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At least 73 records · Page 4Linked to original sources

Range-wide relative abundance of Pyrgus centaureae wyandot (W.H. Edwards, 1863) (Appalachian Grizzled Skipper)

The US Fish and Wildlife Service has designated the butterfly Pyrgus centaureae wyando t (Appalachian Grizzled Skipper [AGS]) to be at-risk, based on its declining populations and the lack of information on its status. Our objective was to conduct range-wide surveys to locate extant AGS colonies and to quantify the number of AGS observed at each location. From 2021 to 2024, we conducted 284 surveys in 25 unique (i.e., distinct) counties in 8 states (Maryland, Michigan, New York, North Carolina, Ohio, Pennsylvania, Virginia, and West Virginia). We found AGS in only 2 counties: Alleghany County, VA, and Greenbrier County, WV. AGS were observed 180 times in these counties. Our results can inform US Fish and Wildlife decisions about where and how future AGS conservation efforts can be implemented.

Northeastern Naturalists

Strategic habitat conservation for beach mice: Estimating management scenario efficiencies

The Perdido Key beach mouse ( Peromyscus polionotus trissyllepsis ), Choctawhatchee beach mouse ( P. p. allophrys ), and St. Andrew beach mouse ( P. p. peninsularis ) are 3 federally endangered subspecies that inhabit coastal dunes of Alabama and Florida, USA. Conservation opportunities for these subspecies are limited and costly. Consequently, well‐targeted efforts are required to achieve their downlisting criteria. To aid the development of targeted management scenarios that are designed to achieve downlisting criteria, we developed a Bayesian network model that uses habitat characteristics to predict the probability of beach mouse presence at a 30‐m resolution across a portion of the Florida Panhandle. We then designed alternative management scenarios for a variety of habitat conditions for coastal dunes. Finally, we estimated how much area is needed to achieve the established downlisting criterion (i.e., habitat objective) and the amount of effort needed to achieve the habitat objective (i.e., management efficiency). The results suggest that after 7 years of post‐storm recolonization, habitat objectives were met for Perdido Key (within its Florida critical habitat) and Choctawhatchee beach mice. The St. Andrew beach mouse required 5.14 km 2 of additional critical habitat to be protected and occupied. The St. Andrew beach mouse habitat objective might be achieved by first restoring protected critical habitat to good dune conditions and then protecting or restoring the unprotected critical habitat with the highest predicted probability of beach mouse presence. This scenario provided a 28% increase in management efficiency compared to a scenario that randomly protected or restored undeveloped unprotected critical habitat. In total, when coupled with established downlisting criteria, these quantitative and spatial decision support tools could provide insight into how much habitat is available, how much more is needed, and targeted conservation or restoration efforts that might efficiently achieve habitat objectives.

Alabama, Florida

Hierarchical model analysis of the Atlantic Flyway Breeding Waterfowl Survey

We used log-linear hierarchical models to analyze data from the Atlantic Flyway Breeding Waterfowl Survey. The survey has been conducted by state biologists each year since 1989 in the northeastern United States from Virginia north to New Hampshire and Vermont. Although yearly population estimates from the survey are used by the United States Fish and Wildlife Service for estimating regional waterfowl population status for mallards (Anas platyrhynchos), black ducks (Anas rubripes), wood ducks (Aix sponsa), and Canada geese (Branta canadensis), they are not routinely adjusted to control for time of day effects and other survey design issues. The hierarchical model analysis permits estimation of year effects and population change while accommodating the repeated sampling of plots and controlling for time of day effects in counting. We compared population estimates from the current stratified random sample analysis to population estimates from hierarchical models with alternative model structures that describe year to year changes as random year effects, a trend with random year effects, or year effects modeled as 1-year differences. Patterns of population change from the hierarchical model results generally were similar to the patterns described by stratified random sample estimates, but significant visibility differences occurred between twilight to midday counts in all species. Controlling for the effects of time of day resulted in larger population estimates for all species in the hierarchical model analysis relative to the stratified random sample analysis. The hierarchical models also provided a convenient means of estimating population trend as derived statistics from the analysis. We detected significant declines in mallard and American black ducks and significant increases in wood ducks and Canada geese, a trend that had not been significant for 3 of these 4 species in the prior analysis. We recommend using hierarchical models for analysis of the Atlantic Flyway Breeding Waterfowl Survey.

