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

Common Loon In BCR 2

All regionsBCR 2Wetland birds

Common Loon in BCR 2 has surged: up 83% on the route-weighted index since 1988.

+83%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 →
14Routes 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 →
37YearsYears 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 increasecomputed 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 →

Common Loon has surged in BCR 2: up 82% on the route-weighted index since 1988.

Common Loon In BCR 2 Population Forecast

If the recent trend holds, Common Loon in BCR 2 is projected to rise about 62% by 2030 — from 0.33 in 2025 to a central estimate of 0.54 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±47.4%, with 80% of held-out values landing inside the 95% band.

+62%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 →
0.54Projected 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 →
0.00–1.395% 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 →
±47.4%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, Common Loon in BCR 2 is projected to rise about 62% by 2030 — from 0.33 in 2025 to a central estimate of 0.54 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±47.4%, with 80% of held-out values landing inside the 95% band.19852030
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 →
20260.550.001.3
20270.550.001.3
20280.550.001.3
20290.540.001.3
20300.540.001.3

Routes In BCR 2

Routes recording Common Loon 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 →
Cape NomeALASKA92024
DillinghamALASKA52019
Cold Bay (Short)ALASKA41992
Katmai N.P.ALASKA12019
ChiniakALASKA12024
Cold BayALASKA12025
King SalmonALASKA12025
Kodiak 2ALASKA12024
CouncilALASKA12024
NomeALASKA12003
St. Mary'SALASKA12014
Togiak RiverALASKA12005
Gweek RiverALASKA11998
Goodnews BayALASKA12002

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