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At least 361 records · Page 20Linked to original sources
USGS2014

Influences of the Tamarisk Leaf Beetle ( Diorhabda carinulata ) on the diet of insectivorous birds along the Dolores River in Southwestern Colorado

We examined the effects of a biologic control agent, the tamarisk leaf beetle (Diorhabda carinulata), on native avifauna in southwestern Colorado, specifically, addressing whether and to what degree birds eat tamarisk leaf beetles. In 2010, we documented avian foraging behavior, characterized the arthropod community, sampled bird diets, and undertook an experiment to determine whether tamarisk leaf beetles are palatable to birds. We observed that tamarisk leaf beetles compose 24.0 percent (95-percent-confidence interval, 19.9-27.4 percent) and 35.4 percent (95-percent-confidence interval, 32.4-45.1 percent) of arthropod abundance and biomass in the study area, respectively. Birds ate few tamarisk leaf beetles, despite a superabundance of D. carinulata in the environment. The frequency of occurrence of tamarisk leaf beetles in bird diets was 2.1 percent (95-percent-confidence interval, 1.3- 2.9 percent) by abundance and 3.4 percent (95-percent-confidence interval, 2.6-4.2 percent) by biomass. Thus, tamarisk leaf beetles probably do not contribute significantly to the diets of birds in areas where biologic control of tamarisk is being applied.

Colorado;Utah↗
USGS2016

Identifying bird and reptile vulnerabilities to climate change in the southwestern United States

Current and future breeding ranges of 15 bird and 16 reptile species were modeled in the Southwestern United States. Rather than taking a broad-scale, vulnerability-assessment approach, we created a species distribution model (SDM) for each focal species incorporating climatic, landscape, and plant variables. Baseline climate (1940–2009) was characterized with Parameter-elevation Regressions on Independent Slopes Model (PRISM) data and future climate with global-circulation-model data under an A1B emission scenario. Climatic variables included monthly and seasonal temperature and precipitation; landscape variables included terrain ruggedness, soil type, and insolation; and plant variables included trees and shrubs commonly associated with a focal species. Not all species-distribution models contained a plant, but if they did, we included a built-in annual migration rate for more accurate plant-range projections in 2039 or 2099. We conducted a group meta-analysis to (1) determine how influential each variable class was when averaged across all species distribution models (birds or reptiles), and (2) identify the correlation among contemporary (2009) habitat fragmentation and biological attributes and future range projections (2039 or 2099). Projected changes in bird and reptile ranges varied widely among species, with one-third of the ranges predicted to expand and two-thirds predicted to contract. A group meta-analysis indicated that climatic variables were the most influential variable class when averaged across all models for both groups, followed by landscape and plant variables (birds), or plant and landscape variables (reptiles), respectively. The second part of the meta-analysis indicated that numerous contemporary habitat-fragmentation (for example, patch isolation) and biological-attribute (for example, clutch size, longevity) variables were significantly correlated with the magnitude of projected range changes for birds and reptiles. Patch isolation was a significant trans-specific driver of projected bird and reptile ranges, suggesting that strategic actions should focus on restoration and enhancement of habitat at local and regional scales to promote landscape connectivity and conservation of core areas.

Open-File Report↗
USGS2018

Monitoring breeding and migration of neotropical migratory birds at Naval Base Coronado, Remote Training Site, Warner Springs, San Diego County, California, 5-year summary, 2013–17

