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Erika N Sanchez-Chopitea

Cartographic Technician

Western Ecological Research Center

Email: esanchez-chopitea@usgs.gov
Office Phone: 916-278-9483
Fax: 916-278-9475
ORCID: 0000-0003-2942-8417

Supervisor: Sarah E Spring
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To improve our understanding of health and immune function in tortoises, we evaluated both standard blood diagnostic (body condition, hematologic, plasma biochemistry values, trace elements, plasma proteins, vitamin A levels) and gene transcription profiles in 21 adult tortoises (11 clinically abnormal; 10 clinically normal) from Clark County, NV, USA. Necropsy and histology evaluations from clinically abnormal tortoises revealed multiple physiological complications, with moderate to severe rhinitis or pneumonia being the primary cause of morbidity in all but one of the examined animals. Improved methods for health assessments are an important element of monitoring tortoise population recovery and can support the...
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These data are .csv files of tagged sea otter re-sighting locations (henceforth, resights) collected in the field using a combination of VHF radio telemetry and direct observation using high powered (80x) telescopes. Sea otters were tracked by shore or boat-based observers from the date of tagging until the time of radio battery failure, the animal’s death, or the end of the project, whichever comes first. The frequency of re-sighting was opportunistic, depending on logistical factors such as coastal access, but generally ranged from daily to weekly. Location coordinates are reported latitude and longitude as well as X and Y coordinates in the projection/datum California Teale-Albers NAD 1927. The file contains...
The dataset summarizes total area (km2) and proportion of Central Valley waterbird habitat, summed across individual waterbird habitats (i.e., wetland and cropland types), that was available for each of 17 projected scenarios. The dataset also includes relatively recent (year 2005) area of existing habitat (i.e., “existing area”) for comparison with areas based on scenarios. Analysis was conducted for the projection period including water-years 2006–2099 (water-year defined as October-December and January–September of the following year). Because habitat areas vary through the season with timing of crop harvest and flooding of wetlands and post-harvested fields, annual areas and proportions represent summation...
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All plant species were identified down to finest taxa when possible. Each plant code used in the survey data is paired to a plant code on this species list which provides the full scientific name of each species, the plant family the species belongs to, the native or non-native status of species, and the life history of the plant. Plant nomenclature follows: Baldwin B.G., D.H. Goldman, D.J. Keil, R. Patterson, T.J. Rosatti, and D.H. Wilken, editors. 2012. The Jepson Manual: vascular plants of California. Second edition. University of California Press, Berkeley, USA.
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The current study was designed to provide critical information for resource managers (specifically the Bureau of Ocean Energy Management, henceforth BOEM, and the U.S. Fish and Wildlife Service, henceforth USFWS) about the spatial ecology, population status, and potential population threats to sea otters in Santa Barbara Channel, with particular reference to exposure to manmade structures and sources of oil and natural gas. Our four primary research objectives were: 1. Determine the extent of movements and spatial use patterns by sea otters along the southern California coast 2. Identify important sea otter resting and foraging areas adjacent to manmade structures 3. Assess sea otter distribution, behavior and...
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