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At least 505 records · Page 28Linked to original sources
USGS2025

Pit tag application in native freshwater mussels: Case studies across small, medium, and large rivers

Since their first use in the mid-1980s, external passive integrated transponder (PIT) tags have facilitated innovative investigations into multiple biological traits of animals. For native freshwater mussels, PIT tags are frequently used in capture-mark-recapture applications because they allow repeated, noninvasive sampling, are easy to apply, have high retention rates, and have negligible short-term effects on growth and survival. Because of these traits, resource managers and scientists are using PIT-tagged animals to estimate survival and movement of mussels associated with restoration efforts. However, consistency is limited in how PIT tags are affixed, monitored, and reported. Thus, our objectives were to (1) share our collective experiences in PIT tagging mussels across three case studies in small, medium, and large rivers and (2) propose guidelines for tagging and reporting data from PIT tag studies with native freshwater mussels to facilitate comparisons across future studies. The number of studies that have marked mussels with PIT tags has increased over the past 10 years. The ability to detect mussels using PIT tags has substantially advanced research in three areas of mussel ecology: (1) estimating vital rates (e.g., growth and survival), (2) tracking movements and behaviors of captively propagated, wild, and translocated individuals, and (3) improving our understanding of life history traits, such as reproductive timing. Each case study offers insights on tagging methods, tag loss, tag retention, and monitoring frequency across multiple species that range in conservation status from common to rare. We conclude with best-practice guidelines for placing PIT tags on freshwater mussels and a list of variables that could be reported in future studies to facilitate cross-system comparisons.

Freshwater Mollusk Biology and Conservation↗
USGS2023

Natal contributions of Kokanee salmon to Flaming Gorge Reservoir, Wyoming–Utah: An evaluation using otolith microchemistry

In a system that uses supplemental stocking to enhance a fishery that serves a dual purpose, an understanding of the contributions from natural and hatchery-produced fish is important so that hatchery resources can be appropriately allocated. Kokanee Oncorhynchus nerka were first stocked in Flaming Gorge Reservoir (FGR), Wyoming–Utah, in 1963 and serve a dual purpose as a prey resource and sport fish. Although natural recruitment occurs in the reservoir, a supplemental stocking program was initiated in 1991. We sought to identify the natal origin (i.e., natural, hatchery) of kokanee in FGR using otolith microchemistry. We evaluated return to the creel, composition of spawning aggregates, and growth of kokanee in FGR and focused on differences associated with natal origin. We analyzed kokanee otoliths that we collected from hatcheries ( n = 60) and FGR ( n = 1,003) for the strontium isotope ratio, 87 Sr/ 86 Sr, using laser ablation and a multicollector inductively coupled plasma mass spectrometer. We conducted Kruskal–Wallis tests to compare the strontium isotope ratios from the otolith edge of kokanee that we sampled from hatcheries and FGR. Based on 87 Sr/ 86 Sr ratios, we could distinguish natural-origin kokanee from 11 of the 12 hatcheries ( P < 0.01); however, the Wigwam Hatchery was not significantly different from FGR ( P = 0.84). We used model-based discriminant function analysis to assign natal origins for kokanee caught in FGR. Hatchery contribution to the population at large varied from 21 to 50% among year classes from 2014 to 2018. The percentage of hatchery origin kokanee in the creel (18–50%) was similar to what we observed in the population. Hatchery-produced kokanee contributed a higher proportion to tributary-spawning aggregates (40–90%) than shoreline-spawning aggregates (19–58%) by sample year. Growth of natural and hatchery kokanee was similar, suggesting similar performance in the system. Results from this study identify that hatchery supplementation contributes to the population and recreational harvest of kokanee in FGR. This research also provides insight into the ecology of kokanee that is useful for better understanding kokanee population dynamics in reservoir systems.

Utah, Wyoming↗
USGS2022

Round Goby captured in a North American estuary: Status and implications in the Hudson River, New York

Round Goby Neogobius melanostomus , a nonnative fish species to North America, has been rapidly expanding through the connected waterways of the Laurentian Great Lakes. Herein, we document the eastward and southern expansion of Round Goby into the Hudson River, New York, an iconic coastal estuary that drains to Long Island Sound and the Atlantic seaboard. In summer and early fall 2021, routine fish monitoring conducted by the New York State Department of Environmental Conservation documented a population of Round Goby in the tidal portion of the Hudson River. Over the course of monitoring in 2021, personnel collected 112 Round Goby between Albany, New York, and Poughkeepsie, New York, with the southernmost collection occurring approximately 140 km downstream of invasion front as reported in 2020 within the New York State Canal System. Although Round Goby previously colonized large rivers and streams in the Great Lakes watershed, there is little information about the invasion success and ecological impacts of Round Goby in estuarine environments in North America. We discuss the distribution and biological characteristics of the Hudson River Round Goby population as well as the potential ecological implications and areas of future research and monitoring for this range expansion.