We operated a bird banding station on the Naval Base Coronado, Remote Training Site, Warner Springs (RTSWS), in northeastern San Diego County, California, during the bird breeding season (spring/summer) from 2013 to 2017 and during migration (fall) from 2013 to 2016. The station was established in spring 2013 as part of the Monitoring Avian Productivity and Survivorship (MAPS) program and continued into the fall for the first 4 years as part of a long-term monitoring program for neotropical migratory birds. We captured 705 individuals of 58 species during the MAPS/breeding season from 2013 to 2017 (12–13 days each year in April through August), 79 percent of which were newly banded during the MAPS season (555), 8 percent of which were recaptures banded in previous years (57), and 13 percent of which we released unbanded (64 hummingbirds and 29 other birds that were released or escaped prior to banding). Sixty individuals were captured more than once within a year during MAPS. Bird capture rate averaged 19 ± 1 captures per 100 net-hours (range 17–20) across 5 years. Annual species richness ranged from 28 (2017) to 42 (2014). The average species richness per day was highest in 2014 (9 ± 3) and lowest in 2016 (6 ± 2). Bushtit ( Psaltriparus minimus ) was the most abundant breeding species captured, followed by Spotted Towhee ( Pipilo maculatus ), Oak Titmouse ( Baeolophus inornatus ), Anna’s Hummingbird ( Calypte anna ), House Wren ( Troglodytes aedon ), Ash-throated Flycatcher ( Myiarchus cinerascens ), California Scrub-jay ( Aphelocoma californica ), Bewick’s Wren ( Thryomanes bewickii ), Acorn Woodpecker ( Melanerpes formicivorus ), California Towhee ( Melozone crissalis ), and Western Bluebird ( Sialia mexicana ). Each of these 11 breeding species accounted for at least 5 percent of captures in any 1 year. Fifty-seven percent of known-sex captures were female and 43 percent were male. Thirty-three percent of known-age captures were juveniles. Peaks in number of birds captured were in the first and last weeks of April, and the greatest number of species was captured in early May.

California↗
USGS2021

Structured decision making and optimal bird monitoring in the northern Gulf of Mexico

The avian conservation community struggles to design and implement large scale, long-term coordinated bird monitoring programs within the northern Gulf of Mexico due to the complexity of the conservation enterprise in the region; this complexity arises from the diverse stakeholders, multiple jurisdictions, complex ecological processes, myriad habitats, and over 500 species of birds using the region for at least some part of their annual cycle. In addition, long-term monitoring over large spatial scales is difficult because of the need for monitoring data to both (1) evaluate management and restoration outcomes, and (2) provide reliable information about the status and trends of bird populations over time. To address these challenges, the Gulf of Mexico Avian Monitoring Network developed a problem statement: “How can a cost-effective monitoring strategy for the Gulf Coast bird community and ecosystem be developed that evaluates ongoing conservation activities and chronic and acute threats; maximizes learning; and is flexible and holistic enough to detect novel ecological threats and evaluate new and emerging conservation activities?” A structured decision-making framework was then used to articulate and quantify stakeholder values related to the problem statement. One use of the stakeholder values was to develop a regional, strategic plan for bird monitoring, which is presented elsewhere. A formal and complete decision support tool for conservation investments in monitoring and research guided by the stakeholder values is presented in this report. The technical aspects of the stakeholder value model and a portfolio analysis that could be used to guide decision making when allocating resources for monitoring activities is described. Whereas the decision analysis presented here could be useful to any decision maker faced with difficult choices about resource allocation, it is designed for decision makers who request monitoring study proposals and then determine which combination of proposals to fund. The portfolio decision support tool is designed to help funding agencies and organizations identify resource allocation strategies to maximize stated objectives. To begin the decision analysis, an objectives hierarchy and quantitative performance metrics from the values of the Gulf of Mexico bird conservation community were created by a panel of regional stakeholders. Each fundamental objective and sub-objective in the hierarchy is composed of several performance metrics. To test the decision support tool, the authors evaluated a combination of monitoring study proposals written for the region and simulated proposals. Each proposal was scored against the performance metrics and used multi-attribute utility theory to combine the multiple objectives into a measure of total monitoring benefit. The total monitoring benefit and costs of each proposal were then used in a constrained optimization routine to identify optimal monitoring portfolios, that is, a combination of activities that maximizes monitoring benefits while meeting cost and other constraints of interest to stakeholders. A graphical solution based on the concept of Pareto efficiency, which is useful in situations when cost constraints and exact budgets are not known, is also provided. Finally, an evaluation of the sensitivity of the decision-making framework to the weights assigned to objectives by stakeholders is included. This decision support tool allows decision makers to identify an optimal suite of monitoring proposals with a transparent portfolio analysis that includes user-defined constraints (such as costs).

