Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “American Birds”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources
USGS2002

Distribution, abundance and habitat use of American White Pelicans in the Delta Region of Mississippi and along the Western Gulf of Mexico Coast

Aerial surveys of American White Pelicans ( Pelecanus erythrorhynchos ) were conducted over coastal Louisiana and the delta region of Mississippi on 1-2 days during December, February, and April each year from 1997 to 1999. Additional surveys were conducted in coastal Texas and Mexico during January 1998 and 1999. The numbers, location, and habitat of all pelicans observed were recorded. The coastal zone of Louisiana consistently had higher numbers of pelicans (18,000 to 35,000 birds) than other areas surveyed (3,000 to 8,000 birds), indicating that Louisiana may be the most important wintering area for American White Pelicans east of the Rocky Mountains. Among the four regions surveyed, the average size of pelican flocks was largest in Mississippi during January-February, particularly in 1999 (x̄ = 245 birds/flock). Pelican numbers in Mississippi peaked in February but in Louisiana they were more variable. Pelicans in the delta region of Mississippi were found most often in fresh water and sand bar habitats during December, flooded field habitats during February, and catfish ponds in April. In Louisiana, pelicans used fresh, intermediate, and brackish marshes during December, but showed a preference for brackish and saline marshes in February and April.

Louisiana, Mississippi, Tamaulipas, Texas, Veracru↗
USGS2005

Wetland restoration and birds: lessons from Florida, San Francisco Bay, and Chesapeake Bay

Many wetland restoration projects are underway across the North American landscape, ranging from small, community - based projects of less than 1 ha, to thousands of ha, as in San Francisco Bay or the Everglades. The goals of small projects are generally focused on replanting and sustaining native wetland vegetation, while larger projects often incorporate populations of birds and other vertebrates as part of the criteria for 'success.' Here, I use examples from a number of larger restoration projects from Florida, San Francisco Bay, and Chesapeake Bay, to illustrate several major challenges in planning and implementing those parts of the projects that include waterbirds. These include: (1) setting species priorities at the onset of the project, (2) negotiating among various stakeholders the goals that support wetland ecosystem structural elements (i.e. species and communities) versus those more functionally driven, (3) monitoring reproductive and survival parameters, as well as abundance, to avoid 'sink' situations, and (4) rationalizing control measures for opportunistic species that are not part of the restoration plan. Such projects often provide an ideal setting for the application of adaptive management, but long-term data management and oversight are required to ensure that project 'success' (or failure) is not short-term only.

Book chapter↗
USGS2014

Pharmacokinetics of buprenorphine hydrochloride following intramuscular and intravenous administration to American kestrels ( Falco sparverius )

Objective —To determine the pharmacokinetics of buprenorphine hydrochloride after IM and IV administration to American kestrels ( Falco sparverius ). Animals —13 healthy 3-year-old captive-bred American kestrels. Procedures —Buprenorphine hydrochloride (0.6 mg/kg) was administered IM to all birds. Blood samples were collected at 9 times, ranging from 5 minutes to 9 hours after drug administration. Plasma buprenorphine concentrations were measured by use of tandem liquid chromatography–mass spectrometry. Pharmacokinetic parameters were determined by use of least squares linear regression and noncompartmental analysis of naïve pooled data. After a washout period of 2 weeks, the same dose of buprenorphine was administered IV to all birds and blood samples were collected at the same times after drug administration. Results —Maximum plasma buprenorphine concentration was achieved within 5 minutes after IM administration. For IM administration, bioavailability was 94.8% and elimination half-life was 92.1 minutes. For IV administration, steady-state volume of distribution was 4,023.8 mL/kg, plasma clearance was 49.2 mL/min/kg, and elimination half-life was 105.5 minutes. Conclusions and Clinical Relevance —Buprenorphine was rapidly absorbed, and bioavailability was good after IM administration to American kestrels. Plasma buprenorphine concentrations were > 1 ng/mL for 9 hours after both IM and IV administration. These results, in combination with those of a pharmacodynamic study, suggested that the analgesic effects of buprenorphine could last at least 6 to 9 hours in this species. Further investigations of the duration of analgesic effects, multiple-dose protocols, and potential adverse effects of buprenorphine are warranted in American kestrels and other raptors.

