BirdAnalyst
Species · BCR 2 · BBS 2026 Release · 1966–2025

Bank Swallow In BCR 2

All regionsBCR 2Aerial insectivores

Bank Swallow in BCR 2 has fallen sharply: down 66% on the route-weighted index since 1985.

-66%Since 1985TrendPercent 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 →
22Routes 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 →
42YearsYears 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 →

Bank Swallow has fallen sharply in BCR 2: down 66% on the route-weighted index since 1985.

Bank Swallow In BCR 2 Population Forecast

If the recent trend holds, Bank Swallow in BCR 2 is projected to fall about 56% by 2030 — from 10 in 2025 to a central estimate of 4.4 (95% range 0.00–21). A 5-year backtest shows a typical error of ±51%, with 100% of held-out values landing inside the 95% band.

-56%Change by 2030TrendPercent 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 →
4.4Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–2195% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±51%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Bank Swallow in BCR 2 is projected to fall about 56% by 2030 — from 10 in 2025 to a central estimate of 4.4 (95% range 0.00–21). A 5-year backtest shows a typical error of ±51%, with 100% of held-out values landing inside the 95% band.19832030
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20265.50.0022
20275.30.0022
20285.00.0021
20294.70.0021
20304.40.0021

Routes In BCR 2

Routes recording Bank Swallow 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 →
Kanektok RivALASKA2232005
TupuknukALASKA1601995
Selawik (Short)ALASKA931987
Goodnews BayALASKA582005
Dillingham (Short)ALASKA561984
Gweek RiverALASKA322002
King SalmonALASKA232025
KodiakALASKA191984
Cold BayALASKA152025
Togiak RiverALASKA142005
KotzebueALASKA142025
ChiniakALASKA82025
Katmai N.P.ALASKA41996
Cold Bay (Short)ALASKA31992
Kotzebue (Short)ALASKA21994
DillinghamALASKA12001
Kodiak 2ALASKA12022
CouncilALASKA12005
NomeALASKA12023
Salmon LakeALASKA12023
St. Mary'SALASKA11996
Kugarak (Short)ALASKA11986

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.