File Geodatabase Feature Class
Tags
nesting colonies, San Bernardino County, Amador County, Solano County, Mariposa County, Sacramento Valley, tricolored blackbird, Kings County, environment, San Benito County, distribution, Santa Clara County, Glenn County, Monterey County, Contra Costa County, Colusa County, numbers, Merced County, Santa Barbara County, San Joaquin Valley, Siskiyou County, Alameda County, Central Valley, Ventura County, Tulare County, Riverside County, San Luis Obispo County, Fresno County, Yuba County, Humboldt County, Stanislaus County, Lake County, Santa Cruz County, breeding, Sacramento County, Calaveras County, Napa County, Yolo County, Los Angeles County, San Joaquin County, biota, Mendocino County, Placer County, location, Tuolumne County, California, Shasta County, Modoc County, Madera County, Butte County, Lassen County, San Diego County, Sonoma County, Sutter County, Tehama County, Kern County, Orange County
The database documents the number and location of breeding colonies of tricolored blackbirds. It can be used to display the known distribution of observations for this species, where nesting concentrations occur and have occurred in recent years, and the location of areas which habitually may support the majority of the breeding birds. *****The information in this data should be considered historical. For the most recent data on breeding locations please contact Neil Clipperton - Neil.Clipperton@wildlife.ca.gov.*****
These data come from observations of breeding tricolored blackbirds throughout their range in California. NAD27 coordinates are given in the data for each record. But, the shapefile is converted to NAD83 and projected using that datum in the BIOS viewer. For further information please see "Tricolored Blackbird Status Update and Management Guidelines," September, 1997, available at http://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=2920 . There are records from 1980 through 2000. However, less than 35 records are from prior to 1992. There are from 113 to 202 records per year from 1993 through 2000 except for considerably fewer records in 1993 and only four records from 1998. Major statewide surveys were conducted in 1994, organized by California Audubon, and in 1995, 1996, 1997 and 1999, cosponsored by the California Department of Fish and Wildlife and the U.S. Fish and Wildlife Service. These data do not include a survey organized by Point Reyes Bird Observatory in 2001. There are 1091 records of breeding tricolored blackbirds. A number of these records represent surveys of the same colony made in different years. These records are distributed across 48 counties and include 10 observations in the Klamath Basin of southern Oregon and a record from Baja California. However, the majority come from the Central Valley with a lesser number from central and south coast areas. The base data is maintained in a .dbf format database by the Wildlife and Habitat Data Analysis Branch at the California Department of Fish and Wildlife. Though there is a similar database of negative observations, that information is not included here. Each record contains information on the date of the observation, the estimated size of the breeding colony, the vegetation used by the nesting birds, and the location of the colony.
Gordon Gould - California Department of Fish and Wildlife Kevin Hunting - Wildlife Habitat and Data Analysis Branch, California Department of Fish and Wildlife
Recognition that the data set was created and provided by the Department from information provided by the California Department of Fish and Wildlife, the U.S. Fish and Wildlife Service, and by numerous cooperators.
Extent
| West | -124.257848 | East | -115.539418 |
| North | 42.394806 | South | 30.952592 |
| Maximum (zoomed in) | 1:5,000 |
| Minimum (zoomed out) | 1:150,000,000 |
Recognition that the data set was created and provided by the Department from information provided by the California Department of Fish and Wildlife, the U.S. Fish and Wildlife Service, and by numerous cooperators.