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At least 307 records · Page 17Linked to original sources
USGS2006

Restoration of breeding by snowy plovers following protection from disturbance

Promoting recreation and preserving wildlife are often dual missions for land managers, yet recreation may impact wildlife. Because individual disturbances are seemingly inconsequential, it is difficult to convince the public that there is a conservation value to restricting recreation to reduce disturbance. We studied threatened western snowy plovers (Charadrius alexandrinus nivosus) at a public beach (Sands Beach, Coal Oil Point Reserve) in Santa Barbara, California (USA) before and during a period when a barrier directed foot traffic away from a section of upper beach where snowy plovers roost. The barrier reduced disturbance rates by more than half. Snowy plovers increased in abundance (throughout the season) and their distribution contracted to within the protected area. Snowy plovers that were outside the protected area in the morning moved inside as people began using the beach. Experiments with quail eggs indicated an 8% daily risk of nest trampling outside the protected area. Before protection, plovers did not breed at Coal Oil Point. During protection, snowy plovers bred in increasing numbers each year and had high success at fledging young. These results demonstrate how recreational disturbance can degrade habitat for shorebirds and that protecting quality habitat may have large benefits for wildlife and small impacts to recreation. ?? Springer 2006.

Biodiversity and Conservation↗
USGS2020

Refining genetic boundaries for Agassiz’s desert tortoise (Gopherus agassizii) in the western Sonoran Desert: The influence of the Coachella Valley on gene flow among populations in southern California

Understanding the influence of geographic features on the evolutionary history and population structure of a species can assist wildlife managers in delimiting genetic units (GUs) for conservation and management. Landscape features including mountains, low elevation depressions, and even roads can influence connectivity and gene flow among Agassiz’s desert tortoise (Gopherus agassizii) populations. Substantial changes in the landscape of the American Southwest occurred during the last six million years (including the formation of the Gulf of California and the lower Colorado River), which shaped the distribution and genetic structuring of tortoise populations. The area northwest of the Gulf of California is occupied by the Salton Trough, including the Coachella Valley at its northern end. Much of this area is below sea level and unsuitable as tortoise habitat, thus forming a potential barrier for gene flow. We assessed genetic relationships among three tortoise populations separated by the Coachella Valley. Two adjacent populations were on the east side of the valley in the foothills of the Cottonwood and Orocopia mountains separated by Interstate 10. The third population, Mesa, was located about 87 km away in the foothills of the San Bernardino Mountains at the far northwestern tip of the valley. The Cottonwood and Orocopia localities showed genetic affiliation with the adjacent Colorado Desert GU immediately to the east, and the Mesa population exhibited affiliation with both the Southern Mojave and Colorado Desert GUs, despite having a greater geographic distance (0.5x–1.5x greater) to the Colorado Desert GU. The genetic affiliation with the Colorado Desert GU suggests that the boundary for that GU needs to be substantially extended to the west to include the desert tortoise populations around the Coachella Valley. Their inclusion in the Colorado Desert GU may benefit these often overlooked populations when recovery actions are considered.

California↗
USGS2011

Could residual oil from the Exxon Valdez spill create a long-term population "sink" for sea otters in Alaska?

Over 20 years ago, the Exxon Valdez oil tanker spilled 42 million L of crude oil into the waters of Prince William Sound, Alaska, USA. At the time of the spill, the sea otter (Enhydra lutris) population inhabiting the spill area suffered substantial acute injuries and loss. Subsequent research has resulted in one of the best-studied species responses to an oil spill in history. However, the question remains: Is the spill still influencing the Prince William Sound sea otter population? Here we fit time-varying population models to data for the sea otter population of western Prince William Sound to quantify the duration and extent of mortality effects from the spill. We hypothesize that the patchy nature of residual oil left in the environment has created a source-sink population dynamic. We fit models using the age distributions of both living and dying animals and estimates of sea otter population size to predict the number of sea otters in the hypothesized sink population and the number lost to this sink due to chronic exposure to residual oil. Our results suggest that the sink population has remained at just over 900 individuals (95% CI: 606-960) between 1990 and 2009, during which time prime-age survival remained 2-6% below pre-spill levels. This reduced survival led to chronic losses of ???900 animals over the past two decades, which is similar in magnitude to the number of sea otter deaths documented in western Prince William Sound during the acute phase of the spill. However, the unaffected source population appears to be counterbalancing these losses, with the model indicating that the sea otter population increased from ???2150 individuals in 1990 to nearly 3000 in 2009. The most optimistic interpretation of our results suggests that mortality effects dissipated between 2005 and 2007. Our results suggest that residual oil can affect wildlife populations on time scales much longer than previously believed and that cumulative chronic effects can be as significant as acute effects. Further, source-sink population dynamics can explain the slow recovery observed in the spill-affected western Prince William Sound sea otter population and are consistent with available data. ??2011 by the Ecological Society of America.