American Journal of Veterinary Research↗
USGS2001

Associations of grassland birds with landscape factors in southern Wisconsin

We investigated the association of grassland birds with field- and landscape-level habitat variables in south-central Wisconsin during 1985–1987. Landscape-level variables were measured and digitized at 200, 400 and 800 m from the perimeter of 38 200 m × 100 m strip transects. A mixture of field and landscape variables was associated with the density of savannah sparrow ( Passerculus sandwichensis ) and grasshopper sparrow ( Ammodramus savannarum ). Only landscape variables were associated with the density of bobolink ( Dolichonyx oryzivorus ), eastern meadowlark ( Sturnella magna ) and all birds that were grassland species of management concern. Field size was not an important predictor of bird density. Cover-type diversity of the surrounding area was commonly selected in the models for three species and all birds that were grassland species of management concern. Higher bird densities in the transects were associated with landscapes where the cover types were less diverse. Landscapes with low cover type diversity were dominated by grassland, pasture and hay. Field habitat, mean patch size of cover types and distance to woody vegetation were the next most common predictors of avian density. The density of some grassland birds increased as nonlinear woody features such as woodlots and shrub carrs decreased in patch size, decreased in total amount in the landscape and increased in distance from a transect. However, density of other species was positively associated with linear woody features such as the total amount and nearness of hedgerows. The composition of the surrounding landscape, at least out to 800 m, is important in grassland bird management.

Wisconsin↗
USGS1972

Reproductive patterns in captive American kestrels (sparrow hawks)

Female kestrels acquired in Florida in winter as full-grown birds began laying eggs a month later than did those acquired as nestlings from northeastern United States. Egg laying dates of the two groups did not overlap in 1966 through 1968. The later nesting Florida-wintering females may have nested in captivity at a latitude farther south of their normal breeding range than did those from the Northeast. There was an apparent trend of earlier laying in successive years between 1965 and 1968 in our captive birds.....Time intervals between pairing of previously unpaired kestrels and initiation of their first clutches ranged from 8 to 17 days; time intervals between removal of first-clutch eggs and initiation of second clutches for kestrels whose first clutches failed to hatch ranged frosm 11 to 16 days, with the exception of an apparent anomaly of 40 days. Some females laid second clutches prior to fledging of first-clutch young. The egg laying interval averaged 2.4 days, and appeared to be greater between the first two and last two eggs of the clutch than between intervening eggs. Egg sizes differed only slightly between age groups, and no statistical correlation was evident between weights of female kestrels and the size of their eggs.....Although both sexes incubated the eggs, the female assumed a much greater role than the male. Incubation of clutches of five eggs usually began with the laying of the fourth egg. The incubation period (last egg laid to last egg hatched) averaged 27 days. The average interval between hatching of the first and last eggs of clutches containing five eggs was two days.....The average nestling period for the first young hatched in 29 nests was 28.4 days. An exact 1:l secondary sex ratio was recorded in 1967 for complete clutches in which all young fledged.

Condor↗
USGS2009

Filling a void: abundance estimation of North American populations of arctic geese using hunter recoveries

We consider use of recoveries of marked birds harvested by hunters, in conjunction with continental harvest estimates, for drawing inferences about continental abundance of a select number of goose species. We review assumptions of this method, a version of the Lincoln?Petersen approach, and consider its utility as a tool for making decisions about harvest management in comparison to current sources of information. Finally, we compare such estimates with existing count data, photographic estimates, or other abundance estimates. In most cases, Lincoln estimates are far higher than abundances assumed or perhaps accepted by many waterfowl biologists and managers. Nevertheless, depending on the geographic scope of inference, we suggest that this approach for abundance estimation of arctic geese may have usefulness for retrospective purposes or to assist with harvest management decisions for some species. Lincoln?s estimates may be as close or closer to truth than count, index, or photo data, and can be used with marking efforts currently in place for estimation of survival and harvest rates. Although there are bias issues associated with estimates of both harvest and harvest rate, some of the latter can be addressed with proper allocation of marks to spatially structured populations if subpopulations show heterogeneity in harvest rates.