Alabama, Florida, Louisiana, Mississippi, Texas↗
USGS2024

Viral pathogen detection in U.S. game-farm mallard (Anas platyrhynchos) flags spillover risk to wild birds

The threat posed by emerging infectious diseases is a major concern for global public health, animal health and food security, and the role of birds in transmission is increasingly under scrutiny. Each year, millions of mass-reared game-farm birds are released into the wild, presenting a unique and a poorly understood risk to wild and susceptible bird populations, and to human health. In particular, the shedding of enteric pathogens through excrement into bodies of water at shared migratory stop-over sites, and breeding and wintering grounds, could facilitate multi-species long-distance pathogen dispersal and infection of high numbers of naive endemic birds annually. The Mallard ( Anas platyrhynchos ) is the most abundant of all duck species, migratory across much of its range, and an important game species for pen-rearing and release. Major recent population declines along the US Atlantic coast has been attributed to game-farm and wild mallard interbreeding and the introduction maladaptive traits into wild populations. However, pathogen transmission and zoonosis among game-farms Mallard may also impact these populations, as well as wildlife and human health. Here, we screened 16 game-farm Mallard from Wisconsin, United States, for enteric viral pathogens using metatranscriptomic data. Four families of viral pathogens were identified – Picobirnaviridae (Genogroup I), Caliciviridae (Duck Nacovirus ), Picornaviridae (Duck Aalivirus ) and Sedoreoviridae (Duck Rotavirus G). To our knowledge, this is the first report of Aalivirus in the Americas, and the first report of Calicivirus outside domestic chicken and turkey flocks in the United States. Our findings highlight the risk of viral pathogen spillover from peri-domestically reared game birds to naive wild bird populations.

Frontiers Earth Science Journal↗
USGS2008

Responses in bird communities to wildland fires in southern California

There is a growing body of literature covering the responses of bird species to wildland fire events. Our study was unique among these because we investigated the effects of large-scale wildland fires on entire bird communities across multiple vegetation types. We conducted avian point counts during the breeding seasons for two years before and two years after the Cedar and Otay Fires in 2003 in southern California. Our balanced sampling effort took place at two sites, one low-elevation and one high-elevation, each containing replicate stations (burned and unburned) within five vegetation types: chaparral, coastal sage scrub, grassland, oak woodland, and riparian. Although fire caused some degree of change in the vegetation structure at all of our impacted survey points, we found that the post-fire shrub and tree cover was significantly lower in only two of the vegetation types within the low-elevation site, coastal sage scrub and chaparral. We found no significant changes in cover at the high-elevation site. Using univariate and multivariate analyses, we tested whether the fires were associated with a change in bird species diversity, community structure, and the relative abundance of individuals within a species. We found that species diversity changed in only one circumstance: it increased in coastal sage scrub at the low-elevation site. Multivariate analyses revealed significant differences in the post-fire bird community structure in the low-elevation chaparral, low-elevation coastal sage scrub, and the high-elevation grassland communities. Vegetation characteristics altered by fire, such as decreases in shrub and tree cover, influenced the changes we observed in the bird communities. The relative abundance of some species (lazuli bunting [ Passerina amoena ] and horned lark [ Eremophila alpestris ]) significantly increased after the fires, while other species declined significantly (Anna's hummingbird [ Calypte anna ], wrentit [ Chamaea fasciata ], and bushtit [ Psaltriparus minimus ]). We detected mixed results for the spotted towhee ( Pipilo maculatus ), which increased in burned chaparral and declined in burned coastal sage scrub within the low-elevation site. We suggest that the observed responses of birds to these fires may be attributed to: (1) the availability of nearby unburned refugia, (2) the continued suitability of post-fire vegetation at the study sites, and (3) the generally high mobility of this taxon.