Ecological Applications↗
USGS2018

Survival and cause-specific mortality of translocated female mule deer in southern New Mexico, USA

Context: Many mule deer ( Odocoileus hemionus ) populations in New Mexico have failed to recover from previous population declines, while some populations near urban areas have increased, resulting in more frequent human–wildlife conflicts. Translocations were used in an effort to simultaneously reduce an urban mule deer population and augment two low-density populations in south-western New Mexico, USA. Aims: Because of insufficient monitoring, the efficacy of many ungulate translocations is unknown. Our goal was to monitor cause-specific mortality and 1 year post-release survival of mule deer translocated during 2013 and 2014. We compared survival rates of mule deer released with a hard- versus soft-release during the 2014 translocation. Methods: . We translocated 218 mule deer in 2013 and 2014 into the Peloncillo Mountains (PM) and San Francisco River Valley (SFRV); 106 adult female mule deer were fitted with telemetry collars to determine cause-specific mortality and estimate survival 1 year post-release. All deer were hard-released in 2013. In 2014, translocated mule deer were either held in a soft-release pen (0.81 ha) for approximately 3 weeks or hard-released into their new environment. We used a Kaplan–Meier approach to estimate survival of translocated mule deer at each release area and to compare survival of mule deer translocated using each release method (i.e. hard- versus soft-release). Key results: In 2013–14, survival of hard-released deer in the PM was 0.627 (s.e. = 0.09), compared with 0.327 (s.e. = 0.10) in the SFRV. In 2014–15, survival of hard–released deer in the PM was 0.727 (s.e. = 0.13) and survival of soft-released deer was 0.786 (s.e. = 0.11). In the SFRV, survival of hard- and soft-released deer was 0.656 (s.e. = 0.14) and 0.50 (s.e. = 0.16), respectively. Causes of mortality were predation (51%), potential disease (9%; blue tongue or epizootic haemorrhagic disease), accident (5%), poaching (5%) and unknown (20%). Conclusions: Translocations can be an effective management tool to augment populations of mule deer while reducing overabundant urban populations. Soft-released mule deer did not have higher survival than hard-released mule deer, although the length and conditions of the acclimation period were limited in our study. Implications: Overabundant mule deer populations in urban areas may serve as sources of animals to bolster declining populations. Soft-release pens of smaller size and short period of acclimation did not influence survival.

New Mexico↗
USGS1980

Wildlife hazards from Furadan 3G applications to rice in Texas

Mortality of birds, fish, frogs, crayfish, earthworms, and nontarget insects occurred in rice fields after treatments of Furadan 3G granules in 3 Texas counties in 1970 and 1973-75. Three western sandpipers ( Ereunetes mauri ), 1 pectoral sandpiper ( Erolia melanotos ), and 2 red-winged blackbirds ( Agelaius phoeniceus ) were found dead or moribund between 17 and 24 hours after treatment. Cricket frogs ( Acris crepitans blanchardi ) were intoxicated 15 minutes post-treatment, and mosquito fish ( Gambusia affinis ) showed effects 1 hour post-treatment. Mortality of mosquito fish, Gulf menhaden (Brevoortia patronus), Atlantic croaker (Micropogon undulatus), and European carp ( Cyprinus carpio ) usually occurred between 24 and 28 hours after treatment. Mortality of frogs, crayfish, and nontarget insects generally occurred in rice field water between 1 and 45 hours after treatment. Mortality of earthworms in soil persisted for 52 hours. As a replacement for aldrin in Texas rice fields, Furadan 3G appeared to cause less mortality of birds than aldrin, but Furadan 3G was toxic to birds, fish, and invertebrates.

