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At least 1,117 records · Page 62Linked to original sources
USGS1989

Populations, productivity, and feeding habits of seabirds at Cape Thompson, Alaska: Final report

Investigations of seabird population sizes and breeding biology were conducted at Cape Thompson from 1959 to 1961 during pre-development studies associated with the Atomic through 1982, the Alaskan Program (OCSEAP) supported determine whether changes Energy Commission’s “Project Chariot.” From 1976 Outer Continental Shelf Environmental Assessment efforts to recensus seabirds at Cape Thompson and had occurred since the 1959-61 period. Prior to the present study, it had been 6 years since the last efforts to census seabird colonies in this area. We established a field camp at the and occupied it continuously until 31 were selected for cliff nesting species comprising the Cape Thompson complex, mouth of Ikijaktusak Creek on 2 July August 1988. Permanent study plots in four of the five discrete colonies and regular observations were made throughout the study to document attendance patterns, breeding phenology, and success of murres and kittiwakes. Periodic collections of adults offshore were used to determine the food habits of study species. Shore-based work was supplemented with offshore studies of seabird foraging from the USFWS vessel Eagle-Tiglax, 24-31 August (Fig. 2). Correlation analysis revealed negative trends in murre attendance at all Cape Thompson colonies between 1960 and 1982 or 1988, significantly so for 3 of the 5 colonies. Based on apparent changes in species composition within the colonies, Common Murres declined at a more rapid rate than Thick-billed Murres between 1960 and 1988. Combining information from all colonies, it appears that murre populations have been relatively stable since about 1979. In contrast to murres, the kittiwake population showed no significant trends between 1960 and 1982 or between 1960 and 1988. All fluctuations in kittiwake numbers documented between years were within the variability expected within years. Breeding productivity of murres was about average during 1988 (0.47 young/pair), whereas the productivity of kittiwakes was very poor (0.15 young/pair). Murres and kittiwakes fed mostly on arctic cod and sand lance distributed widely but in low concentrations (e.g., 0.1-10 g/m 3 ) UP to 1.20 km north and northwest of Cape Thompson. In the total area surveyed (225 km 2 ), only two major feeding aggregations were observed where fish school densities exceeded 15 g/ins. Forage fish densities were higher in shallow Alaska Coastal Current waters than offshore in Bering Sea waters, and piscivorous seabirds like murres and kittiwakes fed mostly in coastal waters. Reduced numbers of fish in murre and kittiwake stomachs in August and low breeding success of kittiwakes suggested that forage fish densities observed around Cape Thompson in late August were sufficient to sustain murres but were insufficient for, or inaccessible to, kittiwakes. The breeding failure of Black-legged Kittiwakes at Cape Thompson in 1988 was part throughout causes of kittiwakes of a pervasive syndrome of failure in this species observed the Bering/Chukchi seas and Gulf of Alaska in recent years. The recurrent widespread breeding failure need to be identified if are to have a role in area-wide population monitoring during the period of Alaskan OCS development by the oil and gas industry. The system of land-based plots established in 1988 is recommended for future population monitoring of cliff-nesting birds at Cape Thompson. Based on the coefficients of variation among counts observed in this study, it is estimated that 10 replicate counts per year would detect an 8% change in numbers of Thick-billed Murres between years and a 12% change in Common Murres, with 75% certainty of statistical significance at the 0.05 level. Similarly, a 9% annual change in the population of Black-legged Kittiwakes should be detectable at the 0.05 significance level given samples of 10 replicate counts of the land-based plots.

Alaska↗
USGS2010

Comparative morphology among northern populations of breeding Cooper's Hawks

Few studies at a broad geographical scale have characterized intraspecific variation in morphology of woodland hawks in the genus Accipiter . From 1999 to 2007 we investigated morphological variation in large samples of live Cooper's Hawks ( A. cooperii ) nesting in four study areas: coniferous woodland around Victoria, British Columbia, Canada, isolated deciduous woodlands in short-grass prairies of northwestern North Dakota, towns and rural deciduous woodlands along the border of North Dakota and Minnesota, and urban and rural mixed deciduous and coniferous landscapes of Wisconsin. These sites span 2660 km across the northern part of the species' breeding range. We measured body mass (i.e., size), wing chord, tail length, tarsus diameter, hallux length, and culmen length of breeding adults, finding significant and clinal variation in body mass (or size). The smallest and most similar-sized birds occurred in British Columbia and western North Dakota, larger birds along the border between North Dakota and Minnesota, and the largest birds in Wisconsin. Several other characters varied significantly when mass was used as a covariate. Variation by study site in mean indices of sexual size dimorphism was negligible and not significant. We speculate that the morphological differences we found, in part, are the result of geographic isolation, where diets, migratory behavior, and structural characteristics of nesting habitats vary across landscape types.