California↗
USGS2018

Patch and landscape responses of bird abundance to fragmentation in agroecosystems of east-central Argentina

Forest fragmentation in agroecosystems is linked to declines of avian species worldwide. Agriculture has greatly reduced native forest cover in east-central Argentina. Assessing the influence of fragmentation on forest bird populations is vital to inform reliable conservation and management strategies for the Espinal region of Argentina. We determined the relationships of vegetation structure within native forest patches, size and shape of these patches (patch scale), composition and spatial configuration (at landscape scale) to relative abundance of 17 forest bird species during austral fall-winter and spring-summer seasons. Birds were sampled from 2007 – 2009 in 45 forest patches within three landscape mosaics (30x30 km) representing a gradient of native forest fragmentation in east-central Argentina. We used an information-theoretic approach and approximated model inference to examine the effect of predictor environmental variables at two spatial scales on patterns of forest bird abundance. Density of trees within forest patches was the main predictor of bird abundance at the patch scale. Amount of forest and spatial configuration were also important. The abundance of several bird species was greater in patches with high density of trees and landscapes characterized by more forest cover and larger patches in close proximity. We found two main avian response patterns to forest fragmentation and patch characteristics. This information contributes reliable knowledge for the design of conservation measures of agricultural landscapes in the Espinal region of Argentina.

Avian Conservation and Ecology↗
USGS2018

Chlamydia psittaci in feral Rosy-faced Lovebirds (Agapornis roseicollis) and other backyard birds in Maricopa County, Arizona

In 2013, a mortality event of nonnative, feral Rosy-faced Lovebirds ( Agapornis roseicollis ) in residential backyards in Maricopa County, Arizona, US was attributed to infection with Chlamydia psittaci . In June 2014, additional mortality occurred in the same region. Accordingly, in August 2014 we sampled live lovebirds and sympatric bird species visiting backyard bird feeders to determine the prevalence of DNA and the seroprevalence of antibodies to C. psittaci using real-time PCR-based testing and elementary body agglutination, respectively. Chlamydia psittaci DNA was present in conjunctival-choanal or cloacal swabs in 93% (43/46) of lovebirds and 10% (14/142) of sympatric birds. Antibodies to C. psittaci were detected in 76% (31/41) of lovebirds and 7% (7/102) of sympatric birds. Among the sympatric birds, Rock Doves ( Columba livia ) had the highest prevalence of C. psittaci DNA (75%; 6/8) and seroprevalence (25%; 2/8). Psittacine circovirus 1 DNA was also identified, using real-time PCR-based testing, from the same swab samples in 69% (11/16) of species sampled, with a prevalence of 80% (37/46) in lovebirds and 27% (38/142) in sympatric species. The presence of either Rosy-faced Lovebirds or Rock Doves at residential bird feeders may be cause for concern for epizootic and zoonotic transmission of C. psittaci in this region.

Arizona↗
USGS2025

Observational, virological, and serological data provide insights into an outbreak of highly pathogenic avian influenza among wild birds on the Yukon-Kuskokwim Delta, Alaska in 2022

