Tricolored Blackbird - Monitoring [ds98]

Observations recorded during breeding season surveys for tricolored blackbirds conducted across their range in California primarily during the 1994, 1995, 1996, 1997, and 1999 breeding seasons. Records contain observations made either 1) during an organized statewide survey constrained by short survey windows to reduce the possibility of duplicative counting or 2) outside of these prescribed survey windows and therefore not considered for population size estimates or other derived analyses. Observations recorded from April 20 to 26, 1994; April 19 to 25, 1995; April 24 to 30, 1996; April 23 to 29, 1997; April 18 to 24, 1999 (inclusive) should be considered part of the statewide coordinated survey and colony size estimates for observations made during these periods were considered in the overall population estimate for each year (see "Tricolored Blackbird Status Update and Management Guidelines", Beedy and Hamilton 1997, available at http://www.dfg.ca.gov/hcpb/info/bm_research/bm_pdfrpts/97_07.pdf for additional information). Organized surveys conducted during the time frames described above utilized highly skilled volunteers from natural resource conservation and management agencies, universities and state colleges, and private bird research and conservation organizations. Most large (>10,000) colonies initially detected by a volunteer observer, and for which an initial population estimate was calculated, were visited by a trained and knowledgable Tricolored Blackbird expert to validate the initial estimate. In some cases, research participants conducted post-fledging nest counts to assist in calibrating colony size estimates. The 1994 survey was organized by California Audubon and cosponsored by the California Department of Fish and Game and the U.S. Fish and Wildlife Service. The remaining surveys were organized by the California Department of Fish and Game. The majority of observation from all years are from the central valley and western desert regions. Each record in the database represents a single colony observation by an observer at a given place and time. Record attributes describe the observers assessment of the breeding status of the colony, a colony size estimate, the observers name, and other information.

Recognition that the data set was and created and provided by the California Department of Fish and Wildlife from information provided the Department, the U.S. Fish and Wildlife Service, and by numerous cooperators.

Disclaimer: The State makes no claims, promises, or guarantees about the accuracy, completeness, reliability, or adequacy of these data and expressly disclaims liability for errors and omissions in these data. No warranty of any kind, implied, expressed, or statutory, including but not limited to the warranties of non-infringement of third party rights, title, merchantability, fitness for a particular purpose, and freedom from computer virus, is given with respect to these data.