British Columbia, Minnesota, North Dakota, Wiscons↗
USGS2026

Bird predation obscures detection of acoustic telemetry tags in fish

Increasing application of acoustic telemetry for determining survival, migration and habitat use of fishes highlights the need to improve interpretation of tracks that end abruptly: when is fishing mortality, predation, or some other cause to be inferred? Significant technological advances have led to the development of tags that “sense” predation and can be used to infer information about the type of predator that consumed the tagged fish. However, growing evidence suggests that bird predation is not effectively quantified by the technology. We hypothesized that reduction in sound transmission from acoustic tags in the gut of a bird combined with short bird diving intervals would eliminate detections of acoustic telemetry tags from the surface and severely reduce detection efficiency at depth. We test this hypothesis indirectly with two experiments using cormorant carcasses containing tagged fish in which carcasses were either tethered to a mooring for several hours or lowered through the water to simulate diving behavior. Detection of tagged prey fish in the gut of bird carcasses was severely reduced or negated completely, supporting our hypothesis. By comparison, as expected, tagged fish that were not in the gut of bird carcasses were detected at a higher frequency. Depth and distance to passive moored receivers also affected detection probability of tagged fish with more detections at depth and when closer to the receiver. Our results emphasized the importance of accounting for avian predation of tagged fish in studies of prey species in surface waters. Further, while recent development of predation sensing tags has illustrated a few examples of bird predation, our results demonstrate that determining that a tagged fish has been consumed by a diving bird will be difficult and will likely require alternative methods or technologies.

Animal Biotelemetry↗
USGS2009

Short- and long-term implications of clearcut and two-age silviculture for conservation of breeding forest birds in the central Appalachians, USA

Two-age (deferment or leave tree) harvesting is used increasingly in even-aged forest management, but long-term responses of breeding avifauna to retention of residual canopy trees have not been investigated. Breeding bird surveys completed in 1994-1996 in two-age and clearcut harvests in the central Appalachian Mountains of West Virginia, USA allowed us to document long-term changes in these stands. In 2005 and 2006, we conducted point counts in mature unharvested forest stands and in 19-26 year-old clearcut and two-age harvests from the original study and in younger clearcut and two-age stands (6-10 years old). We found differences in breeding bird metrics among these five treatments and temporal differences in the original stands. Although early-successional species are typically absent from group selection cuts, they were almost as common in young two-age stands as clearcuts, supporting two-age harvests as an alternative to clearcutting. Although older harvests had lower species richness and diversity, they were beginning to provide habitat for some species of late-successional forest songbirds that were absent or uncommon in young harvests. Overall, late-successional forest-interior species were more flexible in their use of different seral stages; several species used both age classes and harvest types in addition to mature forest, which may reflect the lack of edges in our heavily-forested landscape. Consequently, two-age management provides habitat for a diverse group of species as these stands mature and may be an ecologically sustainable alternative to clearcutting in landscapes where brown-headed cowbirds (Molothrus ater) are uncommon. ?? 2008 Elsevier Ltd.

Biological Conservation↗
USGS2000

Application of a modified harness design for attachment of radio transmitters to shorebirds

Radio transmitter attachment methodology is important to the design of radio telemetry studies. In 1998, we attached 5 transmitters to a captive population of Western Sandpipers ( Calidris mauri ) and 7 transmitters to wild Killdeer ( Charadriusv ociferus ) using a modified version of the Rappole and Tipton (1991) figure-8 leg-loop harness. Captive birds fitted with harnesses did not exhibit quantifiable differences in behavior relative to control birds. Based on initial success in using the leg-loop harnesses, we used harnesses to attach transmitters in the wild to 30 Killdeer and 49 Dunlin ( Calidris alpina ) during the winters of 1998-1999 and 1999-2000. This was part of a study on movements of wintering shorebirds in the Willamette Valley of Oregon, USA. Wild birds showed no adverse effects of the harnesses.Thus, the described harness is a practical method for attachment of transmitters to shorebirds. Advantages of this harness method include a reduction in handling time at capture, elimination of the need to clip feathers for attachment, and increased transmitter retention time.