In 2021–22, clade 2.3.4.4b highly pathogenic avian influenza (HPAI) viruses were introduced by wild birds into North America, leading to geographically widespread disease. In response to HPAI outbreaks throughout late 2021 and early 2022, we recorded observations of sick and dead birds, estimated abundance of carcasses, collected swab and sera samples to detect viruses, and monitored bird nesting on the Yukon-Kuskokwim Delta region of Alaska to document potential effects of disease. Thirty-six reports of sick and dead birds were registered across the region. Nineteen carcasses were opportunistically collected for diagnostic testing, of which 12 were confirmed to be infected with clade 2.3.4.4b HPAI viruses. Carcass abundance estimates from line-distance sampling provided evidence that the most common species of dead birds from the western Yukon-Kuskokwim Delta region were Cackling Goose ( Branta hutchinsii minima ), Glaucous Gull ( Larus hyperboreus ), and Black Brant ( Branta bernicla nigricans ). Only one paired cloacal and oropharyngeal swab sample from a Northern Pintail ( Anas acuta ) tested positive for clade 2.3.4.4b HPAI virus, out of 464 live-captured duck and goose samples. Of 195 sera samples from waterfowl screened for antibodies reactive to influenza A viruses, antibodies were found in 41–98% of samples collected from Emperor Goose ( Anser canagicus ), Cackling Goose, Black Brant, and Spectacled Eider ( Somateria fischeri ). In addition, 15–98% of the same sera samples were reactive to a clade 2.3.4.4b H5 antigen. Fewer Black Brant and Emperor Goose nests were found on long-term study plots during 2022 than in previous years. Collectively, we found that HPAI viruses affected at least seven species of wild birds inhabiting the region during 2022. The full scope of impacts of HPAI at this location during 2022 is unknown, but our data indicate that acute effects to avian population health on the Yukon-Kuskokwim Delta region were likely modest.

Alaska↗
USGS1982

Effects of soils and grazing on breeding birds of uncultivated upland grasslands of the Northern Great Plains

The principal use of uncultivated upland grasslands in the northern Great Plains is for livestock production. However, on lands set aside for wildlife or for scientific or recreational use, grazing by livestock may be used as a management measure to enhance populations of game species or to create conditions that increase the diversity of plant or animal species. To determine the effects of grazing on the avifauna of various types of Great Plains grasslands, we conducted bird censuses and plant surveys during 1974-78 on 615 plots of lightly, moderately, or heavily grazed native rangeland.Numbers of horned lark (Eremophila alpestris), western meadowlark (Sturnella neglecta), lark bunting (Calamospiza melanocorys), and chestnut-collared longspur (Calcarius ornatus) accounted for 65-75% of the total bird population, regardless of grazing intensity. For the entire area sampled (600,000 km2), horned lark, western meadowlark, and chestnut-collared longspur were the dominant birds. Major differences in composition of the dominant species and species richness occurred among the major soils. Increased mean annual soil temperature seemingly had a greater negative influence on avian species richness than did decreased soil moisture or organic matter content. Differences in total bird density were not significant among soils and among grazing intensities within most soils. For the area as a whole, light or moderate grazing resulted in increased species richness. Of the 29 species studied, 2 responded significantly to grazing for the area as a whole and 6 others to grazing on the soil in which peak densities occurred. Response of several other species to grazing effects evidently varied among strata.A list of plants with mean cover values of more than 1% in any of the 18 combinations of soils and grazing intensities contained less than 25 species, attesting to the relative simplicity of the grassland vegetation in the northern Great Plains. Agropyron spp. and Bouteloua gracilis were the dominant plants that provided greater than average cover on the best habitat for the most bird species. Optimum habitat for each bird species is given in terms of grazing, soils, and dominant plant species. Increased soil temperature probably had a negative effect on plant species richness, especially among soils with a high organic matter content that supported perennial grasses and other mesophytes.

Wildlife Research Report↗
USGS1995

Breeding bird survey: Population trends 1966-92

The North American Breeding Bird Survey (BBS) was begun in 1966 to collect standardized data on bird populations along more than 3,400 survey routes across the continental United States and southern Canada. The BBS has been used to document distributions and establish continental, regional, and local population trends for more than 250 species. We summarize here survey-wide patterns in the 1966-92 population trend estimates for 245 species of birds observed on a minimum of 40 routes with a mean relative abundance of 1.0 bird per route. Survey-wide trend estimates are also summarized for six groupings of birds, providing insight into broad geographical patterns of population trends of North American birds.