Texas↗
USGS2016

Nuclear and mitochondrial DNA analyses of golden eagles (Aquila chrysaetos canadensis) from three areas in western North America; initial results and conservation implications

Understanding the genetics of a population is a critical component of developing conservation strategies. We used archived tissue samples from golden eagles ( Aquila chrysaetos canadensis ) in three geographic regions of western North America to conduct a preliminary study of the genetics of the North American subspecies, and to provide data for United States Fish and Wildlife Service (USFWS) decision-making for golden eagle management. We used a combination of mitochondrial DNA (mtDNA) D-loop sequences and 16 nuclear DNA (nDNA) microsatellite loci to investigate the extent of gene flow among our sampling areas in Idaho, California and Alaska and to determine if we could distinguish birds from the different geographic regions based on their genetic profiles. Our results indicate high genetic diversity, low genetic structure and high connectivity. Nuclear DNA Fst values between Idaho and California were low but significantly different from zero (0.026). Bayesian clustering methods indicated a single population, and we were unable to distinguish summer breeding residents from different regions. Results of the mtDNA AMOVA showed that most of the haplotype variation (97%) was within the geographic populations while 3% variation was partitioned among them. One haplotype was common to all three areas. One region-specific haplotype was detected in California and one in Idaho, but additional sampling is required to determine if these haplotypes are unique to those geographic areas or a sampling artifact. We discuss potential sources of the high gene flow for this species including natal and breeding dispersal, floaters, and changes in migratory behavior as a result of environmental factors such as climate change and habitat alteration. Our preliminary findings can help inform the USFWS in development of golden eagle management strategies and provide a basis for additional research into the complex dynamics of the North American subspecies.

Alaska, California, Idaho, Oregon↗
USGS2011

A bibliography of literature pertaining to plague ( Yersinia pestis )

Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis . Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis , management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google ( http://www.google.com ), Google Scholar ( http://scholar.google.com ), SciVerse Scopus ( http://www.scopus.com ), ISI Web of Knowledge ( http://apps.isiknowledge.com ), and the USGS Library's Digital Desktop ( http://library.usgs.gov ). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.

Open-File Report↗
USGS2024

Joint spatial modeling bridges the gap between disparate disease surveillance and population monitoring efforts informing conservation of at-risk bat species

White-Nose Syndrome (WNS) is a wildlife disease that has decimated hibernating bats since its introduction in North America in 2006. As the disease spreads westward, assessing the potentially differential impact of the disease on western bat species is an urgent conservation need. The statistical challenge is that the disease surveillance and species response monitoring data are not co-located, available at different spatial resolutions, non-Gaussian, and subject to observation error requiring a novel extension to spatially misaligned regression models for analysis. Previous work motivated by epidemiology applications has proposed two-step approaches that overcome the spatial misalignment while intentionally preventing the human health outcome from informing estimation of exposure. In our application, the impacted animals contribute to spreading the fungus that causes WNS, motivating development of a joint framework that exploits the known biological relationship. We introduce a Bayesian, joint spatial modeling framework that provides inferences about the impact of WNS on measures of relative bat activity and accounts for the uncertainty in estimation of WNS presence at non-surveyed locations. Our simulations demonstrate that the joint model produced more precise estimates of disease occurrence and unbiased estimates of the association between disease presence and the count response relative to competing two-step approaches. Our statistical framework provides a solution that leverages disparate monitoring activities and informs species conservation across large landscapes. Stan code and documentation are provided to facilitate access and adaptation for other wildlife disease applications.

Journal of Agricultural, Biological and Environmen↗
USGS2012

Foreword: Contributions of Arctic PRISM to monitoring western hemispheric shorebirds

Long-term monitoring of populations is of paramount importance to understanding responses of organisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, the congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for examples, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife Internationals and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis of proportions of species' populations which they contain. The size, and trends in size, of a species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and the U.S. Shorebird Conservation Plans. Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions. PRISM members evaluated ongoing and potential monitoring approached to address 74 taxa (including subspecies) and proposed a combination of arctic and boreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.

Studies in Avian Biology↗
USGS2012

Contributions of Arctic PRISM to monitoring western hemispheric shorebirds

Long-term monitoring of populations is of paramount importance to understanding responses oforganisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly migratory nature and ranges that extend into highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, they congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for example, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife International and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis ofproportions of species' populations which they contain. The size, and trends in size, ofa species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and U.S. Shorebird Conservation Plans (Donaldson et al. 2000, Brown et aL 2001). Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions (Bart et al. 2002). PRISM members evaluated ongoing and potential monitoring approaches to address 74 taxa (including subspecies) and proposed a combination of arctic andboreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.