Oregon↗
USGS1999

Le Conte's sparrows breeding in Conservation Reserve Program fields: precipitation and patterns of population change

The climate of the North American Great Plains is highly dynamic, with great year-to-year variability in precipitation and periodic, often extreme, wet and dry cycles (Bragg 1995). Drought is a major force of ecological disturbance on the Great Plains and has played a key role in directing the evolution of the grassland biota of this region (Knopf and Samson 1997). Although grassland birds may differ in their responses to enviromenental variations (Rotenberry and Wiens 1991), climatic variability and concomitant unpredictability of resources strongly influence populations of grassland birds across space and time (Wiens 1974, 1986; Cody 1985). Not surprisingly, breeding bird populations on the Great Plains are highly dynamic, exhibiting considerable annual variation in composition, abundance, and distribution (Johnson and Grier 1988, George et al. 1992, Zimmerman 1992, Igl and Johnson 1997). Recently, interest in grassland birds has increased with the recognition that many species are declining both continentally (Droege and Sauer 1994) and globally (Goriup 1988). Identification of the specific factors associated with grassland bird declines in North America, however, remains largely enigmatic (Herkert 1997), and it is complicated by the considerable annual fluctuations in grassland bird distribution and abundance (Igl and Johnson 1997). Although there is evidence that land-use changes on the breeding grounds may have contributed to grassland bird declines (e.g., Igl and Johnson 1997), there also is an indication that long-term drought conditions may have influenced recent population changes of some breeding birds on the Great Plains (Droege and Sauer 1989, Peterjohn and Sauer 1993, Bethke and Nudds 1995, Igl and Johnson 1997). Le Conte's Sparrow (Ammodramus leconteii) is a secretive grassland bird that breeds in central and southern Canada and the northcentral United States (Murray 1969). It winters primarily in the southern United States (Peterson 1980, 1990). Like populations of many grassland breeding birds in North America (Fretwell 1986, Igl and Johnson 1997), Le Conte's Sparrow populations exhibit numerical highs and lows depending on local moisture conditions (Peabody 1901, Stewart 1975, Knapton 1979, Zimmer 1979, Madden 1996). This observation, however, is based largely on anecdotal evidence or short-term observations. Long-term studies of Le Conte's Sparrow populations are limited. Le Conte's Sparrow is poorly represented on the North American Breeding Bird Survey (BBS) because of small sample sizes, poor coverage in the northern portion of its breeding range, and the species' furtive behavior (Sauer et al. 1995). Moreover, dramatic fluctuations in Le Conte's Sparrow abundance tend to obscure the species' long-term population trends on the BBS (Sauer et al. 1995). In this paper we examine long-term population changes of Le Conte's Sparrows breeding in perennial grassland fields enrolled in the Conservation Reserve Program (CRP) on the northern Great Plains. We discuss patterns of population change of Le Conte's Sparrows associated with changes in precipitation and moisture conditions.

Studies in Avian Biology↗
USGS2011

Occupancy and abundance of wintering birds in a dynamic agricultural landscape

Assessing wildlife management action requires monitoring populations, and abundance often is the parameter monitored. Recent methodological advances have enabled estimation of mean abundance within a habitat using presence–absence or count data obtained via repeated visits to a sample of sites. These methods assume populations are closed and intuitively assume habitats within sites change little during a field season. However, many habitats are highly variable over short periods. We developed a variation of existing occupancy and abundance models that allows for extreme spatio‐temporal differences in habitat, and resulting changes in wildlife abundance, among sites and among visits to a site within a field season. We conducted our study in sugarcane habitat within the Everglades Agricultural Area southeast of Lake Okeechobee in south Florida. We counted wintering birds, primarily passerines, within 245 sites usually 5 times at each site during December 2006–March 2007. We estimated occupancy and mean abundance of birds in 6 vegetation states during the sugarcane harvest and allowed these parameters to vary temporally or spatially within a vegetation state. Occupancy and mean abundance of the common yellowthroat ( Geothlypis trichas ) was affected by structure of sugarcane and uncultivated edge vegetation (occupancy = 1.00 [ = 0.96–1.00] and mean abundance = 7.9 [ = 3.2–19.5] in tall sugarcane with tall edge vegetation versus 0.20 [ = 0.04–0.71] and 0.22 [ = 0.04–1.2], respectively, in short sugarcane with short edge vegetation in one half of the study area). Occupancy and mean abundance of palm warblers ( Dendroica palmarum ) were constant (occupancy = 1.00, = 0.69–1.00; mean abundance = 18, = 1–270). Our model may enable wildlife managers to assess rigorously effects of future edge habitat management on avian distribution and abundance within agricultural landscapes during winter or the breeding season. The model may also help wildlife managers make similar management decisions involving other dynamic habitats such as wetlands, prairies, and even forested areas if forest management or fires occur during the field season.