Book chapter↗
USGS2002

Evaluation of management practices in wetland meadows at Grays Lake National Wildlife Refuge, Idaho, 1997-2000

We assessed the relative values of 4 management practices (idle, late season grazing, fall prescribed burning, and rotation of idle and summer grazing) to biotic resources of the grassland-wetland meadow ecosystem at Grays Lake during 1997-2000. Three replicates of each treatment were randomly assigned to 12 experimental units that bordered the deep emergent marsh. Biotic factors examined included the breeding bird community and abundance, nesting activity and nest success, small mammal abundance, plant community, and annual plant biomass production. Fall burns achieved treatment objectives, removing most residual vegetation across a range of cover types. Objectives for grazing treatments were mostly attained; however, vegetation use levels were insufficient for consistent attainment of treatment objectives. Savannah sparrow, American coot, Canada goose, sandhill crane, mallard, and yellow-headed blackbird were the most common bird species present. Densities of 2 bird species (savannah sparrow and red-winged blackbird) were related to year effect only. The effect of unit on densities of redhead, lesser scaup, ruddy duck, sora, long-billed curlew, and common snipe likely reflects habitat differences among units. Densities of 6 species (eared grebe, canvasback, American coot, American avocet, willet, and common yellowthroat) were related to both year and unit effects. Treatment affected densities of 6 of the 29 species examined (mallard, northern shoveler, cinnamon teal, blue-winged teal, American crow, and yellow-headed blackbird); we found no common trend in response to treatments among those species. Overall, idled habitat did not stand out to be a valuable treatment, whereas grazing tended to have positive responses for a number of species. Burning was more likely to result in reduced bird densities than other treatments. We also describe the distribution of species observations among 8 different habitat types. Of the 23 nesting species sampled in the experimental units, the most common were American coot, sandhill crane, Canada goose, American avocet, mallard, and cinnamon teal. Daily survival rates (DSRs) of dabbling duck nests (all species pooled) were negatively affected by fall grazing. We detected no effects of treatments on DSRs of Canada geese or sandhill crane nests. DSRs for sandhill crane nests were higher in 1998 than in 1999 or 2000 and were slightly higher than that in 1997. DSRs for coot nests were affected by both year and treatment; within-treatment differences among years were extensive, In 1998, when all units were idled, DSRs for coot nests were higher in units assigned to idle treatment than those assigned to fall-grazed or rotation treatment. DSRs for coot nests did not differ among treatment blocks in 1997 (all units idled) or 1999 (first year after treatments). We speculate that compaction of residual vegetation by snowpack reduced any differences between idle and treated units and thus lessened the value of idle habitat for most nesting birds. Nesting densities and nest success rates of Canada geese, dabbling ducks, and sandhill cranes were lower those that reported from Steel's (1952) study in 1949-1950, but differences in habitats and areas searched relative to our study make comparisons difficult. Nest success rates of sandhill cranes also were lower than those reported by Drewien (1973). Declines in nest success probably are related to changes in predator community. We captured 5 species of small mammals (meadow vole, montane vole, deer mouse, vagrant shrew, and ermine). Populations of meadow and montane voles irrupted in 1998 then crashed in spring 1999; the most marked changes were in montane vole numbers. Capture rates of ermine and observation rates for striped skunks and raptors suggested a numerical response (higher recruitment) by these predators to higher prey abundance and possibly distributional shifts (movement into areas of more abundant microtines). We did not detect differences

Report↗
USGS1997

Conservation of Mexican wetlands: role of the North American Wetlands Conservation Act

Mexico's wetlands support a tremendous biological diversity and provide significant natural resource benefits to local communities. Because they are also critical stopover and wintering grounds for much of North America's waterfowl and other migratory birds, Mexico has become an important participant in continental efforts to conserve these resources through the North American Wetlands Conservation Act. Funding from the Act has supported partnerships in a number of Mexico's priority wetlands to conduct data analyses and dissemination, mapping, environmental education, wetland restoration, development of sustainable economic alternatives for local people, and reserve planning and management. These partnerships, with the close involvement of Mexico's Federal Government authority, the Instituto Nacional de Ecologia, have advanced conservation in a uniquely Mexican model that differs from that employed in the United States and Canada.

