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Riparian Area Raptors - Sierra Nevada Foothills [ds294]

Metadata Updated: November 27, 2024

These data are point locations where hawks and owls (raptors) were detected during playback surveys conducted between 28 March 2005 and 21 July 2005 along 36 randomly selected watercourses in the foothills of the Sierra Nevada Mountain Range. These data represent 260 positive responses for several species of hawks and owls to the playback surveys. This study was done by the North Central Region of the California Department of Fish and Game with support from the Resource Assessment Program. These data represent the point locations where individual hawks and owls were detected based on geographic algorithms using estimated distances and compass bearings from fixed points along public roads. Methodology: Playback surveys using MP3 players and battery-powered speakers were done to elicit vocal or behavioral responses from hawks and owls from fixed points along public roads in the foothills of the Sierra Nevada. The surveys were done along 36 randomly selected watercourses, and one or three surveys were done at the points between March and July 2005. Seventeen watercourses had one survey while 19 watercourses had three surveys. Survey periods were (1) March to mid-April, (2) late April to late May, and (3) June to July. Watercourses with one survey were surveyed during the March to mid-April period; watercourses with one survey were dropped from the study after the first survey due to logistic and manpower constraints. Each watercourse had 3-5 fixed points that were between 500-1,000 meters apart to ensure spatial independence. Hawk surveys were conducted between 8:00 am and 5:00 pm, while owl surveys were conducted between 8:30 pm and 4:15 am. Playback surveys were done with fixed sequences of species calls as follows: (1) for hawks, sharp-shinned hawks, Coopers hawks, and red-shouldered hawks; and (2) for owls, flammulated owl (starting in May), northern saw-whet owl, northern pygmy-owl, western screech-owl, long-eared owl, and great-horned owl. No calls were done for red-tailed hawks, osprey, Swainsons hawks, or barn owls which were detected during the surveys and included in these data. The duration of the playbacks for each species consisted of a 1-minute silent period, a 4-minute playback period with 4 repeated sequences of 30 seconds of vocalizations followed by 30 seconds of silence, and a 1-minute silent period. The speaker initially faced North, and was then rotated South, West, and East with successive 30-second playback/30-second silence periods. Detected animals were visually or aurally located and identified. Laser rangefinders were used to estimate distances, while compasses were used to derive compass bearings. Habitats of detected animals were determined from field observations during the day for hawks or from aerial photographs with owls based on knowledge of field conditions at the fixed points. A GIS algorithm was used to locate the estimated field locations based on the estimated distances and compass bearings, and then habitats were verified with aerial photographs. The sex and age of each detected individual was determined if possible, and observers rated the confidence of their determination of the number of individuals, species type, sex and age of each detection.

Access & Use Information

Public: This dataset is intended for public access and use. Non-Federal: This dataset is covered by different Terms of Use than Data.gov. License: See this page for license information.

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Dates

Metadata Created Date September 15, 2023
Metadata Updated Date November 27, 2024

Metadata Source

Harvested from State of California

Additional Metadata

Resource Type Dataset
Metadata Created Date September 15, 2023
Metadata Updated Date November 27, 2024
Publisher California Department of Fish and Wildlife
Maintainer
Identifier b0e35245-468c-4a1b-8d41-9e6e0c92ce1b
Data First Published 2020-02-27T17:34:56.000Z
Data Last Modified 2020-02-27T17:35:28.712Z
Category Natural Resources
Public Access Level public
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 8df87cee-2ce8-4442-b636-9ba42b21a8f3
Harvest Source Id 3ba8a0c1-5dc2-4897-940f-81922d3cf8bc
Harvest Source Title State of California
License http://www.opendefinition.org/licenses/cc-by
Source Datajson Identifier True
Source Hash 98c5798743f20b812da6b2e4eee80516bed2f8eca8d01a463d1ccba102548774
Source Schema Version 1.1

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