Florida↗
USGS2013

Social-ecological predictors of global invasions and extinctions

Most assessments of resilience have been focused on local conditions. Studies focused on the relationship between humanity and environmental degradation are rare, and are rarely comprehensive. We investigated multiple social-ecological factors for 100 countries around the globe in relation to the percentage of invasions and extinctions within each country. These 100 countries contain approximately 87% of the world’s population, produce 43% of the world’s per capita gross domestic product (GDP), and take up 74% of the earth’s total land area. We used an information theoretic approach to determine which models were most supported by our data, utilizing an a priori set of plausible models that included a combination of 15 social-ecological variables, each social-ecological factor by itself, and selected social-ecological factors grouped into three broad classes. These variables were per capita GDP, export-import ratio, tourism, undernourishment, energy efficiency, agricultural intensity, rainfall, water stress, wilderness protection, total biodiversity, life expectancy, adult literacy, pesticide regulation, political stability, and female participation in government. Our results indicate that as total biodiversity and total land area increase, the percentage of endangered birds also increases. As the independent variables (agricultural intensity, rainfall, water stress, and total biodiversity) in the ecological class model increase, the percentage of endangered mammals in a country increases. The percentage of invasive birds and mammals in a country increases as per capita GDP increases. As life expectancy increases, the percentage of invasive and endangered birds and mammals increases. Although our analysis does not determine mechanisms, the patterns observed in this study provide insight into the dynamics of a complex, global, social-ecological system.

Ecology and Society↗
USGS2022

Grassland conservation supports migratory birds and produces economic benefits for the commercial beekeeping industry in the U.S. Great Plains

Although declines in grassland birds have been documented, national initiatives to conserve grasslands and their biota have fallen short in part because the non-market values of natural ecosystems and species are often not recognized in political decision making. Identifying shared, anthropogenic threats faced by market-valued and non-market-valued species may generate additional support for grassland conservation. We quantify the relationship between the market value of grasslands to commercial beekeepers and the importance of grasslands for birds of conservation concern in North and South Dakota. Our models estimated beekeeping annual revenue increased by $7525 USD and grassland bird abundances increased 2 to 7% per 10-km 2 increase in grassland area. We estimated grassland conversion from 2006 to 2012 resulted in a $2.0 to $2.8 M USD decrease in annual revenue for beekeepers in the Dakotas. Through this study we demonstrate both the market value of grasslands to commercial beekeepers and the non-market benefits of grasslands in supporting migratory birds and discuss the implications of future land-use change. As grassland conversion and subsequent biodiversity loss continue, understanding the co-benefits of grassland conservation may be necessary to illuminate their contributions to society.

North Dakota, South Dakota↗
USGS2013

Migration and wintering areas of American Bitterns ( Botaurus lentiginosus ) that summer in central North America as determined by satellite and radio telemetry, 1998-2003

Twenty adult male American Bitterns (Botaurus lentiginosus) were marked on summer range in central North America with satellite tracking Platform Transmitter Terminals (PTTs) to document migration routes and wintering range. Nineteen complete fall migration routes were documented for 17 individuals. Of the successful migrations, 63% (n = 12) went to southern Florida, 32% (n = 6) to southern Louisiana, and 5% (n = 1) to the Gulf coast of Texas. Spring migrations for nine birds were documented, and 78% (n = 7) showed fidelity to breeding range. Two complete migrations for two individuals were documented, and they demonstrated fidelity to winter range. The longest, fastest movement documented was 2,300 km in less than 74 hr. Extensive, post-breeding dispersal was not observed in the adult male American Bitterns in this study. Six male American Bitterns were marked with PTTs on winter range in Florida and Texas. Spring migration for these birds was documented to Nebraska, North Dakota, Saskatchewan, Manitoba and Ontario. Sixty-seven American Bitterns were marked with Very High Frequency radio transmitters on summer ranges, and 16% (n = 11) were located on wintering grounds used by the satellite-tracked birds, further documenting the importance of the Everglades and the Louisiana coast as winter habitat for American Bitterns that breed in Central North America.