Journal of Wildlife Management

Organochlorines and mercury in osprey eggs from the eastern United States

Organochlorine and mercury concentrations were determined in Osprey eggs collected from Maryland, Virginia, and Massachusetts during 1986-87. DDE concentrations were significantly different among locations. Median DDE concentrations did not decline significantly in eggs from Glenn L. Martin National Wildlife Refuge, Maryland, between 1973 and 1986. The median DDE residue for eggs from Martin Refuge in 1986 surpassed the value associated with 10% eggshell thinning, but was below the value associated with production of 1.0 young per active nest, a level assumed to represent a stable population. DDD, DDT, dieldrin, PCB, and mercury residues in all eggs appeared insignificant with regard to potential effects on shell thickness or reproduction. DDE and PCB residues were lower in eggs collected in 1986-87 than in those collected in the 1970s for each area. DDD, DDT, and dieldrin were not detected in Martin Refuge eggs in 1986, representing a significant reduction since 1973. DDD, DDT, and dieldrin levels in Massachusetts and Virginia eggs in 1986-87 were similar to those in eggs from the 1970s for each state. Mercury residues in eggs from Martin Refuge may be increasing and although not significant in this study, may warrant future monitoring.

Journal of Raptor Research

Ecological study of ruffed grouse broods in Virginia

The Ruffed Grouse ( Bonasa umbellus ), commonly called "pheasant" throughout the southern Appalachian region, is a popular game bird in the mountains of Virginia. Unfortunately, however, the grouse populations in this State have declined noticeably during the past fifty years. Because of this, special field studies were designed through the cooperation of the U. S. Fish and Wildlife Service and U. S. Forest Service, which would provide information that could be used in devising more efficient grouse management practices. As part of this program, I was assigned to investigate the ecology and habits of this species in the Shenandoah Mountains during the spring and summer of 1941. These studies were conducted within the George Washington National Forest in northwestern Augusta County, southwestern Rockingham County, and northeastern Highland County, Virginia.

The Auk

Interspecific brood parasitism of a greater sage-grouse brood by chukar in Nevada

Greater sage-grouse ( Centrocercus urophasianus ; hereafter, sage-grouse) populations have declined across their range, resulting in high conservation concerns among state and federal wildlife managers. While interspecific nest parasitism by chukar ( Alectoris chukar ) on sage-grouse nests has been observed previously, the parasitic effects benefiting or harming the reproduction of either species are unknown. Additionally, while chukar eggs have been documented in sage-grouse nests previously, we know of no documented occurrences of chukar chicks parasitizing sage-grouse broods. Here, we report a novel observation of interspecific brood parasitism on a 9-day-old sage-grouse brood by a chukar chick in the Virginia Mountains of northwestern Nevada. Because chukar are an introduced exotic species whose western North American distribution largely overlaps sage-grouse distribution, understanding the dynamics and implications of brood parasitism may inform wildlife management strategies and conservation efforts for sage-grouse throughout their range.