New York↗
USGS2025

Invasive wild pig movement and space use in a mixed-use forest landscape, South Carolina

Invasive wild pigs ( Sus scrofa ) pose considerable ecological and economic challenges across their introduced range, and understanding their spatial ecology is critical for management. This research and accompanying dataset represents adult wild pig movement in South Carolina, United States based on 16 individuals collared in 2023-2024. Using hourly GPS collar data for 6 males and 5 females, we calculated autocorrelated kernel density estimates (AKDEs) and monthly kernel density estimates (KDEs) to characterize space use. Individual pigs had an average hourly step length of 83 m and average net displacement of 930 m. On average, pigs used 2.32 km 2 monthly, while they used 2.95 km 2 over their entire tracked period (mean = 111 days). This work aims to support management actions and future research on invasive wild pigs.

South Carolina↗
USGS2021

Moderate susceptibility to subcutaneous plague (Yersinia pestis) challenge in vaccine-treated and untreated Sonoran deer mice (Peromyscus maniculatus sonoriensis) and northern grasshopper mice (Onychomys leucogaster)

The variable response of wild mice to Yersinia pestis infection, the causative agent of plague, has generated much speculation concerning their role in the ecology of this potentially lethal disease. Researchers have questioned the means by which Y. pestis is maintained in nature and also sought methods for managing the disease. Here we assessed the efficacy of a new tool, the sylvatic plague vaccine (SPV), in wild-caught northern grasshopper mice ( Onychomys leucogaster ) and commercially acquired Sonoran deer mice ( Peromyscus maniculatus sonoriensis ). More than 40% of the animals survived a subcutaneous Y. pestis challenge of 175,000 colony forming units (over 30,000 times the white mouse 50% lethal dose) in both vaccine-treated and control groups. Our results indicate that SPV distribution is unlikely to protect adult mice from plague infection in field settings and corroborate the heterogeneous response to Y. pestis infection in mice reported by others.

Journal of Wildlife Diseases↗
USGS1989

Snowy owl

The snowy owl is a rare to uncommon, irregular winter visitor in the northeastern United States, decreasing southward in abundance except during incursion years, when it is more common and widely distributed. Although snowy owls are recorded in northern New England every winter, major incursions occur at approximately three to four year intervals. Limiting factors include food, habitat and human interference. Research is needed on the population ecology of this species and, perhaps more important, management goals must be directed towards public education emphasizing the value of snowy owls.

Book chapter↗
USGS2002

Threats to desert tortoise populations: a critical review of the literature

Decision in resource management are generally based on a combination of sociopolitical, economic, and environmental factors, and may be biased by personal values. These three components often contradict each other resulting in controversy. Controversies can usually be reduced when solid scientific evidence is used to support or refute a decision. However, it is important to recognize that data often do little to alter antagonists' positions when differences in values are the bases if the dispute. But, supporting data can make the decision more defensible, both legally and ethically, especially if the data supporting all opposing viewpoints are included in the decision-making process. Resource management decisions must be made using the best scientific information currently available. However, scientific data vary in two important measures of quality: reliability and validity. The reliability of the data is a measure of the degree to which the observations or conclusion can be repeated. Validity of the data is a measure of the degree to which the observation or conclusion reflects what actually occurs in nature. How the data are collected strongly affects the reliability of validity of ecological conclusions that can be made. Research data potentially relevant to management come from different sources, and the source often provides clues to the reliability and, to a certain extent, validity of data. Understanding the quality of data being used to make management decisions helps to separate the philosophical or value-based aspects of arguments from the objective ones, thus helping to clarify the decisions and judgments that need to be made. The West Mojave Plan is a multispecies, bioregional plan for the management of natural resources within a 9.4 million-acre area of the Mojave Desert in California. The plan addresses the legal requirements for the recovery of the desert tortoise ( Gopherus agazzizii ), a threatened species, but also covers an additional approximately 80 species of plants and animals assigned special status by the Bureau of Land Management, U. S. Fish and Wildlife Service, and California Department of Fish and Game. Within the planning area, 28 separate jurisdictions (counties, cities, towns, military installations, etc.) seek programmatic prescriptions that will facilitate streamlined environmental review, result in expedited authorization for development projects, and protect listed and unlisted species into the foreseeable future to avoid or minimize conflicts between proposed development and species' conservation and recovery. All of the scientific data available concerning the biology and management of these approximately 80 species and their habitats must be evaluated to develop a scientifically credible plan. This document provides an overview and evaluation of the knowledge of the major threats to the persistence and recovery of desert tortoise populations. I was specifically asked to evaluate the scientific veracity of the data and reports available. I summarize the data presently available with particular focus on the West Mojave Desert, evaluate the scientific integrity of the data. and identify major gaps in the available knowledge. I do not attempt to provide in-depth details on each study or threat; for more details I encourage the reader to consult the individual papers or reports city throughout this report (many of which are available at most university libraries and at the West Mojave Plan office in Riverside, California). I also do not attempt to characterize or evaluate the past or present management actions, except where they have direct bearing on evaluation of threats, nor do I attempt, for the most part, to acquire, generate, or evaluate new or existing, but uninterpreted data.

