BirdAnalyst
BBS Route · California · BCR 32

San Ysidro Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 99 species recorded across 18 survey years, no longer active.

99Species RecordedSpecies recordedDistinct species detected on standard-protocol BBS runs here across all years on record — a measure of survey breadth, not a complete checklist.Full methodology →
18Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
1973–2019Span
10Observers

Bird Species Found on California San Ysidro

Top 40 of 99 species by most recent count. Each links to its species trend.

Species recorded on the San Ysidro route.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →History
House FinchFringillidae932019-65%1975
Cliff SwallowHirundinidae832019+52%1975
House SparrowPasseridae752019-77%1975
American CrowCorvidae422019+571%1991
Tricolored BlackbirdIcteridae301986+25%1977
Lesser GoldfinchFringillidae282019+190%1986
Northern MockingbirdMimidae222019-64%1975
California TowheePasserellidae202019+25%1975
Western GrebePodicipedidae161990n/an/a
Rock PigeonColumbidae152019-81%1975
BushtitAegithalidae152019+39%1986
Anna's HummingbirdTrochilidae142019+200%1986
Hooded OrioleIcteridae132019+317%1975
Mourning DoveColumbidae122019-79%1975
Brewer's BlackbirdIcteridae112004-90%1975
White-throated SwiftApodidae102019+400%1988
Cassin's KingbirdTyrannidae102019+343%1990
California GullLaridae91990+71%1988
Yellow WarblerParulidae92019+106%2003
Yellow-breasted ChatIcteriidae82019+100%1986
Western BluebirdTurdidae72019+600%2013
Common RavenCorvidae62018-48%1989
Orange-crowned WarblerParulidae62019+125%2004
Common YellowthroatParulidae52019+200%1975
Red-shouldered HawkAccipitridae52019+160%1989
Black PhoebeTyrannidae52019+7%1989
Bell's VireoVireonidae52019+100%2004
Eurasian Collared-DoveColumbidae52019+0%2017
KilldeerCharadriidae42004-12%1977
Western KingbirdTyrannidae42003+50%1986
European StarlingSturnidae42019-97%1975
Savannah SparrowPasserellidae41976-67%1973
WrentitSylviidae42019+117%1986
American RobinTurdidae42004+33%1986
Nuttall's WoodpeckerPicidae42019+14%2004
Western GullLaridae32019-90%1976
Least TernLaridae31992+50%1973
Burrowing OwlStrigidae31976+0%1974
Brown-headed CowbirdIcteridae32004-63%1977
Bewick's WrenTroglodytidae32019+200%1975

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. A route is a sample, not a census.