Nevada

Causes of mortality in common loons

Summarized are necropsy results from 222 carcasses of Common Loons ( Gavia immer ) submitted to the National Wildlife Health Research Center from 1976 through 1991. The carcasses were from 18 states, and 10 or more birds each were from Minnesota, Florida, Virginia, Michigan, Wisconsin, Maine, and North Carolina. Seventy-three (33%) carcasses were emaciated, and in some of these birds emaciation was thought to be related to exposure to mercury. OVer 40% of these emaciated birds were from Florida. Trauma, including blunt trauma of unknown origin, outboard motor propeller wounds, and shooting caused the deaths of 49 (22%) loons, 30 of which were from Minnesota. Diseases, primarily avian botulism type E and aspergillosis, account for 39 (18%) moralities and lead poisoning for 14 (6%), 11 of which had fishing sinkers in their stomachs. Most of the avian botulism type E cases occurred during two outbreaks on Lake Michigan. Seven of the 14 lead-poisoned birds were from Minnesota. Nine (4%) birds died of miscellaneous causes and 9 (4%) of drowning, primarily from entanglement in nets. No diagnosis could be reached for 29 (13%) carcasses. Sample bias precludes interpretation of these data to represent actual proportional causes of mortality in the loon population. However, the sample size is sufficient to clearly identify major causes of mortality.

Minnesota, Florida, Virginia, Michigan, Wisconsin,

Movements of immature bald eagles: Implications for bird aircraft strike hazard

Bald eagle (Haliaeetus leucocephalus) aircraft strikes have increased dramatically over the last 20 years as their populations have recovered to near historic sizes. Their attraction to airfields and their large body size makes them a danger to aircraft and therefore important to airfield wildlife managers. However, their management is complicated by their special protected status and the iconic place they hold in the eyes of the public. To help airfield wildlife managers plan monitoring efforts and make informed management decisions, we studied the movements of 32 bald eagles telemetered as nestlings in the Chesapeake Bay of Virginia, USA. Managers often need to know when fledged eagles are most likely to move enough to encounter airfields near nests. As fledglings aged they moved progressively farther from the nest and spent more time away from the nest. Twenty-eight days after fledging, eagles spent most of the day (81±10%, 95% confidence interval) near the nest (<500 m) and only 7±7% of the daytime away from the nest (>1 km). By day 53 fledglings ventured beyond 2.5 km from the nest and spent 30 ± 15% the day >1 km away from their nest. However, distances moved were influenced by proximity of the nest to water, the quality and salinity of that water, and human population density. Eagles left their natal areas and generally migrated out of the Chesapeake Bay 60.5 ± 7.7 days (4 August) after fledging and returned to the Chesapeake Bay approximately 225 days later (March-April). Eighty-four percent (27 of 32) of the eagles that we tracked encountered 164 airfields across the east coast with 91% of those airfields located within 10 km of the Chesapeake Bay. Encounters with airfields outside the Chesapeake Bay occurred mainly during the first 1.5 years of life, peaking in late fall and early spring. Eagles were recorded on Chesapeake Bay airfields during each year, but encounters peaked in April of the first year of the bird’s life. This month coincides with the height of reported strikes of eagles by aircraft in the region. Our results suggest that eagles fledging from the Chesapeake Bay are not only an issue for airports near the Chesapeake Bay, but for airports across the east coast. Given the continued growth of the population, this issue is likely to continue and grow in significance.

Virginia

Continuous Turbidity Monitoring in the Indian Creek Watershed, Tazewell County, Virginia, 2006-08

