Tricolored Blackbird Portal

From 25 - 27 April, 2008 over 145 volunteer observers participated in the 2008 Tricolored Blackbird Statewide Survey. Survey participants searched for breeding colonies and aggregations of birds in 35 counties, from San Diego county in the south to Shasta county in the north. As expected, the largest colonies were found in the San Joaquin Valley, with Kern, Tulare, and Merced counties accounting for 314,936 of the total of 395,321 (79.7%) birds seen. The 2008 results compare favorably with recent Survey results (200,000 birds in 2000, 260,000 birds in 2005).

Although a stable or increasing population trend for the Central Valley is suggested by these results, the bird has nearly been eliminated from Central Valley counties where it was formerly common; for example, despite intensive survey efforts, no colonies were observed in San Joaquin county, the only colony known from Madera county was located in a silage field and destroyed by harvest prior to the Survey, and only one colony each was observed in Kings county (and this on a Naval Air Station) and Solano county.

Perhaps even more worrisome is the number of birds reported from southern California, where only 5,487 birds were counted in four counties (Los Angeles, 1270; Riverside, 2150; San Bernardino, 700; San Diego, 1367; the tricolor is now absent from Ventura and Orange counties as a breeding species and has historically been an infrequent visitor to Imperial county). A century ago, the tricolored blackbird was reported to be the most abundant bird species in the San Diego to Los Angeles region of coastal southern California and was extremely common north to Santa Barbara.

We thank the 2008 Statewide Survey participants for their hard work and Rodd Kelsey of Audubon California for effectively coordinating this year's Survey.