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At least 1,045 records · Page 58Linked to original sources
USGS2011

Book review: Birds of Wyoming

"Wyoming may very well be one of the least birded states in the U.S." So begins this book, underscoring the challenges in summarizing existing knowledge for a state that falls next to last in human population density. Despite the relative dearth of "binoculars on the ground," especially in more remote areas of the state, the book offers a thorough compilation of relevant details. Much of this information is not readily accessible from other sources, and this book dispenses essential information in a very usable format. Review info: Birds of Wyoming . By Douglas W. Faulkner, 2010. ISBN: 978-1936221028, vii, 432 pp.

Prairie Naturalist↗
USGS2012

Microhabitat selection by bobcats in the badlands and Black Hills of South Dakota, USA: a comparison of Prairie and forested habitats

An understanding of habitat selection is important for management of wildlife species. Although bobcat (Lynx rufus) resource selection has been addressed in many regions of the United States, little work has been conducted in the Northern Great Plains. From 2006–2008 we captured and radiocollared 20 bobcats in the Badlands (n = 10) and Black Hills (n = 10) regions of South Dakota. During the summers of 2008 and 2009 we collected habitat measurements at 349 (176 Badlands, 176 Black Hills) bobcat locations and 321 (148 Badlands, 173 Black Hills) random sites. Microhabitat characteristics at bobcat use sites varied with region (P < 0.001) and sex of bobcat (P < 0.001). Percent slope, shrub, low cover, medium cover, and total cover were greater (P ≤ 0.017) at bobcat locations in the Black Hills than in the Badlands whereas distance to drainage was greater (P < 0.001) at locations in the Badlands than in the Black Hills. In the Badlands, male bobcat locations were closer (P ≤ 0.002) to prairie dog towns and drainages and had greater (P < 0.05) percent forbs and forb height than random sites, whereas females were closer to badland formations (P < 0.001) than random sites. In the Black Hills, male locations were at greater elevation (P < 0.001) and female locations were characterized by greater (P ≤ 0.02) grass height, shrub height, low cover, and total cover than random sites. Logistic regression indicated that microhabitat selection was similar between study areas; odds ratios indicated that odds of bobcat use increased by 0.998 (95% CI = 0.997–0.999) per 1 m increase in distance to drainage, 0.986 (95% CI = 0.978–0.993) per 1.0% increase in grass cover, by 1.024 (95% CI = 1.011–1.036) per 1 cm increase in grass height, by 1.013 (95% CI = 1.003–1.024) per 1% increase in forb cover, and by 1.028 (95% CI = 1.017–1.039) per 1% increase in medium cover. Our results were similar to other bobcat microhabitat selection studies, where bobcat relocations were associated with understory vegetation, drainages, and rugged terrain. These results identify the adaptability of the species to meet life history requirements in a variety of landscapes, and provide insight to how land use requirements vary within regional and management boundaries.

South Dakota↗
USGS2011

Habitat selection by female swift foxes (Vulpes velox) during the pup-rearing season

The swift fox (Vulpes velox) was historically distributed in western South Dakota including the region surrounding Badlands National Park (BNP). The species declined during the mid-1800s, largely due to habitat loss and poisoning targeted at wolves (Canis lupis) and coyotes (C. latrans). Only a small population of swift foxes near Ardmore, South Dakota persisted. In 2003, an introduction program was initiated at BNP with swift foxes translocated from Colorado and Wyoming. We report on habitat use by female swift foxes during the pup-rearing season (May&ndash;July) in 2009. Analyses of location data from 13 radiomarked female foxes indicated disproportional use ( P < 0.001) of some habitats relative to their availability within swift fox home ranges. Swift foxes used grassland ( &#374 = 1.01), sparse vegetation ( &#374 = 1.43) and prairie dog towns ( &#374 = 1.18) in proportion to their availability, whereas they were less likely to use woodland ( &#374 = 0.00), shrubland ( &#374 = 0.14), pasture/agricultural-land ( &#374 = 0.25) and development ( &#374 = 0.16) relative to availability. Swift foxes typically are located in habitats that provide greater visibility, such as shortgrass prairie and areas with sparse vegetation; which allow detection of approaching coyotes (e.g., primary predator of swift foxes).

South Dakota↗
USGS2011

Least Bittern nesting record in Maine

In June 2001, we located an active Ixobrychus exilis (Least Bittern) nest in Bass Harbor marsh on Mount Desert Island, Hancock County, ME. Only 2 other descriptions of Least Bittern nests exist for Maine, although based on other breeding evidence, the species is known to breed elsewhere in the state. We found the nest in a 0.7-ha Typha sp. (cattail)-dominated area within a larger (3.5 ha) freshwater wetland located ≈120 m from an 88-ha estuary. During the breeding season, most Least Bitterns in Maine and elsewhere are found in wetlands of greater size, usually >10 ha.