Thousands of miles of natural gas pipelines are installed annually in the United States. These pipelines commonly cross streams, rivers, and other water bodies during pipeline construction. A major concern associated with pipelines crossing water bodies is increased sediment loading and the subsequent impact to the ecology of the aquatic system. Several studies have investigated the techniques used to install pipelines across surface-water bodies and their effect on downstream suspended-sediment concentrations. These studies frequently employ the evaluation of suspended-sediment or turbidity data that were collected using discrete sample-collection methods. No studies, however, have evaluated the utility of continuous turbidity monitoring for identifying real-time sediment input and providing a robust dataset for the evaluation of long-term changes in suspended-sediment concentration as it relates to a pipeline crossing. In 2006, the U.S. Geological Survey, in cooperation with East Tennessee Natural Gas and the U.S. Fish and Wildlife Service, began a study to monitor the effects of construction of the Jewell Ridge Lateral natural gas pipeline on turbidity conditions below pipeline crossings of Indian Creek and an unnamed tributary to Indian Creek, in Tazewell County, Virginia. The potential for increased sediment loading to Indian Creek is of major concern for watershed managers because Indian Creek is listed as one of Virginia's Threatened and Endangered Species Waters and contains critical habitat for two freshwater mussel species, purple bean (Villosa perpurpurea) and rough rabbitsfoot (Quadrula cylindrical strigillata). Additionally, Indian Creek contains the last known reproducing population of the tan riffleshell (Epioblasma florentina walkeri). Therefore, the objectives of the U.S. Geological Survey monitoring effort were to (1) develop a continuous turbidity monitoring network that attempted to measure real-time changes in suspended sediment (using turbidity as a surrogate) downstream from the pipeline crossings, and (2) provide continuous turbidity data that enable the development of a real-time turbidity-input warning system and assessment of long-term changes in turbidity conditions. Water-quality conditions were assessed using continuous water-quality monitors deployed upstream and downstream from the pipeline crossings in Indian Creek and the unnamed tributary. These paired upstream and downstream monitors were outfitted with turbidity, pH (for Indian Creek only), specific-conductance, and water-temperature sensors. Water-quality data were collected continuously (every 15 minutes) during three phases of the pipeline construction: pre-construction, during construction, and post-construction. Continuous turbidity data were evaluated at various time steps to determine whether the construction of the pipeline crossings had an effect on downstream suspended-sediment conditions in Indian Creek and the unnamed tributary. These continuous turbidity data were analyzed in real time with the aid of a turbidity-input warning system. A warning occurred when turbidity values downstream from the pipeline were 6 Formazin Nephelometric Units or 15 percent (depending on the observed range) greater than turbidity upstream from the pipeline crossing. Statistical analyses also were performed on monthly and phase-of-construction turbidity data to determine if the pipeline crossing served as a long-term source of sediment. Results of this intensive water-quality monitoring effort indicate that values of turbidity in Indian Creek increased significantly between the upstream and downstream water-quality monitors during the construction of the Jewell Ridge pipeline. The magnitude of the significant turbidity increase, however, was small (less than 2 Formazin Nephelometric Units). Patterns in the continuous turbidity data indicate that the actual pipeline crossing of Indian Creek had little influence of downstream water quality; co

Scientific Investigations Report

Reproductive success and habitat characteristics of Golden-winged Warblers in high-elevation pasturelands

The Golden-winged Warbler ( Vermivora chrysoptera ) is one of the most rapidly declining vertebrate species in the Appalachian Mountains. It is the subject of extensive range-wide research and conservation action. However, little is known about this species' breeding ecology in high-elevation pasturelands, a breeding habitat with conservation potential considering the U.S. Natural Resource Conservation Service's Working Lands for Wildlife program targeting private lands in the Appalachian Mountains. We located 100 nests of Golden-winged Warblers in pastures in and around the Monongahela National Forest in West Virginia during 2008&ndash;2012. Daily nest survival rate (mean &plusmn; SE = 0.962 &plusmn; 0.006), clutch size (4.5 &plusmn; 0.1), and number of young fledged per nest attempt (2.0 &plusmn; 0.2) and successful nest (4.0 &plusmn; 0.1) fell within the range of values reported in other parts of the species' range and were not significantly affected by year or the presence/absence of cattle grazing. Classification tree analysis revealed that nests were in denser vegetation (&ge;52%) and closer to forest edges (<36.0 m) and shrubs (<7.0 cm) than random locations within the male's territory. Successful nests had significantly more woody cover (&ge;9%) within 1 m than failed nests. Our results suggest that cattle grazing at 1.2&ndash;2.4 ha of forage/animal unit with periodic mowing can create and maintain these characteristics without interfering with the nesting of Golden-winged Warblers. High-elevation pasturelands may provide a refuge for remaining populations of Golden-winged Warblers in this region.