Book chapter↗
USGS1995

Population trends from the North American Breeding Bird Survey

INTRODUCTION: Most Neotropical migrant birds are difficult to count accurately and are moderately common over large breeding distributions. Consequently, little historical information exists on their large-scale population changes, and most of this information is anecdotal. Surveys begun in this century such as Breeding Bird Censuses and Christmas Bird Counts have the potential to provide this information, but only the North American Breeding Bird Survey (BBS) achieves the extensive continental coverage necessary to document population changes for most Neotropical migrant birds. Conservationists and ecologists have begun to use BBS data to estimate population trends, but there is still widespread confusion over exactly what these data show regarding population changes. In this chapter, we review the current state of knowledge regarding population changes in Neotropical migrant birds and the methods used to analyze these changes. The primary emphasis is on the BBS (Robbins et al. 1986) because this survey provides the best available data for estimating trends of Neotropical migrants on a continental scale. To address questions about methods of analyzing survey data, we review and compare some alternative methods of analyzing BBS data. We also discuss the effectiveness of the BBS in sampling Neotropical migrant species, and review possibilities for use of alternative data sets to verify trends from the BBS.

Book chapter↗
USGS2000

DC birdscape: a program for monitoring neotropical migrant birds in Washington, DC

Urban and suburban habitats often contain a variety of Neotropical migratory birds, but are poorly sampled by programs such as the North American Breeding Bird Survey. DC Birdscape was developed to inventory and monitor birds in Washington, D.C. Birds were surveyed using a systematic sample of point counts during 1993-1995. Results indicate that species richness of Neotropical migratory birds varied among land-use categories, and that maximum species richness occurred in parkland habitats. Although DC Birdscape has provided relevant information on bird distribution and species richness, it is unclear whether the information is of sufficient management interest to support its continuation as a long-term monitoring program.

Book chapter↗
USGS1980

[Book review] Endangered Birds: Management techniques for preserving threatened species

This volume contains the proceedings of a symposium held at the University of Wisconsin-Madison, during 17-20 August 1977. In the words of the book's editor, Stanley Temple, the symposium "offered a unique opportunity for leading scientists from around the world to meet and share their experiences with endangered birds." That this objective was achieved is indicated by a list of contributors standing as a "Who's Who" in endangered species research and management. This symposium was jointly sponsored by the International Council for Bird Preservation, World Wildlife Fund, National Audubon Society, New York Zoological Society, and U.S. Fish and Wildlife Service. Fifty-one papers by 53 contributors are listed under 10 topics: endangered bird problems and the concept of managing threatened species; increasing reproductive effort and success by reducing nest-site limitations; alleviating problems of competition, predation, parasitism, and disease; supplemental feeding and manipulation of feeding ecology; manipulating aspects of nesting biology; captive breeding of endangered birds; genetic aspects of managing dwindling populations; reintroducing endangered birds to the wild; integrated approaches to management of endangered birds; and summary. A 14-page index provides convenient reference to subjects in the text.

The Auk↗
USGS1989

Habitat area requirements of breeding forest birds of the middle Atlantic states

Conservation of birds requires an understanding of their nesting requirements, including area as well as structural characteristics of the habitat. Previous studies have shown that many neotropical migrant bird species seem to depend on extensive forested areas, but the specific area requirements of individual species have not been clarified sufficiently to aid in design and management of effective preserves. For this 5-year study, bird and vegetation data were obtained at 469 points in forests ranging in area from 0.1 ha to more than 3,000 ha in Maryland and adjacent states. Data were analyzed first by stepwise regression to identify habitat factors that had the greatest influence on relative abundance of each bird species. In the relatively undisturbed mature forests studied, degree of isolation and area were significant predictors of relative abundance for more bird species than were any habitat variables. For species for which forest area was a significant predictor of abundance, we used logistic regression to examine the relationship between forest area and the probability of detecting the species. In managing forest lands for wildlife, top priority should go toward providing for the needs of area-sensitive or rare species rather than increasing species diversity per se. Avian species that occur in small and disturbed forests are generalists that are adapted to survival under edge conditions and need no special assistance from man. Forest reserves with thousands of hectares are required to have the highest probability of providing for the least common species of forest birds in a region. However, if preservation of large contiguous forest tracts is not a realistic option, results of this study suggest 2 alternative approaches. First, if other habitat attributes also are considered, smaller forests may provide suitable breeding sites for relatively rare species. Second, smaller tracts in close proximity to other forests may serve to attract or retain area-sensitive species.