Wildlife Society Bulletin↗
USGS1995

Neotropical migrant landbirds and landscape changes in Los Tuxtlas, Veracruz, Mexico

Faced with the problem of habitat loss and with the need to preserve the remaining components of the original avian biodiversity in neotropical regions such as Los Tuxtlas, it is imperative to determine how the neotropical migrant bird species have responded to the anthropogenic alterations of their natural habitats. To provide data in this direction, we censused neotropical migrant birds in undisturbed and in disturbed forest fragments and in regeneratlng forests (young second growths and old second growths). In addition, we conducted censuses in the following man-made habitats: arboreal agricultural habitats (cacao, coffee, mixed, citrus, and allspice), non-arboreal agricultural habitats (corn and jalapeno chili pepper), live fences, and pastures. We censused 4186 neotropical migrant birds representing 71 species. Seven species (Magnolia Warbler, Hooded Warbler, Wilson's Warbler, American Redstart, White-eyed Vireo, Yellow-rumped Warbler, Black-and-white Warbler) accounted for 50% of total records. Isolating distance was an important variable influencing species richness at the non-pasture habitats studied. Disturbed forest fragments had significantly fewer species and individuals than undisturbed forest fragments and than regenerating forests. Pastures were the poorest habitat in neotropical migrant birds. Agricultural habitats, however, were particularly rich in individuals and species (3479 individuals of 59 species). Arboreal agricultural habitats and live fences were richer in species and in birds than non-arboreal man-made habitats and were also the habitats most similar to the undisturbed forest fragments in species assemblage. We discuss the conservation value for neotropical migrant birds of agricultural habitats and of live fences as landscape elements that help reduce physical and biotic isolation among the remaining configurations of forest fragments and compensate, in part, for the loss of vegetation area and habitat heterogeneity that has resulted from anthropogenic activity in Los Tuxtlas.

Book chapter↗
USGS1996

Survival and recovery rates of American eiders in eastern North America

We analyzed banding and recovery data of adult female American eiders ( Somateria mollissima dresseri ) captured during the breeding season in eastern North America. We estimated survival rates for birds originating in the Atlantic Coast subpopulation to be 0.8730 ± 0.0156 (SE) while recovery rates were 0.0101 ± 0.0080 (SE). Support for several banding reference areas of American eiders was found. No trends were detected in band recovery, harvest rates or harvest over time.

Journal of Wildlife Management↗
USGS1968

Possible differentiation of natal areas of North American waterfowl by neutron activation analysis

The possibility of using neutron activation analyses to differentiate sources of North American waterfowl was investigated by irradiating rectrices and wing bones of birds collected in several localities, and comparing the characteristic gamma-ray spectra. Canada goose ( Branta canadensis ) rectrices from Oregon specimens could be distinguished from those taken in Wisconsin and Colorado based on higher levels of Mn. Mallard ( Anas platyrhynchos ), black duck ( A. rubripes ), and blue-winged teal ( A. discors ) wing bones from Wisconsin, Colorado, and New Brunswick could not be clearly identified as to locality from levels of Ca, Al, Na, Mn, and Cl.

Colorado, Oregon, Wisconsin↗
USGS2019

Detection probability and occupancy of American woodcock during Singing-ground surveys

The Singing-ground Survey (SGS) was designed to exploit the conspicuous breeding-season display of male American woodcock ( Scolopax minor ; hereafter, woodcock) to monitor these otherwise inconspicuous birds. The SGS was standardized in 1968 and has since been conducted annually to derive an index of abundance and population trend. Counts of singing male woodcock on the SGS have generally declined through time, but without knowledge of the relationship among counts, woodcock abundance, and the factors affecting detection, considerable uncertainty remains in interpretation of SGS data. Using modified SGS protocols, we surveyed SGS routes in Pine County, Minnesota, in 2009 and 2010 and developed models to assess factors associated with detection probability and estimated occupancy. The intercept-only model (i.e., constant detection and occupancy probabilities across sites and no covariates) included overall detection probability of 0.59 (SE = 0.018) in 2009 and 0.66 (SE = 0.017) in 2010 with an occupancy estimate of 0.74 (SE = 0.049) in 2009 and 0.81 (SE = 0.044) in 2010. The best-supported model of detection probability for both years combined included detection as a function of woodcock abundance, observer, date, disturbance level (i.e., ambient noise that interfered with detecting woodcock), and wind speed. High wind speeds were negatively related to detection, different observers had different detection probabilities, date was quadratically related to detection (indicating a mid-period peak in detection), and high woodcock abundance and low disturbance levels were positively related to detection. We provide suggestions for incorporating these resulting into SGS protocol and analyses.