Book chapter↗
USGS2022

A user guide to selecting invasive annual grass spatial products for the western United States

Invasive annual grasses (IAGs)—including Bromus tectorum (cheatgrass), Taeniatherum caput-medusae (medusahead), and Ventenata dubia (ventenata) species—present significant challenges for rangeland management by altering plant communities, impacting ecosystem function, reducing forage for wildlife and livestock, and increasing fire risk. Numerous spatial data products are used to map IAGs, and understanding the similarities, differences, and potential tradeoffs among these products is key to selecting the right maps for specific applications. This short guide outlines considerations for selecting regional- and national-scale spatial data to support the management of IAGs.

western United States↗
USGS2016

Amphibian dynamics in constructed ponds on a wildlife refuge: developing expected responses to hydrological restoration

Management actions are based upon predictable responses. To form expected responses to restoration actions, I estimated habitat relationships and trends (2002–2015) for four pond-breeding amphibians on a wildlife refuge (Montana, USA) where changes to restore historical hydrology to the system greatly expanded (≥8 times) the flooded area of the primary breeding site for western toads ( Anaxyrus boreas ). Additional restoration actions are planned for the near future, including removing ponds that provide amphibian habitat. Multi-season occupancy models based on data from 15 ponds sampled during 7 years revealed that the number of breeding subpopulations increased modestly for Columbia spotted frogs ( Rana luteiventris ) and was stationary for long-toed salamanders ( Ambystoma macrodactylum ) and Pacific treefrogs ( Pseudacris regilla ). For these three species, pond depth was the characteristic that was associated most frequently with occupancy or changes in colonization and extinction. In contrast, a large decrease in colonization by western toads explained the decline from eight occupied ponds in 2002 to two ponds in 2015. This decline occurred despite an increase in wetland area and the colonization of a newly created pond. These changes highlight the challenges of managing for multiple species and how management responses can be unpredictable, possibly reducing the efficacy of targeted actions.

Hydrobiologia↗
USGS2006

Predictable hotspots and foraging habitat of the endangered short-tailed albatross (Phoebastria albatrus) in the North Pacific: Implications for conservation

The short-tailed albatross ( Phoebastria albatrus ) is a rare and endangered seabird that ranges widely over the northern North Pacific. Populations are slowly recovering but birds face several threats at sea, in particular the incidental capture of birds in long-line fisheries. Conservation efforts are hampered by a lack of information about the at-sea distribution of this species, especially knowledge of where it may predictably co-occur with long-line fishing effort. During 18 years of transiting the Aleutian Islands Unit of the Alaska Maritime National Wildlife Refuge on a research vessel, we observed short-tailed albatross on 65 occasions. They were consistently observed near Ingenstrem Rocks (Buldir Pass) in the western Aleutians and near Seguam Pass in the central Aleutians. Based on the oceanographic characteristics of the locations where we saw most of the birds, we hypothesized that short-tailed albatross “hotspots” were located where tidal currents and steep bottom topography generate strong vertical mixing along the Aleutian Archipelago. As a test of this hypothesis, we analyzed a database containing 1432 opportunistic observations of 2463 short-tailed albatross at sea in the North Pacific. These data showed that short-tailed albatross were closely associated with shelf-edge habitats throughout the northern Gulf of Alaska and Bering Sea. In addition to Ingenstrem Rocks and Seguam Pass, important hotspots for short-tailed albatross in the Aleutians included Near Strait, Samalga Pass, and the shelf-edge south of Umnak/Unalaska islands. In the Bering Sea, hotspots were located along margins of Zhemchug, St. Matthews and Pervenets canyons. Because these short-tailed albatross hotspots are predictable, they are also protectable by regulation of threatening activities at local spatial scales.

Deep-Sea Research Part II: Topical Studies in Ocea↗
USGS2011

Wind energy and wildlife research at the Forest and Rangeland Ecosystem Science Center

The United States has embarked on a goal to increase electricity generation from clean, renewable sources by 2012. Towards this end, wind energy is emerging as a widely distributed form of renewable energy throughout the country. The national goal is for energy from wind to supply 20 percent of the country's electricity by 2030. As with many land uses, trade-offs exist between costs and benefits. New wind developments are occurring rapidly in parts of the United States, often leaving little time for evaluation of potential site-specific effects. These developments are known to affect wildlife, directly from fatality due to collision with the infrastructure and indirectly from loss of habitat and migration routes. The Department of the Interior, in particular, is challenged to balance energy development on public lands and also to conserve fish and wildlife. The Secretary of the Interior has proposed a number of initiatives to encourage responsible development of renewable energy. These initiatives are especially important in the western United States where large amounts of land are being developed or evaluated for wind farms.

