BirdAnalyst
Species · BCR 2 · BBS 2025 Release · 1966–2024

American Dipper In BCR 2

All regionsBCR 2Generalists

American Dipper in BCR 2 has collapsed: down 79% on the route-weighted index since 1988.

-79%Since 1988TrendPercent 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 →
8Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
15YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

American Dipper has collapsed in BCR 2: down 79% on the route-weighted index since 1988.

Routes In BCR 2

Routes recording American Dipper in BCR 2.
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 →
KodiakALASKA11983
ChiniakALASKA11988
DillinghamALASKA12001
Cold BayALASKA12023
Kodiak 2ALASKA11994
CouncilALASKA12017
Togiak RiverALASKA11999
Kanektok RivALASKA12001

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.