Wilson Journal of Ornithology

At-a-Glance—Summary of the 2023 U.S. Geological Survey Cooperative Research Units Program Year-in-Review

Introduction Established in 1935, the U.S. Geological Survey (USGS) Cooperative Fish and Wildlife Research Units (CRU) program is a unique partnership among the USGS, State Fish and Wildlife agencies, host universities, the Wildlife Management Institute (WMI), and the U.S. Fish and Wildlife Service (FWS). As of 2023, there are 43 CRUs in 41 states that fall under three supervisory regions and a National Program Office located at USGS in Reston, Virginia.

Fact Sheet

Woodcock status report, 1960

Singing ground counts for 1960 from 40 routes west of the Appalachians and 166 routes east of this range were available for comparison with counts made on the same routes in 1959. While the measurements of change in the woodcock breeding index between years relate, properly speaking, only to these routes as selected by the cooperators, this is the best information we have on the breeding population of the area east of Wisconsin and north of Tennessee and South Carolina.* East of the Appalachians the sample data indicated a statistically significant decrease of 10 per cent, and it probably is safe to conclude that the true drop did not exceed 19 per cent. West of the Appalachians an average increase of 7 per cent was indicated, and 95 per cent confidence limits suggest- that if a decrease did occur on the sample routes, it probably was not more than 13 per cent. For both areas combined, a decrease of 2 per cent was recorded on the 206 routes sampled, with confidence limits of an increase of 9 per cent or a decrease of 12 per cent. There is no evidence of a disastrous population decrease in spite of the severe weather conditions of March 1960. *No comparative data were available from Indiana, Quebec, Rhode Island, Delaware or Virginia; and only one route in Minnesota and one in Wisconsin were covered both years.

Special Scientific Report - Wildlife

Decision support tools for brown pelican management in the northern Gulf of America (Gulf of Mexico)

Management plans with clear priorities can help to achieve brown pelican Pelecanus occidentalis conservation objectives in the northern Gulf of America (Gulf of Mexico). Efforts to establish clear priorities can be hindered by information gaps, especially those related to the uncertainty associated with changing conditions that influence brown pelican populations. We addressed these gaps by creating a model that uses island-specific conditions (e.g., geomorphology; predator-related conditions; brown pelican terrestrial nesting, roosting, and loafing habitats) to predict the nest count as a proxy for breeding pairs on the island. We used the model and 2000–2015 brown pelican nest count data to estimate if breeding pair targets that we identified or estimated for 10 U.S Fish and Wildlife Service Gulf Coast Biological Planning Units were met while accounting for uncertainty. Our results indicate that breeding pair targets were met in 7 of the 10 units by existing conditions. Our confidence in judging nest deficits tended to decrease from west to east because the model over-predicted total nests in the east Gulf Coast. Using an island from our data, we show how the model could be used to quantify the uncertainty of nest count outcomes under simulated changes in island conditions. The model indicated that the island's existing conditions most probably result in nests (probability = 0.51) and that increasing the area of nesting habitat (shrubs) could increase the probability of nests from 49% to 70%. Increasing shrub habitat in the model also increased nest count uncertainty by 60%, but this was due to a greater probability of larger nest counts. Our model suggests that nest count uncertainty could be reduced by improving data on island size, shrub area, and predator presence, depending on the unit and how isolated the island is from the mainland. These tools could help managers understand and incorporate the uncertainty associated with creating island conditions that are intended to help achieve brown pelican conservation objectives.

