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Greater Sage-Grouse Umbrella CCAA for Wyoming Ranch Management: a Candidate Conservation Agreement with Assurances for Greater Sage-Grouse Centrocercus urophasianus
Prior to settlement in the 19th century, greater sage-grouse (Centrocercus urophasianus; hereafter referred to as ‘sage-grouse’) inhabited 13 western States and three Canadian provinces, and their potential habitat covered over 1,200,483 square kilometers (km) (463,509 square miles (mi)). Sage-grouse have declined across their range due to a variety of causes and now occur in 11 States and two Canadian provinces. Many factors played a role in reducing sage-grouse from a once abundant, broadly distributed species, but the primary threat is loss of habitat due to increased surface disturbance and general fragmentation of the landscape. These concerns were identified in the 2005 Endangered Species Act (ESA) listing finding and remain so, but with more intensity and on a larger scale today. In the 2010 listing finding, additional concerns were identified as threats, including an increase in the use of sagebrush habitat for renewable energy such as wind power, and the spread of West Nile Virus (WNv).
In anticipation of a final listing decision by the U.S. Fish and Wildlife Service (FWS), the Wyoming Governor’s Office (WGO) requested assistance from the FWS in developing a sage-grouse strategy for ranch management activities that could offer private landowners assurances their livestock operations could continue in the event the species was listed under the ESA. The WGO and FWS in conjunction with the Bureau of Land Management (BLM), the Natural Resources Conservation Service (NRCS), the U.S Forest Service (USFS), the Wyoming Department of Agriculture (WDA), Wyoming Game and Fish Department (WGFD), and the Wyoming Association of Conservation Districts have developed this umbrella Candidate Conservation Agreement with Assurances (CCAA).
A CCAA is a voluntary agreement whereby private landowners agree to manage their lands to remove or reduce threats to species at risk of being listed under the ESA. In return for managing their lands to the benefit of species at risk, these landowners receive assurances against additional regulatory requirements should that species ever be listed under the ESA. Under a CCAA, the FWS will issue enrolled landowners Enhancement of Survival (EOS) permits pursuant to section 10(a)(1)(A) of the ESA for a period of 20 years. Since the agreement is voluntary, the landowner can end it at any point, although in doing so they would give up any assurances, and the EOS permit would terminate. FWS will issue EOS permits to participating landowners contingent on development of a site-specific individual sage-grouse conservation plan consistent with this umbrella CCAA. This umbrella CCAA includes:
A general description of responsibilities of all involved participating agencies and landowners, and the area covered under the umbrella CCAA;
Background, status and general threats to sage-grouse, and conservation measures needed to remove or reduce those identified threats;
Expected benefits of prescribed actions in relation to the five threat factors the FWS is required to evaluate when considering a species for listing; and
Level of take likely to occur from activities on enrolled lands, assurances, monitoring, and annual reporting
Where to Forage When Afraid: Does Perceived Risk Impair Use of the Foodscape?
The availability and quality of forage on the landscape constitute the foodscape within which animals make behavioral decisions to acquire food. Novel changes to the foodscape, such as human disturbance, can alter behavioral decisions that favor avoidance of perceived risk over food acquisition. Although behavioral changes and population declines often coincide with the introduction of human disturbance, the link(s) between behavior and population trajectory are difficult to elucidate. To identify a pathway by which human disturbance may affect ungulate populations, we tested the Behaviorally Mediated Forage‐Loss Hypothesis, wherein behavioral avoidance is predicted to reduce use of available forage adjacent to disturbance. We used GPS collar data collected from migratory mule deer (Odocoileus hemionus) to evaluate habitat selection, movement patterns, and time‐budgeting behavior in response to varying levels of forage availability and human disturbance in three different populations exposed to a gradient of energy development. Subsequently, we linked animal behavior with measured use of forage relative to human disturbance, forage availability, and quality. Mule deer avoided human disturbance at both home range and winter range scales, but showed negligible differences in vigilance rates at the site level. Use of the primary winter forage, sagebrush (Artemisia tridentata), increased as production of new annual growth increased but use decreased with proximity to disturbance. Consequently, avoidance of human disturbance prompted loss of otherwise available forage, resulting in indirect habitat loss that was 4.6‐times greater than direct habitat loss from roads, well pads, and other infrastructure. The multiplicative effects of indirect habitat loss, as mediated by behavior, impaired use of the foodscape by reducing the amount of available forage for mule deer, a consequence of which may be winter ranges that support fewer animals than they did before development
Estimating loss of Brucella abortus antibodies from age-specific serological data in elk
Serological data are one of the primary sources of information for disease monitoring in wildlife. However, the duration of the seropositive status of exposed individuals is almost always unknown for many free-ranging host species. Directly estimating rates of antibody loss typically requires difficult longitudinal sampling of individuals following seroconversion. Instead, we propose a Bayesian statistical approach linking age and serological data to a mechanistic epidemiological model to infer brucellosis infection, the probability of antibody loss, and recovery rates of elk (Cervus canadensis) in the Greater Yellowstone Ecosystem. We found that seroprevalence declined above the age of ten, with no evidence of disease-induced mortality. The probability of antibody loss was estimated to be 0.70 per year after a five-year period of seropositivity and the basic reproduction number for brucellosis to 2.13. Our results suggest that individuals are unlikely to become re-infected because models with this mechanism were unable to reproduce a significant decline in seroprevalence in older individuals. This study highlights the possible implications of antibody loss, which could bias our estimation of critical epidemiological parameters for wildlife disease management based on serological data
Wyoming Toad 3
AnimaliaCraniataAmphibiaAnuraBufonidaeBufoBreeding Season: May-JulyCompressed from .wav format into .mp3 delivery formatToad breeding calls at Mortenson Lake National Wildlife Refuge; Recorded June 15, 1989 at approximately 11 PM. "Mortenson Lake National Wildlife Refuge (NWR) supports the last known breeding population of the endangered Wyoming toad. The Refuge encompasses 1,776 acres and is located southwest of Laramie, Wyoming. The four main lakes on the Refuge are associated with a series of high elevation lakes called the 'Laramie plains lakes.'"- Source: US Fish and Wildlife Service; According to the conservation data center NatureServe, "In June 2002, a survey at Mortenson Lake NWR yielded 124 yearlings and 4 adults (USFWS 2002). Limited natural reproduction and recruitment of a few metamorphosed juveniles ocurred in 2002 (USFWS 2002)." See: http://www.natureserve.org/explorer/servlet/NatureServe?searchSpeciesUid=ELEMENT_GLOBAL.2.101600Local Time: 230