Waterbirds↗
USGS2008

Modeling wetland blackbird populations as a function of waterfowl abundance in the prairie pothole region of the United States and Canada

Blackbirds share wetland habitat with many waterfowl species in Bird Conservation Region 11 (BCR 11), the prairie potholes. Because of similar habitat preferences, there may be associations between blackbird populations and populations of one or more species of waterfowl in BCR11. This study models populations of red-winged blackbirds and yellow-headed blackbirds as a function of multiple waterfowl species using data from the North American Breeding Bird Survey within BCR11. For each blackbird species, we created a global model with blackbird abundance modeled as a function of 11 waterfowl species; nuisance effects (year, route, and observer) also were included in the model. Hierarchical Poisson regression models were fit using Markov chain Monte Carlo methods in WinBUGS 1.4.1. Waterfowl abundances were weakly associated with blackbird numbers, and no single waterfowl species showed a strong correlation with any blackbird species. These findings suggest waterfowl abundance from a single species is not likely a good bioindicator of blackbird abundance; however, a global model provided good fit for predicting red-winged blackbird abundance. Increased model complexity may be required for accurate predictions of blackbird abundance; the amount of data required to construct appropriate models may limit this approach for predicting blackbird abundance in the prairie potholes. Copyright ?? Taylor & Francis Group, LLC.

Environmental Bioindicators↗
USGS2009

Effects of an unseasonable snowstorm on red-faced Warbler nesting success

Earlier initiation of nests by breeding birds may reflect an adaptive response to changes in food availability or warming of spring temperatures, but the consequences of initiating nests too early may be severe, particularly at high elevations. A rare snowstorm in late May 2008 resulted in nest abandonment by 68% of Red-faced Warblers (Cardellina rubrifrons) breeding in a high-elevation riparian ecosystem of southeastern Arizona. In addition, climate data from our study site from 1950 to 2008 revealed higher-than-average springtime temperatures during the past 10 years. If birds respond to this increase in springtime temperatures by nesting earlier their vulnerability to spring snowstorms may increase. ?? 2009 by The Cooper Ornithological Society. All rights reserved.

Condor↗
USGS2009

Fledging success is a poor indicator of the effects of bird blow flies on ovenbird survival

Infestations of bird blow flies ( Protocalliphora spp. and Trypocalliphora braueri ) have various negative effects on the condition of nestling birds. In the absence of other stressors such as inclement weather, however, infestation alone rarely reduces fledging success. Previous studies have documented effects of blow flies on nestling condition and fledging success. Without information regarding fledgling survival, the full effect of blow-fly infestation remains unclear. To fully investigate the effect of blow-fly infestation on reproductive success of the Ovenbird ( Seiurus aurocapilla ), we monitored infested and non-infested nests and monitored fledglings from each by using radio telemetry. Blow flies did not affect birds during the nestling period, as brood size, mean nestling mass, fledging success, and time to fledging in infested and non-infested nests were no different. Fledgling survival and minimum distance traveled the first day after fledging, however, were significantly lower for infected fledglings than for those that were not infected. We conclude that the stress of the early fledgling period combined with recent or concurrent blow-fly infection increases mortality in young Oven-birds. Our results demonstrate the importance of including the post-fledging period in investigations of the effects of ectoparasitic infestations on birds.

Minnesota↗
USGS2011

A trade-off between embryonic development rate and immune function of avian offspring is concealed by embryonic temperature

Long embryonic periods are assumed to reflect slower intrinsic development that are thought to trade off to allow enhanced physiological systems, such as immune function. Yet, the relatively rare studies of this trade-off in avian offspring have not found the expected trade-off. Theory and tests have not taken into account the strong extrinsic effects of temperature on embryonic periods of birds. Here, we show that length of the embryonic period did not explain variation in two measures of immune function when temperature was ignored, based on studies of 34 Passerine species in tropical Venezuela (23 species) and north temperate Arizona (11 species). Variation in immune function was explained when embryonic periods were corrected for average embryonic temperature, in order to better estimate intrinsic rates of development. Immune function of offspring trades off with intrinsic rates of embryonic development once the extrinsic effects of embryonic temperatures are taken into account.

