BirdAnalyst
Species · BCR 5 · BBS 2026 Release · 1966–2025

Black-legged Kittiwake In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestWetland birds

Black-legged Kittiwake in Northern Pacific Rainforest has fallen sharply: down 53% on the route-weighted index since 1984.

-53%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 →
21YearsYears 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 fallen sharply in Northern Pacific Rainforest: down 53% 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 fall about 55% by 2030 — from 0.13 in 2025 to a central estimate of 0.06 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±1048.4%, with 100% of held-out values landing inside the 95% band.

-55%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 →
0.06Projected 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 →
0.00–1.595% 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 →
±1048.4%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 fall about 55% by 2030 — from 0.13 in 2025 to a central estimate of 0.06 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±1048.4%, with 100% of held-out values landing inside the 95% band.19702030
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 →
20260.090.001.6
20270.090.001.6
20280.080.001.6
20290.070.001.6
20300.060.001.5

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 →
YakutatALASKA92025
TaholahWASHINGTON41970
Mitkof IsleALASKA32003
CordovaALASKA22022
SewardALASKA11984
JuneauALASKA11996
HainesALASKA11996

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