Minnesota↗
USGS2015

Introduction

This is the third iteration of the National Wildlife Health Center's (NWHC) field guide developed primarily to assist field managers and biologists address diseases they encounter. By itself, the first iteration, “Field Guide of Wildlife Diseases: General Field Procedures and Diseases of Migratory Birds,” was simply another addition to an increasing array of North American field guides and other publications focusing on disease in free-ranging wildlife populations. Collectively, those publications were reflecting the ongoing transition in the convergence of wildlife management and wildlife disease as foundational components within the structure of wildlife conservation as a social enterprise serving the stewardship of our wildlife resources. For context, it is useful to consider those publications relative to a timeline of milestones involving the evolution of wildlife conservation in North America.

Techniques and Methods↗
USGS2018

Hematological indices of injury to lightly oiled birds from the Deepwater Horizon oil spill

Avian mortality events are common following large‐scale oil spills. However, the sublethal effects of oil on birds exposed to light external oiling are not clearly understood. We found that American oystercatchers (area of potential impact n = 42, reference n = 21), black skimmers (area of potential impact n = 121, reference n = 88), brown pelicans (area of potential impact n = 91, reference n = 48), and great egrets (area of potential impact n = 57, reference n = 47) captured between 20 June 2010 and 23 February 2011 following the Deepwater Horizon oil spill experienced oxidative injury to erythrocytes, had decreased volume of circulating erythrocytes, and showed evidence of a regenerative hematological response in the form of increased reticulocytes compared with reference populations. Erythrocytic inclusions consistent with Heinz bodies were present almost exclusively in birds from sites impacted with oil, a finding pathognomonic for oxidative injury to erythrocytes. Average packed cell volumes were 4 to 19% lower and average reticulocyte counts were 27 to 40% higher in birds with visible external oil than birds from reference sites. These findings provide evidence that small amounts of external oil exposure are associated with hemolytic anemia. Furthermore, we found that some birds captured from the area impacted by the spill but with no visible oiling also had erythrocytic inclusion bodies, increased reticulocytes, and reduced packed cell volumes when compared with birds from reference sites. Thus, birds suffered hematologic injury despite no visible oil at the time of capture. Together, these findings suggest that adverse effects of oil spills on birds may be more widespread than estimates based on avian mortality or severe visible oiling.

Environmental Toxicology and Chemistry↗
USGS2014

North Atlantic migratory bird flyways provide routes for intercontinental movement of avian influenza viruses

Avian influenza virus (AIV) in wild birds has been of increasing interest over the last decade due to the emergence of AIVs that cause significant disease and mortality in both poultry and humans. While research clearly demonstrates that AIVs can move across the Pacific or Atlantic Ocean, there has been no data to support the mechanism of how this occurs. In spring and autumn of 2010 and autumn of 2011 we obtained cloacal swab samples from 1078 waterfowl, gulls, and shorebirds of various species in southwest and west Iceland and tested them for AIV. From these, we isolated and fully sequenced the genomes of 29 AIVs from wild caught gulls (Charadriiformes) and waterfowl (Anseriformes) in Iceland. We detected viruses that were entirely (8 of 8 genomic segments) of American lineage, viruses that were entirely of Eurasian lineage, and viruses with mixed American-Eurasian lineage. Prior to this work only 2 AIVs had been reported from wild birds in Iceland and only the sequence from one segment was available in GenBank. This is the first report of finding AIVs of entirely American lineage and Eurasian lineage, as well as reassortant viruses, together in the same geographic location. Our study demonstrates the importance of the North Atlantic as a corridor for the movement of AIVs between Europe and North America.

North Atlantic↗
USGS1990

Renesting by American woodcocks ( Scolopax minor ) in Maine

The American Woodcock ( Scolopax minor ) is one of the earliest ground-nesting birds in the northeastern United States. In Maine, nesting begins in early April when temperatures can drop below freezing and significant snowfall can accumulate. Nests are usually in open woods, where eggs are laid on the ground in a shallow depression (Pettingill 1936, Mendall and Aldous 1943, Sheldon 1967). Peak hatching occurs in early May (Dwyer et al. 1982), when temperatures are cool and precipitation is common. Woodcock chicks are dependent on the female for most of their food for at least seven days after hatching (Gregg 1984). During cool, wet weather, chicks require constant brooding by females; prolonged periods of inclement weather may lead to substantial mortality of chicks (Dwyer et al. 1988).

The Auk↗