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Eric J. Kolada

Publications and source records attributed to Eric J. Kolada.

3 recordsLinked to original sources

Nest site selection by greater sage-grouse in Mono County, California

Loss of nesting habitat is believed to be a factor in the decline of greater sage-grouse ( Centrocercus urophasianus ) throughout its range. Few data are available for sage-grouse in Mono County, California, USA, in the most southwestern portion of the species' range. We studied habitat selection of nesting sage-grouse in Mono County, California, from 2003 to 2005 by capturing and radiotracking females to identify nesting locations. We sampled vegetation at nest sites and randomly selected sites within 200 m of nests and within each of 5 subareas within Mono County. Nest sites were characterized by 42.4 ± 1.3% ( x ¯ ± SE) shrub canopy cover, 10.5 ± 1.0 cm residual grass height, and 2.7 ± 1.0% residual grass cover. Shrub cover was the only variable found to differentiate nest sites from randomly selected sites. Unlike some other studies, we did not find understory vegetation to be important for selecting nest sites. Mean shrub cover was 38.7 ± 1.5% at random sites within 200 m of nests and 33.6 ± 1.6% at random sites at the approximate scale of home ranges, indicating that nesting females selected nesting areas that contained denser shrubs than their home range, and nest sites that contained greater shrub cover than the vicinity immediately surrounding nests. Our results suggest that managers should consider managing for greater shrub cover in Mono County than what is currently called for in other parts of sage-grouse range and that management for sage-grouse habitat may need to be tied more closely to local conditions.

California

Ecological factors influencing nest survival of greater sage-grouse in Mono County, California

We studied nest survival of greater sage-grouse ( Centrocercus urophasianus ) in 5 subareas of Mono County, California, USA, from 2003 to 2005 to 1) evaluate the importance of key vegetation variables for nest success, and 2) to compare nest success in this population with other greater sage-grouse populations. We captured and radiotracked females ( n = 72) to identify nest sites and monitor nest survival. We measured vegetation at nest sites and within a 10-m radius around each nest to evaluate possible vegetation factors influencing nest survival. We estimated daily nest survival and the effect of explanatory variables on daily nest survival using nest-survival models in Program MARK. We assessed effects on daily nest survival of total, sagebrush ( Artemisia spp.), and nonsagebrush live shrub-cover, Robel visual obstruction, the mean of grass residual height and grass residual cover measurements within 10 m of the nest shrub, and area of the shrub, shrub height, and shrub type at the nest site itself. Assuming a 38-day exposure period, we estimated nest survival at 43.4%, with percent cover of shrubs other than sagebrush as the variable most related to nest survival. Nest survival increased with increasing cover of shrubs other than sagebrush. Also, daily nest survival decreased with nest age, and there was considerable variation in nest survival among the 5 subareas. Our results indicate that greater shrub cover and a diversity of shrub species within sagebrush habitats may be more important to sage-grouse nest success in Mono County than has been reported elsewhere.

California

Ecology of Greater Sage-Grouse in the Bi-State Planning Area Final Report, September 2007

Conservation efforts for greater sage-grouse (Centrocercus urophasianus), hereafter sage-grouse, are underway across the range of this species. Over 70 local working groups have been established and are implementing on-the-ground sage-grouse oriented conservation projects. Early on in this process, the California Department of Fish and Game (CDFG) recognized the need to join in these efforts and received funding from the U.S. Fish and Wildlife Service (USFWS) under the Candidate Species Conservation Program to help develop a species conservation plan for sage-grouse in the Mono County area. This conservation plan covers portions of Alpine, Mono, and Inyo counties in California and Douglas, Esmeralda, Lyon, and Mineral counties in Nevada. A concurrent effort underway through the Nevada Governor's Sage-grouse Conservation Team established Local Area Working Groups across Nevada and eastern California. The Mono County populations of sage-grouse were encompassed by the Bi-State Local Planning Area, which was comprised of six population management units (PMUs). The state agencies from California (CDFG) and Nevada (Nevada Department of Wildlife; NDOW) responsible for the management of sage-grouse agreed to utilize the process that had begun with the Nevada Governor's Team in order to develop local plans for conservation planning and implementation. Resources from the USFWS were applied to several objectives in support of the development of the Bi-State Local Area Sage-grouse Conservation Plan through a grant to the U.S. Geological Survey (USGS). Objectives included: (1) participate in the development of the Bi-State Conservation Plan, (2) compile and synthesize existing sage-grouse data, (3) document seasonal movements of sage-grouse, (4) identify habitats critical to sage-grouse, (5) determine survival rates and identify causal factors of mortality, (6) determine nest success and brood success of sage-grouse, and (7) identify sage-grouse lek sites. Progress reports completed in 2004 and 2005 addressed each of the specific objectives and this final report focuses on the biological information gathered in support of local conservation efforts. Participation in the development of the Bi-State Local Area Conservation Plan was accomplished on multiple scales. Beginning in the fall of 2002, USGS personnel began participating in meetings of local stakeholders involved in the development of a sage-grouse conservation plan for the Bi-State planning area. This included attendance at numerous local PMU group meetings and field trips as well as participating on the technical advisory committee (TAC) for the Bi-State group. Whenever appropriate, ongoing results and findings regarding sage-grouse ecology in the local area were incorporated into these working group meetings. In addition, the USGS partnered with CDFG to help reorganize one of the local PMU groups (South Mono) and edited that portion of the Bi-State plan. The USGS also worked closely with CDFG to draft a description of the state of knowledge for sage-grouse genetic information for inclusion in the Bi-State Conservation Plan. The first edition of the Bi-State Conservation Plan for Greater Sage-Grouse was completed in June 2004 (Bi-State Sage-grouse Conservation Team 2004). This report is organized primarily by PMU to facilitate the incorporation of these research findings into the individual PMU plans that compose the Bi-State plan. Information presented in this report was derived from over 7,000 radio-telemetry locations obtained on 145 individual sage-grouse during a three year period (2003-2005). In addition, we collected detailed vegetation measurements at over 590 habitat sampling plots within the study area including canopy cover, shrubs, forbs, and grasses diversity. Vegetation data collection focused on sage-grouse nests, and brood-use areas. Additionally we collected data at random sites to examine sage-grouse habitat relationships within the study area. The majori

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