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Species · Alaska · BBS 2025 Release · 1966–2024

Black Oystercatcher Population Trend in Alaska

All statesShorebirds

Black Oystercatcher in Alaska has fallen sharply: down 74% on the route-weighted index since 1986.

-74%Since 1986TrendPercent 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 →
5Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
32YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black Oystercatcher Trends in AlaskaNotable 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 Oystercatcher has fallen sharply in Alaska: down 73% on the route-weighted index since 1986.

Black Oystercatcher Population Forecast in Alaska

If the recent trend holds, Black Oystercatcher in Alaska is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±93.4%, 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 →
0.01Projected 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 →
0.00–0.2595% 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 →
±93.4%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 Oystercatcher in Alaska is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±93.4%, with 100% of held-out values landing inside the 95% band.19832029
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 →
20250.030.000.26
20260.020.000.26
20270.020.000.26
20280.010.000.25
20290.010.000.25

Black Oystercatcher Survey Routes in Alaska

Routes recording Black Oystercatcher in Alaska.
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 →
Kodiak919831983
Sitka (Short)319911985
Adak319951983
Kodiak 2220241985
Chiniak120241985

Black Oystercatcher Population Trend in Other States

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