Maine↗
USGS2011

Minnesota wolf ear lengths as possible indicators of taxonomic differences

Genetic findings suggest that 2 types of wolves, Canis lupus (Gray Wolf) and C. lycaon (Eastern Wolf), and/or their hybrids occupy Minnesota (MN), and this study examines adult wolf ear lengths as a possible distinguisher between these two. Photographic evidence suggested that the Eastern Wolf possesses proportionately longer ears than Gray Wolves. Ear lengths from 22 northwestern MN wolves from the early 1970s and 22 Alaskan wolves were used to represent Gray Wolves, and the greatest length of the sample (12.8 cm) was used as the least length to demarcate Eastern Wolf from Gray Wolf influence in the samples. Twenty-three percent of 112 adult wolves from Algonquin Park in eastern Ontario and 30% of 106 recent adult wolves in northeastern MN possessed ears >12.8 cm. The northeastern MN sample differed significantly from that of current and past northwestern MN wolves. Ear-lengths of wolves in the eastern half of the northeastern MN wolf population were significantly longer than those in the western half of that study area, even though the mean distance between the 2 areas was only 40 km, and the mean length of my 2004&ndash;2009 sample was significantly longer than that of 1999&ndash;2003. These findings support the hypothesis that Eastern Wolves tend to possess longer ears than do Gray Wolves and suggest a dynamic hybridization process is still underway in MN.

Minnesota↗
USGS1994

Decline in a population of spectacled eiders nesting on the Yukon-Kuskokwim Delta, Alaska

The number of spectacled eiders nesting on two study areas near the Kashunuk River, on the central Yukon-Kuskokwim (Y-K) Delta, Alaska, declined by over 75% in the last 20 years. Nesting densities have remained low, but have not significantly declined since 1985. There has been no decrease in the reproductive effort of individual females as indicated by average clutch sizes. There has been a significant decline in the proportion of nests located on islands on one of the two study areas. Nesting success declined significantly during the 1970's. Success was not monitored in recent years, but has likely been low, based on the poor nesting success and declining numbers of cackling Canada geese and black brant nesting on the area. Nest predation by arctic foxes severely limited the productivity of cackling Canada geese, and foxes were likely the major predators of eider nests. Persistent high predation rates may lead to local extirpation in highly philopatric species such as eiders.

Northwestern Naturalist↗
USGS2009

Historical range, current distribution, and conservation status of the Swift Fox, Vulpes velox , in North America

The Swift Fox ( Vulpes velox ) was once common in the shortgrass and mixed-grass prairies of the Great Plains of North America. The species' abundance declined and its distribution retracted following European settlement of the plains. By the late 1800s, the species had been largely extirpated from the northern portion of its historical range, and its populations were acutely depleted elsewhere. Swift Fox populations have naturally recovered somewhat since the 1950s, but overall abundance and distribution remain below historical levels. In a 1995 assessment of the species' status under the US Endangered Species Act, the US Fish and Wildlife Service concluded that a designation of threatened or endangered was warranted, but the species was "precluded from listing by higher listing priorities." A major revelation of the 1995 assessment was the recognition that information useful for determining population status was limited. Fundamental information was missing, including an accurate estimate of the species' distribution before European settlement and an estimate of the species' current distribution and trends. The objectives of this paper are to fill those gaps in knowledge. Historical records were compiled and, in combination with knowledge of the habitat requirements of the species, the historical range of the Swift Fox is estimated to be approximately 1.5 million km 2 . Using data collected between 2001 and 2006, the species' current distribution is estimated to be about 44% of its historical range in the United States and 3% in Canada. Under current land use, approximately 39% of the species' historical range contains grassland habitats with very good potential for Swift Fox occupation and another 10% supports grasslands with characteristics that are less preferred (e.g., a sparse shrub component or taller stature) but still suitable. Additionally, land use on at least 25% of the historical range supports dryland farming, which can be suitable for Swift Fox occupation. In the United States, approximately 52% of highest quality habitats currently available are occupied by Swift Foxes.

