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Species · BCR 5 · BBS 2025 Release · 1966–2024

Black-legged Kittiwake In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestWetland birds

Black-legged Kittiwake in Northern Pacific Rainforest has collapsed: down 81% on the route-weighted index since 1984.

-81%Since 1984TrendPercent 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 →
7Routes 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 →
20YearsYears 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 →

Black-legged Kittiwake has collapsed in Northern Pacific Rainforest: down 81% on the route-weighted index since 1984.

Black-legged Kittiwake In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Black-legged Kittiwake in Northern Pacific Rainforest is projected to stay roughly flat through 2029, near 0.06 (95% range 0.00–1.6). A 5-year backtest shows a typical error of ±1322.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent 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 →
0.06Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.695% 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 →
±1322.4%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, Black-legged Kittiwake in Northern Pacific Rainforest is projected to stay roughly flat through 2029, near 0.06 (95% range 0.00–1.6). A 5-year backtest shows a typical error of ±1322.4%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.100.001.6
20260.090.001.6
20270.080.001.6
20280.070.001.6
20290.060.001.6

Routes In Northern Pacific Rainforest

Routes recording Black-legged Kittiwake in Northern Pacific Rainforest.
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 →
TaholahWASHINGTON41970
Mitkof IsleALASKA32003
CordovaALASKA22022
YakutatALASKA22024
SewardALASKA11984
JuneauALASKA11996
HainesALASKA11996

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