Fact Sheet↗
USGS2015

New summer areas and mixing of two greater sandhill crane populations in the Intermountain West

Population delineation throughout the annual life cycle for migratory birds is needed to formulate regional and national management and conservation strategies. Despite being well studied continentally, connectivity of sandhill crane Grus canadensis populations throughout the western portion of their North American range remains poorly described. Our objectives were to 1) use global positioning system satellite transmitter terminals to identify summer distributions for the Lower Colorado River Valley Population of greater sandhill cranes Grus canadensis tabida and 2) determine whether intermingling occurs among any of the western greater sandhill crane populations: Rocky Mountain Population, Lower Colorado River Valley Population, and Central Valley Population. Capture and marking occurred during winter and summer on private lands in California and Idaho as well as on two National Wildlife Refuges: Cibola and Sonny Bono Salton Sea National Wildlife Refuges. A majority of marked greater sandhill cranes summered in what is established Lower Colorado River Valley Population breeding areas in northeastern Nevada and southwestern Idaho. A handful of greater sandhill cranes summered outside of traditional breeding areas in west-central Idaho around Cascade Reservoir near Donnelly and Cascade, Idaho. For example, a greater sandhill crane colt captured near Donnelly in July 2014 survived to winter migration and moved south to areas associated with the Rocky Mountain Population. The integration of the greater sandhill crane colt captured near Donnelly provides the first evidence of potential intermingling between the Lower Colorado River Population and Rocky Mountain Population. We suggest continued marking and banding efforts of all three western populations of greater sandhill cranes will accurately delineate population boundaries and connectivity and inform management decisions for the three populations.

Arizona, California, Idaho↗
USGS2021

Evaluating common raven take for greater sage-grouse in Oregon’s Baker County Priority Conservation Area and Great Basin Region

The common raven ( Corvus corax ; raven) is a nest predator of species of conservation concern, such as the greater sage-grouse ( Centrocercus urophasianus ). Reducing raven abundance by take requires authorization under the Migratory Bird Treaty Act. To support U.S. Fish and Wildlife Service’s take decisions (e.g., those that authorize killing a specified proportion or number of individuals annually in a defined area), including the most recent one for Oregon’s Baker County Priority Area for Conservation (PAC), we modeled raven population dynamics under hypothetical scenarios with take rates ranging from below to above the maximum sustained yield (MSY; i.e., tr msy = 0.01-0.60). We fit a Bayesian state-space logistic model to estimate abundance based on the Breeding Bird Survey route-level count data for the PAC during 1997-2019 and Great Basin Region (GBR) during 1968-2019. We predicted abundance for 2019-2030 and evaluated potential take levels (PTL) for the PAC and GBR. Abundance averaged 682 (SE = 93) for the PAC during 1997-2019 and 333,027 (SE = 20,504) for the GBR during 1968-2019. With take rates between 0.41 and 0.60, predicted abundance averaged 308 (SD = 405) for the PAC and 142,258 (SD = 53,474) for the GBR during 2019-2030. With management factor F = 0.75-2 for takes ranging from below to above the MSY, the PTL 50 th percentiles were 150-401 yr -1 for the PAC and 60,457-161,219 yr -1 for the GBR. Our modeling framework is flexible and can be part of a comprehensive management strategy for ravens in the western United States.

California, Idaho, Nevada, Oregon, Utah↗
USGS2005

Effects of prescribed fire in the coastal prairies of Texas

Prescribed fire is widely applied for habitat management in coastal ecosystems. Fire management plans typically list a variety of objectives for prescribed burning, including succession management, promotion of native flora and fauna, providing habitat for species of importance, wildfire risk reduction (fuels management), as well as reduction and/or prevention of invasive species. In most cases, the information needed to determine the degree to which management objectives are met is not available. This study sought to provide an assessment of key objectives of fire management at the U.S. Fish and Wildlife Service (USFWS) Texas Mid-coast National Wildlife Refuge Complex. The main purpose of this work was to provide information and recommendations that will support Region 2 of the USFWS in the conduct of their fire and habitat management activities in the Western Gulf coast region. There were four main components of this project: (1) a historical analysis of the role of fire in this ecosystem, (2) the development of standard methodology for assessing and monitoring fire effects in this system, (3) an evaluation of the effects of prescribed burning on the habitat being managed, and (4) an evaluation of the effects of burning on select fauna of special concern. A team of researchers, including some from the U.S. Geological Survey (USGS), Southeast Missouri State University, and Louisiana State University were involved in the various components of this project. Extensive support by USFWS personnel, both at the Texas Mid-coast National Wildlife Refuge Complex and in the Regional Office (Region 2, USFWS), was a key component in this work. Data from the three years of this study were combined with the results of previous USGS studies performed at the site to strengthen our conclusions.

Open-File Report↗