Arizona↗
USGS2018

Visual cues for woodpeckers: light reflectance of decayed wood varies by decay fungus

The appearance of wood substrates is likely relevant to bird species with life histories that require regular interactions with wood for food and shelter. Woodpeckers detect decayed wood for cavity placement or foraging, and some species may be capable of detecting trees decayed by specific fungi; however, a mechanism allowing for such specificity remains unidentified. We hypothesized that decay fungi associated with woodpecker cavity sites alter the substrate reflectance in a species-specific manner that is visually discriminable by woodpeckers. We grew 10 species of wood decay fungi from pure cultures on sterile wood substrates of 3 tree species. We then measured the relative reflectance spectra of decayed and control wood wafers and compared them using the receptor noise-limited (RNL) color discrimination model. The RNL model has been used in studies of feather coloration, egg shells, flowers, and fruit to model how the colors of objects appear to birds. Our analyses indicated 6 of 10 decayed substrate/control comparisons were above the threshold of discrimination (i.e., indicating differences discriminable by avian viewers), and 12 of 13 decayed substrate comparisons were also above threshold for a hypothetical woodpecker. We conclude that woodpeckers should be capable of visually detecting decayed wood on trees where bark is absent, and they should also be able to detect visually species-specific differences in wood substrates decayed by fungi used in this study. Our results provide evidence for a visual mechanism by which woodpeckers could identify and select substrates decayed by specific fungi, which has implications for understanding ecologically important woodpecker–fungus interactions.

Wilson Journal of Ornithology↗
USGS2019

Avian influenza virus prevalence in marine birds is dependent on ocean temperatures

Waterfowl and shorebirds are the primary hosts of influenza A virus (IAV), however, in most surveillance efforts, large populations of birds are not routinely examined; specifically marine ducks and other birds that reside predominately on or near the ocean. We conducted a long-term study sampling sea ducks and gulls in coastal Maine for IAV and found a virus prevalence (1.7%) much lower than is typically found in freshwater duck populations. We found wide year-to-year variation in virus detection in sea ducks and that the ocean water temperature was an important factor affecting IAV prevalence. In particular, the ocean temperature that occurred 11 d prior to collecting virus positive samples was important while water temperature measured concurrently with host sampling had no explanatory power for viral detection. We also experimentally showed that IAV is relatively unstable in sea water at temperatures typically found during our sampling. This represents the first report of virus prevalence and actual environmental data that help explain the variation in marine IAV transmission dynamics.

Maine↗
USGS2023

A novel approach to assessing natural resource injury with Bayesian networks

Quantifying the effects of environmental stressors on natural resources is problematic because of complex interactions among environmental factors that influence endpoints of interest. This complexity, coupled with data limitations, propagates uncertainty that can make it difficult to causally associate specific environmental stressors with injury endpoints. The Natural Resource Damage Assessment and Restoration (NRDAR) regulations under the Comprehensive Environmental Response, Compensation, and Liability Act and Oil Pollution Act aim to restore natural resources injured by oil spills and hazardous substances released into the environment; exploration of alternative statistical methods to evaluate effects could help address NRDAR legal claims. Bayesian networks (BNs) are statistical tools that can be used to estimate the influence and interrelatedness of abiotic and biotic environmental variables on environmental endpoints of interest. We investigated the application of a BN for injury assessment using a hypothetical case study by simulating data of acid mine drainage (AMD) affecting a fictional stream-dwelling bird species. We compared the BN-generated probability estimates for injury with a more traditional approach using toxicity thresholds for water and sediment chemistry. Bayesian networks offered several distinct advantages over traditional approaches, including formalizing the use of expert knowledge, probabilistic estimates of injury using intermediate direct and indirect effects, and the incorporation of a more nuanced and ecologically relevant representation of effects. Given the potential that BNs have for natural resource injury assessment, more research and field-based application are needed to determine their efficacy in NRDAR. We expect the resulting methods will be of interest to many US federal, state, and tribal programs devoted to the evaluation, mitigation, remediation, and/or restoration of natural resources injured by releases or spills of contaminants

Integrated Environmental Assessment and Management↗
USGS1990

Birds of Islas Beata and Alto Velo, Dominican Republic

Isla Beata and Isla Alto Velo are small satellites of the Dominican Republic, lying off its southwestern coast. We visited Isla Beata between 26–30 July 1977 and 20–21 October 1978. We explored Isla Alto Velo on 22 October 1978. In addition we made aerial surveys of the islands in 1977 and 1980. In our surveys we found 34 species, including 16 land birds, not before reported for Isla Beata. The Hispaniolan Parakeet (Aratinga chloroptera) and Hispaniolan Woodpecker (Mélanerpes striatus) are reported for the first time from offshore islands. This brings the number of reported species for Isla Beata to 93, with 44 land birds. We found 22 species on Isla Alto Velo, for a total of 27 species, including 12 land birds, for the island.

Studies on Neotropical Fauna and Environment↗