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Energy, Land Use, and Sagebrush Ecosystems: Finding the Delicate Balance

This web resource is a compilation of research projects related to Energy, Land Use, and Sagebrush Ecosystems. Investigators at the USGS Science Centers (FORT and FRESC), and Central Regional Office have brought biological and ecosystem research and mapping expertise to a partnership with the Bureau of Land Management, Wyoming Game and Fish More...

  • Photo of a badger

Development of a Bioassay to Quantify Vitellogenin in the Endangered Razorback Sucker followed by Annual Cycle Characterization of Vitellogenin and Steroid Hormones as a Measure of Reproductive Health

This research project objective is to measure vtg and steroid hormones in sexually mature, adult razorback sucker over one annual -estradiol,ß reproductive cycle. We will measure vtg and steroid hormones (17 11-ketotestosterone, and testosterone) in blood plasma of razorback suckers once a month for one year to document concentrations throughout More...

  • Razorback Sucker (Xyrauchen texanus)

Manatee Research (Sirenia Project)

Web page for the Sirenia Project, a USGS Florida Integrated Science Center project that conducts studies on the West Indian manatee (Trichechus manatus). Includes links to manatee research in the news, international research, publications and presentations, and project staff contact information.

  • close up of a manatee

Streamflow and Endangered Species Habitat in the Lower Isleta Reach of the Middle Rio Grande

San Acacia Dam is located in a reach of the Rio Grande that has been designated as critical habitat for two endangered species, the Rio Grande silvery minnow (Hybognathus amarus) and the southwestern willow flycatcher (Empidonax traillii extimus). Presently, Rio Grande upstream from the dam is used to convey irrigation water to the Socorro main More...

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Monitoring Populations of Sage-Grouse: Proceedings of a Symposium at Idaho State University Hosted by University of Idaho and Idaho State University

The greater sage-grouse (Centrocercus urophasianus) and the Gunnison sage-grouse (C. minimus) are species of concern because of their population declines and shrinking geographic distributions. Of continuing interest is the question of population abundance and trends. This publication answers the questions that deal with sage-grouse population, More...

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Southwestern Willow Flycatcher Breeding Site and Territory Summary (2006)

The Southwestern Willow Flycatcher (Empidonax traillii extimus) is an endangered bird that breeds only in dense riparian habitats in six southwestern states (southern California, extreme southern Nevada, southern Utah, southwestern Colorado, Arizona, and New Mexico). This report synthesizes information on all known Southwestern Willow Flycatcher More...

  • Willow flycatcher (Empidonax traillii)

Molecular and phenotypic diversity in Chionactis occipitalis (Western Shovel-nosed Snake), with emphasis on the status of C. o. klauberi (Tucson Shovel-nosed Snake)

The Alameda whipsnake (Masticophis lateralis euryxanthus) is both a federally and state listed endangered species limited to scrub and chaparral habitat within Contra Costa and Alameda Counties, CA. Loss and fragmentation of habitat due to agricultural and urban development over the last 100 years are cited as the main causes of its decline. Based More...

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Amphibian Monitoring in the Canyon Country of the Colorado Plateau

At least 13 amphibian species are found on the Colorado Plateau, although some have very limited distributions in this bioregion. Amphibian declines have been documented in many parts of the world, but knowledge of amphibians on the Colorado Plateau is inadequate to determine population status or trends for most species. The U.S. Geological More...

  • ARMI website logo

Geographic Variation and Environmental Determinants of Reproductive Output in the Desert Tortoise

The desert tortoise is listed as a threatened species under federal and California versions of the Endangered Species Act. The recovery plan for the desert tortoise recommended that additional data be collected on the reproductive ecology of the species throughout the range. Annual meetings between USGS, Biological Resources Division researchers More...

  • image of an adult male tortoise

Data from the 2006 International Piping Plover Census

This report presents the results of the 2006 International Census of Piping Plovers (Charadrius melodus). Two sets of tabular data are reported: one for distribution and abundance of wintering Piping Plovers, the other for distribution and abundance of breeding Piping Plovers. The winter census resulted in the observation of 3,884 Piping Plovers More...

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Evaluating the Role of Wetlands to Endangered Salmonids at Toppenish and Tualatin River National Wildlife Refuge

Threatened and endangered salmonids in the Pacific Northwest often use backwaters and wetlands as they migrate toward the ocean, however our understanding of the role of wetlands to juvenile salmonids is limited. The major Objective of this study was to determine whether juvenile steelhead were being tapped on the wetland during spring, and More...

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Using Proportion of Area Occupied to Estimate Abundance of Amphibians in Everglades National Park and Big Cypress National Preserve

This project uses data on detection of amphibian species after repeated sampling at a site to estimate the occupancy rate of various amphibian species (MacKenzie et al., 2002). Declines in amphibian populations have been documented for many regions and habitat types worldwide (Alford and Richards, 1999). No single cause for declines has been More...

  • Florida leopard frog, Rana sphenocephala