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Patrick S Kolar

I am a Wildlife Biologist at the USGS Forest and Rangeland Ecosystem Science Center in Corvallis, OR

Science and Products

If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.

Detection/non-detection data on territorial pairs of golden eagles in coastal southern California, 2016-2017

This dataset contains detection-nondetection data for territorial pairs of Golden Eagles at survey sites randomly selected from a grid of equal-sized (13.9 km2) hexagonal sample cells overlaid across the region of interest in Coastal Southern California during 2016 and 2017. We partitioned surveys within seasons based on approximate transition dates for stages in the breeding cycle of golden eagle
By
Forest and Rangeland Ecosystem Science Center
A person standing by a spotting scope on a tripod, looking through binoculars. Grassy hills and rainbow in background
Surveying for Golden Eagles in California
Surveying for Golden Eagles in California
A person standing by a spotting scope on a tripod, looking through binoculars. Grassy hills and rainbow in background

Surveying for Golden Eagles in California

Surveying for Golden Eagles in California

Patrick Kolar, wildlife biologist at the Forest and Rangeland Ecosystem Science Center, surveys for territorial pairs of golden eagles using binoculars and a spotting scope in the Diablo Range study area of central California.

By
Forest and Rangeland Ecosystem Science Center
A person standing by a spotting scope on a tripod, looking through binoculars. Grassy hills and rainbow in background

Surveying for Golden Eagles in California

Surveying for Golden Eagles in California

Patrick Kolar, wildlife biologist at the Forest and Rangeland Ecosystem Science Center, surveys for territorial pairs of golden eagles using binoculars and a spotting scope in the Diablo Range study area of central California.

By
Forest and Rangeland Ecosystem Science Center

If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.

Golden Eagle (Aquila chysaetos)

The golden eagle (Aquila chrysaetos) is commonly recognized as an indicator of ecosystem health and was selected as an important indicator species for the ecological health of lands owned and managed by East Bay Stewardship Network (Network) partner agencies within the area of focus for this project (See map, Chapter 1). Based on national conservation goals and past and current golden eagle resear
Authors
David Wiens, Patrick Kolar, Douglas A. Bell
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Golden eagle occupancy surveys and monitoring strategy in coastal southern California, United States

Golden eagles (Aquila chrysaetos) are of increasing conservation concern in western North America. Effective conservation measures for this wide-ranging, federally protected raptor species require monitoring frameworks that accommodate strong inference on the status of breeding populations across vast landscapes. We used a broad-scale sampling design to identify relationships between landscape con
Authors
David Wiens, Peter H. Bloom, Melanie C. Madden, Patrick Kolar, Jeff A. Tracey, Robert N. Fisher
By
Ecosystems Mission Area, Cooperative Research Units, Forest and Rangeland Ecosystem Science Center, Western Ecological Research Center (WERC)

Golden eagle population surveys in the vicinity of the Altamont Pass Wind Resource Area, California, 2014–21

Golden Eagles (Aquila chrysaetos) are among the highest profile species killed by collisions with wind turbines at the Altamont Pass Wind Resource Area (APWRA) in the northern Diablo Range of west-central California. Understanding the distribution, site occupancy, and nesting status of eagles near the APWRA is needed to identify and minimize possible population-level impacts. We established a broa
Authors
J. David Wiens, Patrick S. Kolar
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Distribution and abundance of Aquila chrysaetos (golden eagles) in East Contra Costa County Habitat Conservation Plan/Natural Community Conservation Plan area, California

The East Contra Costa County Habitat Conservation Plan/Natural Community Conservation Plan (HCP/NCCP) Preserve System was designed to protect and enhance ecological diversity and function in eastern Contra Costa County, California. Aquila chrysaetos (golden eagle) is a special-status species expected to benefit from biological goals of the HCP/NCCP. As part of a broader study, we estimated site-oc
Authors
J. David Wiens, Patrick S. Kolar, Douglas A. Bell
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Raptor interactions with wind energy: Case studies from around the world

The global potential for wind power generation is vast, and the number of installations is increasing rapidly. We review case studies from around the world of the effects on raptors of wind-energy development. Collision mortality, displacement, and habitat loss have the potential to cause population-level effects, especially for species that are rare or endangered. The impact on raptors has much t
Authors
Richard T. Watson, Patrick S. Kolar, Miguel Ferrer, Torgeir Nygård, Naira Johnston, W. Grainger Hunt, Hanneline A. Smit-Robinson, Christopher J Farmer, Manuela M. Huso, Todd E. Katzner
By
Ecosystems Mission Area, Species Management Research Program, Forest and Rangeland Ecosystem Science Center

Golden Eagle Monitoring Plan for the Desert Renewable Energy Conservation Plan

This report describes options for monitoring the status and population trends of the golden eagle (Aquila chrysaetos) within the Desert Renewable Energy Conservation Plan (DRECP) area of Southern California in maintaining stable or increasing population in the planning area. The report profiles the ecology of golden eagles in the region and provides a range of potential sampling options to address
Authors
David Wiens, Patrick Kolar, Todd E. Katzner
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Spatial patterns in occupancy and reproduction of Golden Eagles during drought: Prospects for conservation in changing environments

We used a broad-scale sampling design to investigate spatial patterns in occupancy and breeding success of territorial pairs of Golden Eagles (Aquila chrysaetos) in the Diablo Range, California, USA, during a period of exceptional drought (2014–2016). We surveyed 138 randomly selected sample sites over 4 occasions each year and identified 199 pairs of eagles, 100 of which were detected in focal sa
Authors
David Wiens, Patrick Kolar, W. Grainger Hunt, Teresa Hunt, Mark R. Fuller, Douglas A. Bell
By
Ecosystems Mission Area, Species Management Research Program, Forest and Rangeland Ecosystem Science Center

Distribution, nesting activities, and age-class of territorial pairs of golden eagles at the Altamont Pass Wind Resource Area, California, 2014–16

The substantial numbers of golden eagles (Aquila chrysaetos) killed by collisions with oldgeneration wind turbines each year at the Altamont Pass Wind Resource Area (APWRA) in California has been well documented from previous studies. Few eagle nests have been documented in the APWRA, however, and adults and subadults 3+ years of age killed by turbines were generally not associated with nearby ter
Authors
Patrick S. Kolar, J. David Wiens
By
Ecosystems Mission Area, Species Management Research Program, Forest and Rangeland Ecosystem Science Center

Estimation of occupancy, breeding success, and predicted abundance of golden eagles (Aquila chrysaetos) in the Diablo Range, California, 2014

We used a multistate occupancy sampling design to estimate occupancy, breeding success, and abundance of territorial pairs of golden eagles (Aquila chrysaetos) in the Diablo Range, California, in 2014. This method uses the spatial pattern of detections and non-detections over repeated visits to survey sites to estimate probabilities of occupancy and successful reproduction while accounting for imp
Authors
J. David Wiens, Patrick S. Kolar, Mark R. Fuller, W. Grainger Hunt, Teresa Hunt
By
Ecosystems Mission Area, Forest and Rangeland Ecosystem Science Center

Non-USGS Publications**

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Science and Products