Canadian Field-Naturalist↗
USGS1996

Sources of variation in counts of meristic features of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri)

We determined variability in counts of meristic features (pyloric caceae, vertebrae, pelvic fin rays, gill-rakers, basibranchial teeth, scales above the lateral line, and scales in the lateral series) of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) by 3 independent readers, by the same reader on 3 different occasions, and among fish from 12 sampling sites within a 650-km2 watershed. Genetic purity of the cutthroat trout was determined by electrophoretic analysis. Significant differences in meristic counts were observed among 3 readers and among sampling sites, but not among 3 occasions by a single reader. Scale counts were within the reported range for Yellowstone cutthroat trout, but counts of other structures (pyloric caceae, gillrakers, vertebrae) were as similar to rainbow trout as to Yellowstone cutthroat trout. Meristic counts identified the fish as cutthroat trout; however, variation among readers and sampling sites as well as within the species, limits their use when identifying genetically pure cutthroat trout or assessing possible integration with rainbow trout.

Great Basin Naturalist↗
USGS1998

Use and selection of brood-rearing habitat by Sage Grouse in south central Washington

Sage Grouse (Centrocercus urophasianus) brood-habitat use was examined during 1992 and 1993 at the Yakima Training Center in Yakima and Kittitas counties, Washington. During the 2 yr we followed 38 broods, of which 12 persisted to 1 August (x?? = approximately 1.5 chicks/brood). Food forb cover was greater at all brood locations than at random locations. Hens with broods in big sagebrush/bunchgrass habitat (Artemisia tridentata/Agropyron spicatum) selected for greater food forb cover, total forb cover, and lower shrub heights; broods in altered big sagebrush/bunchgrass habitats selected greater tall grass cover and vertical cover height; broods in grassland showed no preference for any measured vegetation characteristics. During the early rearing period (post-hatching-6 wk) each year, broods selected sagebrush/bunchgrass. Broods in 1993 made greater use of grasslands than in 1992 and selected grassland during the late brood-rearing period (7-12 wk). Broods selected for sagebrush/bunchgrass during midday, but 52% of brood locations in the afternoon were in grassland. Tall grass cover was greater at morning (0500-1000 h) and afternoon (1501-2000 h) brood locations than at midday (1001-1500 h) and random locations. Midday brood locations had greater shrub cover and height than morning and afternoon locations. Selection of habitat components was similar to the results of other studies, but habitat conditions coupled with a possible lack of 'alternate brood-rearing cover types resulted in low survival of chicks.

Great Basin Naturalist↗
USGS1999

Simulation modeling of population viability for the leopard darter (Percidae: Percina pantherina)

We used the computer program RAMAS to perform a population viability analysis for the leopard darter, Percina pantherina. This percid fish is a threatened species confined to five isolated rivers in the Ouachita Mountains of Oklahoma and Arkansas. A base model created from life history data indicated a 6% probability that the leopard darter would go extinct in 50 years. We performed sensitivity analyses to determine the effects of initial population size, variation in age structure, variation in severity and probability of catastrophe, and migration rate. Catastrophe (modeled as the probability and severity of drought) and migration had the greatest effects on persistence. Results of these simulations have implications for management of this species.

Southwestern Naturalist↗
USGS1999

Predatory bird populations in the east Mojave Desert, California

We surveyed 7 species of predatory birds weekly during a 12-month period (December 1992 through November 1993) in the east Mojave Desert, California. The Common Raven (Corvus corax) was the most frequently observed species with an average of 6.9 sightings per 100 km. Turkey Vultures (Cathartes aura), Red-tailed Hawks (Buteo jamaicensis), Loggerhead Shrikes (Lanius ludovicianus), American Kestrels (Falco sparverius), Golden Eagles (Aquila chrysaetos), and Prairie Falcons (Falco mexicanus) were seen in decreasing order of frequency of observation through the study period. Ravens, Red-tailed Hawks, Loggerhead Shrikes, American Kestrels, and Prairie Falcons were seen throughout the year. Turkey Vultures were not present during winter months, while Golden Eagles were seen only during November and December. Turkey Vultures, Red-tailed Hawks, and ravens were most numerous on agricultural lands, while Loggerhead Shrikes were most Common at urban areas. Raven numbers increased with increasing number of linear rights-of-way parallel to the survey route. Perching was the most common behavior type, although Turkey Vultures and ravens were often observed soaring, flying, or standing on the ground near highways. Transmission powerline towers and telephone poles were used as perch sites disproportionately to availability.

Great Basin Naturalist↗
USGS1999

First record of coccidiosis in Wolves, Canis Lupus

Three 4-month-old Wolf (Canis lupus) pups in the Superior National Forest of Minnesota died during August and September 1997, apparently from coccidiosis. This appears to be the first record of coccidiosis in Wolves.

Minnesota↗