Book↗
USGS1979

Human related mortality of birds in the United States

Modern man serves as both a direct and an indirect cause of the death of birds. In the early 1970's, human activity was responsible for the death of approximately 196 million birds per year, or about 1.9% of the wild birds of the continental United States that died each year. Hunting was the largest direct mortality factor and accounted for about 61% of human related bird deaths. Control or prevention of avian depredations took about 1% of the total, and all research and propagation about 0.5%. Collision with man-made objects was the greatest indirect human cause of avian deaths. accounting for about 32% of the human related deaths. Pollution and poisoning caused the death of about 2% of the total. A relatively few species account for most of this mortality but continue to maintain large, harvestable populations, suggesting that the numbers of most bird species are essentially unaffected by the human activities discussed. Other activities of man that do not necessarily result in the death of birds but rather reduce reproductive potential are more likely to have long-term effects on avian populations.

Special Scientific Report - Wildlife↗
USGS1973

Birds imported into the United States in 1971

Birds imported into the United States in 1971 are tabulated by species. Total numbers for the period 1968-1971 are given for the more commonly imported taxa. The number of birds imported in 1971 increased only slightly over that for.1970. In 1971, 750 species were imported, of which 194 had not been imported in the previous 3 years; since 1968, approximately 1,445 species have been imported. Parrots accounted for nearly 25 percent of all birds imported in 1971, compared to only 13.5 percent in 1970. Birds were imported from 63 foreign countries, but more than 90 percent of all birds came from only 10 countries. The proportion of imported birds presumed to have been raised in captivity decreased in 1971.

Special Scientific Report - Wildlife↗
USGS2011

Greater sage-grouse as an umbrella species for shrubland passerine birds: a multiscale assessment

Working groups and government agen-cies are planning and conducting land actions in sagebrush (Artemisia spp.) habitats to benefit Greater Sage-Grouse (Centrocercus urophasianus) populations. Managers have adopted an umbrella concept, creating habitat characteristics specific to sage-grouse requirements, in the belief that other wildlife species dependent on sagebrush will benefit. We tested the efficacy of this approach by first identifying the primary environmental gradients underlying sagebrush steppe bird com-munities (including Greater Sage-Grouse). We integrated field sampling for birds and vegetation with geographic information system (GIS) data to characterize 305 sites sampled throughout the current range of Greater Sage-Grouse in the Intermountain West, United States. The primary environmental axis defining the bird community represented a gradient from local-scale Wyoming/basin big sagebrush (A. t. ssp. wyomingensis/A. t. ssp. tridentata), and bare ground cover to local and regional grassland cover; the second axis repre-sented a transition from low-elevation Wyoming/basin big sagebrush and bare ground to mountain big sagebrush (A. t. ssp. vaseyana) and habitat edge. We identified the relative overlap of sage-grouse with 13 species of passerine birds along the multiscale gradients and estimated the width of the umbrella when applying management guidelines specific to sage-grouse. Passerine birds associated with sagebrush steppe habitats had high levels of overlap with Greater Sage-Grouse along the multiscale environmental gradients. However, the overlap of the umbrella was prima-rily a function of the broad range of sagebrush habitats used by sage-grouse. Management that focuses on creating a narrow set of plot-scale con-ditions will likely be less effective than restoration efforts that recognize landscape scale heterogene-ity and multiscale organization of habitats. These multiscale efforts may improve some sage-grouse habitats and strengthen the management umb-rella for shrub steppe passerine birds.

Book chapter↗