Alabama, Florida, Louisiana, Mississippi, Texas

Demographic response of Louisiana Waterthrush, a stream obligate songbird of conservation concern, to shale gas development

Shale gas development continues to outpace the implementation of best management practices for wildlife affected by development. We examined demographic responses of the Louisiana Waterthrush ( Parkesia motacilla ) to shale gas development during 2009–2011 and 2013–2015 in a predominantly forested landscape in West Virginia, USA. Forest cover across the study area decreased from 95% in 2008 to 91% in 2015, while the area affected by shale gas development increased from 0.4% to 3.9%. We quantified nest survival and productivity, a source–sink threshold, riparian habitat quality, territory density, and territory length by monitoring 58.1 km of forested headwater streams ( n = 14 streams). Across years, we saw annual variability in nest survival, with a general declining trend over time. Of 11 a priori models tested to explain nest survival ( n = 280 nests), 4 models that included temporal, habitat, and shale gas covariates were supported, and 2 of these models accounted for most of the variation in daily nest survival rate. After accounting for temporal effects (rainfall, nest age, and time within season), shale gas development had negative effects on nest survival. Population-level nest productivity declined and individual productivity was lower in areas disturbed by shale gas development than in undisturbed areas, and a source–sink threshold suggested that disturbed areas were more at risk of being sink habitat. Riparian habitat quality scores, as measured by a U.S. Environmental Protection Agency index and a waterthrush-specific habitat suitability index, differed by year and were negatively related to the amount of each territory disturbed by shale gas development. Territory density was not related to the amount of shale gas disturbance, but decreased over time as territory lengths increased. Overall, our results suggest a decline in waterthrush site quality as shale gas development increases, despite relatively small site-wide forest loss.

West Virginia

Vulnerabilities to climate change of Massachusetts animal species of greatest conservation need

Over the last decade, the Commonwealth of Massachusetts has addressed the potential and actual impacts of climate change on state flora and fauna. The state’s involvement began in 2007 when, led by the Division of Fisheries and Wildlife (DFW) and assisted by Manomet Center for Con-servation Research, it carried out one of the first habitat vulnerability assessments in North America (Manomet, 2010). The new methods and processes that resulted were later applied to vulnerability assessments in North America and elsewhere. In 2011, the state assisted the North-eastern Association of Fish and Wildlife Agencies (NEAFWA) in organizing and leading a pio-neering three-year, thirteen-state research effort to evaluate the vulnerabilities of fish and wild-life habitats to climate change in the northeast, from Maine south to West Virginia (NEAFWA, 2012). This focus on climate change vulnerabilities led to three important early realizations: (1) simply categorizing and scoring vulnerabilities might not lead to better conservation outcomes. It was vital to also understand why some resources were more or less vulnerable to climate change in order to identify potential intervention points on which conservation actions and strategies could be based. (2) simply producing research results was not enough; these results had to be cast as specific conservation actions. Moreover (3), these actions needed to be communicated in a useful form to conservation “actors”, such as state agencies, land trusts, land managers, etc. These real-izations led to the next step on the Commonwealth’s journey to effective conservation in an age of climate change - the Massachusetts Wildlife Climate Action Tool (CAT).

Report

Allowable take of black vultures in the eastern United States

Black vultures ( Coragyps atratus ) have been increasing in density and expanding their range in the eastern United States since at least the 1960s. In many areas, their densities have increased to the level where they are causing damage to property and livestock and the number of requests for allowable take permits has increased throughout these areas. The United States Fish and Wildlife Service (USFWS) requires updated information to help inform the number of take permits that could reduce conflicts while meeting obligations under the Migratory Bird Treaty Act. We expanded analyses used to estimate allowable take in Virginia to cover the range of black vultures in the eastern United States. We used the prescribed take level approach, which integrates demographic rates, population size estimates, and management objectives into an estimate of allowable take. We provide estimates of allowable take at 4 different scales: individual states, Bird Conservation Regions, USFWS administrative regions, and flyways. Our updated population time series provides evidence of rapidly increasing black vulture populations in many regions of the eastern United States, with an overall population estimate of approximately 4.26 million in 2015 in the Atlantic and Mississippi Flyways. Estimated allowable take ranged from a few hundred individuals per year in states at the northern end of the species range to approximately 287,000/year over the entire eastern United States. The USFWS has no legal mandate regarding the spatial scale at which take should be managed and we found little biological evidence of subpopulation structure for black vultures in the eastern United States. We suggest that allowable take for the species be implemented at a scale that meets stakeholder objectives (e.g., reducing conflict, and ensuring that black vultures are not extirpated from local areas) and is efficient for administrative and monitoring purposes.

