecological research, infrastructure planning/siting/permitting, decision support tools for biological or landscape management, environmental assessments, or general use pertaining to the historic and current locations of communication infrastructure across sagebrush ecosystems.

western united States↗

Biology and impacts of Pacific Islands invasive species. 14. Sus scrofa the feral pig (Artiodactyla: Suidae)

Feral pigs ( Sus scrofa L.) are perhaps the most abundant, widespread, and economically significant large introduced vertebrate across the Pacific island region. Unlike many other nonnative invasive species, feral pigs have both cultural and recreational importance in the region, complicating their management. Today, Pacific island feral pigs are a mixture of several strains of domestic swine, Asiatic wild boar, and European wild boar. Due to their generalist diet and rooting behavior, feral pigs alter soils and watersheds and negatively impact native and nonnative flora and fauna. As a result, feral pigs have played a role in the extinction of several species of plants and animals on Pacific islands and have negative effects on both ecotourism and agricultural industries in the region. Despite numerous published studies on feral pigs in the Pacific island region, of which the majority include systematic analyses of original empirical data, some fundamental aspects of feral pig ecology remain poorly characterized, at least partly due to the remote and inaccessible environments that they often inhabit. To address these knowledge gaps, effort should be made to integrate research conducted outside the Pacific island region into local management strategies. This review summarizes the origins, history, ecology, environmental effects, and current management of feral pigs in the Pacific island region; integrates regional scientific findings with those of other insular and continental systems; and identifies current knowledge gaps requiring further research to inform the ecology and management of this impactful invasive species.

Hawai'i↗

Ecological distribution and population physiology defined by proteomics in a natural microbial community

An important challenge in microbial ecology is developing methods that simultaneously examine the physiology of organisms at the molecular level and their ecosystem level interactions in complex natural systems. We integrated extensive proteomic, geochemical, and biological information from 28 microbial communities collected from an acid mine drainage environment and representing a range of biofilm development stages and geochemical conditions to evaluate how the physiologies of the dominant and less abundant organisms change along environmental gradients. The initial colonist dominates across all environments, but its proteome changes between two stable states as communities diversify, implying that interspecies interactions affect this organism's metabolism. Its overall physiology is robust to abiotic environmental factors, but strong correlations exist between these factors and certain subsets of proteins, possibly accounting for its wide environmental distribution. Lower abundance populations are patchier in their distribution, and proteomic data indicate that their environmental niches may be constrained by specific sets of abiotic environmental factors. This research establishes an effective strategy to investigate ecological relationships between microbial physiology and the environment for whole communities in situ .

Molecular Systems Biology↗

Development of ecological indicator guilds for land management

Agency land-use must be efficiently and cost-effectively monitored to assess conditions and trends in ecosystem processes and natural resources relevant to mission requirements and legal mandates. Ecological Indicators represent important land management tools for tracking ecological changes and preventing irreversible environmental damage in disturbed landscapes. The overall objective of the research was to develop both individual and integrated sets (i.e., statistically derived guilds) of Ecological Indicators to: quantify habitat conditions and trends, track and monitor ecological changes, provide early warning or threshold detection, and provide guidance for land managers. The derivation of Ecological Indicators was based on statistical criteria, ecosystem relevance, reliability and robustness, economy and ease of use for land managers, multi-scale performance, and stress response criteria. The basis for the development of statistically based Ecological Indicators was the identification of ecosystem metrics that analytically tracked a landscape disturbance gradient.

Report↗

Integrating theory and empirical patterns: Fish body size distributions, life history traits, and environmental flows in streams

Individual size distributions (ISDs) are prominent in ecological research and may support resource managers with ecosystem-scale objectives. We use a database of individual size measurements for US stream fishes to test for direct and indirect effects of traits, flow regimes, and land use on the interspecific ISD exponent. Path analysis indicates that traits have strong, direct effects on ISD. Flow and land use effects on the exponent are largely indirectly mediated by their influences on species traits. ISD exponents increase (abundances of larger-bodied individuals increase, relative to smaller-bodied) when environments favor higher trophic levels, warmer thermal tolerances, and periodic life histories. Alternatively, ISD exponents decrease in systems that favor opportunistic life histories. Our flexible modeling framework that includes direct and indirect effects of traits, flow regimes, and land use on ISD could be expanded to incorporate additional variables that interact with flow (e.g., temperature and physical habitat) to assess of effects of multiple stressors on aquatic ecosystem functioning.

Science Advances↗