California↗
USGS2003

Forest pathology in Hawaii

Native Hawaiian forests are characterised by a high degree of endemism, including pathogens as well as their hosts. With the exceptions of koa (Acacia koa Gray), possibly maile (Alyxia oliviformis Gaud.), and, in the past, sandalwood (Santalum spp.), forest species are of little commercial value. On the other hand, these forests are immensely important from a cultural, ecological, and evolutionary standpoint. Forest disease research was lacking during the mid-twentieth century, but increased markedly with the recognition of ohia (Metrosideros polymorpha Gaud.) decline in the 1970s. Because many pathogens are themselves endemic, or are assumed to be, having evolved with their hosts, research emphasis in natural areas is on understanding host-parasite interactions and evolutionary influences, rather than disease control. Aside from management of native forests, attempts at establishing a commercial forest industry have included importation of several species of pine, Araucaria, and Eucalyptus as timber crops, and of numerous ornamentals. Diseases of these species have been introduced with their hosts. The attacking of native species by introduced pathogens is problematic - for example, Armillaria mellea (Vahl ex Fr.) Que??l. on koa and mamane (Sophora chrysophylla (Salisb.) Seem.). Much work remains to be done in both native and commercial aspects of Hawaiian forest pathology.

New Zealand Journal of Forestry Science↗
USGS2022

Great Lakes lake trout thiamine monitoring program annual report

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 have conducted in collaboration with partner agencies a cooperative program to monitor thiamine concentrations in lake trout eggs since the late 1990s. In 2021, egg thiamine concentrations were highly variable at each sampling site. No eggs samples with thiamine concentrations less than the 4 nmol/g threshold recommended for successful lake trout reproduction were collected in Lakes Superior, Huron, Erie, and Champlain. In contrast, every site in Lakes Michigan and Ontario and Cayuga Lake had some lake trout 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.

Great Lakes↗
USGS2023

Novel use of antifungal nail lacquer to treat candida bill infections in ducks

Captive wild ducks in the research colony at the USGS Eastern Ecological Science Center, Laurel, Maryland USA frequently contract Candida infections on the upper and lower bills. Various standard treatments were attempted with mixed success. Several of the Surf Scoters, especially, suffered extreme erosions of the bill leading to euthanasia prior to using this new treatment. For the past 3 years we have been using a human medical product, ciclopirox 8% nail lacquer to treat the Candida successfully. The treatment requires careful trimming and debriding of the dead tissue before applying the ciclopirox, then keeping the ducks caged away from water for 15 minutes to allow the product to dry. Standard treatment is twice weekly. For persistent cases we add oral fluconazole to the treatment regime. We have successfully treated common eider, surf scoter, white-winged scoter, black scoter, long-tailed ducks, and harlequin ducks with ciclopirox and have seen no adverse reactions.