Journal of Wildlife Management

Canada geese in the Atlantic Flyway

Large changes have occurred in the geographic wintering distribution and subspecies composition of the Atlantic Flyway population of Canada geese ( Branta canadensis ) over the last 40 years. The Atlantic Flyway can be thought of as being partitioned into four regions: South, Chesapeake, mid-Atlantic, and New England. Wintering numbers have declined in the southern states (North Carolina, South Carolina, Georgia, Florida), increased then decreased in the Chesapeake region (Delaware, Maryland, Virginia), and increased markedly in the mid-Atlantic region (New York, New Jersey, Pennsylvania, West Virginia) (Serie 1993; Fig. 1). In the New England region (Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut), wintering numbers increased from around 6,000 during 1948-50 to between 20,000 and 30,000 today (Serie 1993). Overall, the total number of wintering geese reaching a peak of 955,000 in 1981 and has since declined 40% to 569,000 in 1993. Compounding these distributional changes in wintering numbers, the subspecies composition has also changed. The Canada goose population is composed of migrant geese (primarily B.c. canadensis and B.c. interior ) that breed in the subarctic regions of Canada and resident geese (primarily B.c. maxima and B.c. moffitti ) that breed in southern Canada and the United States (Stotts 1983). The number of resident geese in Maine to Virginia has increased considerable from maybe 50,000 to 100,000 in 1981 (Conover and Chasko 1985) to an average of 560,000 in 1992-93 (H. Heusman, Massachusetts Division of Fisheries and Wildlife, personal communication). This rapid increase in resident geese suggests that the migrant population has declined more than the 40% decline observed in total wintering geese from 1981 to 1993.

Atlantic Flyway

Global climate change and wildlife in North America

It is widely accepted by the scientific community that the earth, which has always experienced climate variation, is now undergoing a period of rapid climate change that is enhanced by anthropogenic atmospheric carbon enrichment during the past 100 years. These climatic changes are accelerating and projections for the next 100 years indicate extensive warming in most (but not all) areas, changing patterns of precipitation, and a significant acceleration of sea level rise. Other likely components of ongoing climate change include changes in season lengths, decreasing range of nighttime versus daytime temperatures, declining snowpack, and increasing frequency and intensity of severe weather events. The many components of climate change, and especially the unprecedented rapid rate of change, are just as important as increasing temperatures. Wildlife species are closely adapted to their environments and readily respond to climate variation. However, as discussed in this technical review, the climate change now underway has extensive potential to affect wildlife throughout North America, either directly or indirectly through responses to changing habitat conditions. When considered in combination with other factors (e.g., pollution, ozone depletion, urbanization, etc.), the potential effect is even greater. The effects of climate change on populations and range distributions of wildlife are expected to be species specific and highly variable, with some effects considered negative and others considered positive. In North America the ranges of habitats and wildlife are predicted to generally move northward as temperatures increase. Variations in this overall pattern will be dependent upon specific local conditions, changing precipitation patterns, and the response of different species to different components of climate change. It follows that the structure of plant–animal communities will also change. Ignoring climate change is likely to increasingly result in failure to reach wildlife management objectives. Wildlife managers need to become knowledgeable about climate change, ways to cope with it, and ways to take advantage of it. Management options currently available include protecting coastal wetlands to allow for sea level rise, reducing the risks to wildlife from potential catastrophic events, adjusting yield and harvest models, accounting for known climatic variations, and taking climate change into consideration when selecting the location and other characteristics of conservation areas. Wildlife managers also need to expect the unexpected and reduce nonclimate stressors on ecosystems. Overall, wildlife managers can minimize negative impacts to wildlife and take advantage of positive aspects by planning ahead and employing adaptive management.

Technical Review