Conference Paper↗
USGS2024

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↗
USGS2013

Host range, host ecology, and distribution of more than 11800 fish parasite species

Our data set includes 38 008 fish parasite records (for Acanthocephala, Cestoda, Monogenea, Nematoda, Trematoda) compiled from the scientific literature, Internet databases, and museum collections paired to the corresponding host ecological, biogeographical, and phylogenetic traits (maximum length, growth rate, life span, age at maturity, trophic level, habitat preference, geographical range size, taxonomy). The data focus on host features, because specific parasite traits are not consistently available across records. For this reason, the data set is intended as a flexible resource able to extend the principles of ecological niche modeling to the host–parasite system, providing researchers with the data to model parasite niches based on their distribution in host species and the associated host features. In this sense, the database offers a framework for testing general ecological, biogeographical, and phylogenetic hypotheses based on the identification of hosts as parasite habitat. Potential applications of the data set are, for example, the investigation of species–area relationships or the taxonomic distribution of host-specificity. The provided host–parasite list is that currently used by Fish Parasite Ecology Software Tool (FishPEST, http://purl.oclc.org/fishpest ), which is a website that allows researchers to model several aspects of the relationships between fish parasites and their hosts. The database is intended for researchers who wish to have more freedom to analyze the database than currently possible with FishPEST. However, for readers who have not seen FishPEST, we recommend using this as a starting point for interacting with the database.

Ecology↗
USGS2000

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↗
USGS2018

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↗
USGS2010

Ecological requirements for pallid sturgeon reproduction and recruitment in the Lower Missouri River: Annual report 2009

The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The general Comprehensive Sturgeon Research Project strategy is to integrate field and laboratory studies of sturgeon reproductive ecology, habitat requirements, and physiology to produce a predictive understanding of sturgeon population dynamics. The project scope of work is developed annually with cooperating research partners and in collaboration with the U.S. Army Corps of Engineers, Missouri River Recovery-Integrated Science Program. The research consists of several interdependent and complementary research tasks engaging multiple disciplines that primarily address spawning as a probable limiting factor in reproduction and survival of the pallid sturgeon. The research is multifaceted and is designed to provide information needed for management decisions impacting habitat restoration, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research activities and progress towards understanding of the species are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by Comprehensive Sturgeon Research Project during 2009.

Open-File Report↗
USGS2011

Preface: Multiscale feedbacks in ecogeomorphology

Geomorphic systems are known to exhibit nonlinear responses to physical&ndash;biological feedbacks (Thornes, 1985; Baas, 2002; Reinhardt et al., 2010). These responses make understanding and/or predicting system response to change highly challenging. With growing concerns over ecosystem health, a pressing need exists for research that tries to elucidate these feedbacks (Jerolmack, 2008; Darby, 2010; National Research Council, 2010). A session was convened at the Fall 2008 meeting of the American Geophysical Union (AGU) to provide an outlet for some of this truly interdisciplinary and original research, which is central to understanding geomorphic and ecological dynamics. The session attracted over 39 contributions, which were divided into two well-attended oral sessions and a very busy poster session. This special issue presents new research from the AGU session, which highlights clear physical&ndash;biological feedbacks. The aim is to bring together contrasting perspectives on biological and geomorphic feedbacks in a diversity of physiographic settings, ranging from wetlands and estuaries, through rivers, to uplands. These papers highlight biological and physical feedbacks which involve the modulation or amplification of geomorphic processes. These papers will be of interest to a core geomorphology audience, and should also draw attention from the fields of ecohydraulics, hydroecology, ecohydrology, ecomorphology, biogeochemistry and biogeography, and biogeomorphology as well as the more traditional fields of hydrology, ecology and biology. In this preface to the special issue, we a) review past contributions to the emerging field of ecogeomorphology and related disciplines, b) provide some context for how this topical special issue came to fruition, and c) summarize the contributions to this special issue.

Geomorphology↗
USGS2019

Employing an ecosystem services framework to deliver decision ready science

Public land managers have limited information to allow for the integration and balancing of multiple objectives in land management decisions including the social (cultural and health), economic (monetary and nonmonetary), and environmental aspects. In this article, we document an approach to consider the many facets of decision making by incorporating them into a decision context using an ecosystem services framework. This analysis is based on a multi-partner project led by the US Geological Survey and the US Fish and Wildlife Service to provide land management decision support for the Great Dismal Swamp National Wildlife Refuge. It is an integrated ecologic-economic analysis of baseline (current) and potential future quantities, qualities, and values of selected ecosystem services from the Refuge. Alternative management scenarios are modeled to consider the impact of specific management actions or natural disturbances on priority ecosystem services. We examine the benefits and challenges of using this framework. Key lessons learned from this effort include the mismatch in timing between physical and social science; the challenge of integrating methods from multiple disciplines; the importance of frequent communication to overcome siloed research; and the utility of an integrating framework for ecosystem services and supporting tools such as the dynamic ecosystem model.

Advances in Ecological Research↗