BirdAnalyst
Guild

Seabirds

7 species tracked. As a group, seabirds are +84%Guild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology → since 1968.

Guild SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for seabirds. See the full index history below.

Seabirds Population Forecast

If the recent trend holds, Seabirds as a group is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±34%, 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 →
0.00–0.1095% 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 →
±34%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, Seabirds as a group is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±34%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.010.000.10
20260.010.000.10
20270.010.000.10
20280.010.000.10
20290.010.000.10

Seabirds By State

Seabirds group trend by state.
Guild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology →
California-94%3
Washington-72%3
Alaska-16%4

Member Species

Species in the Seabirds guild.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →
Common MurreAlcidae-97%1974
Magnificent FrigatebirdFregatidae-80%1968
Parasitic JaegerStercorariidae-73%1985
Rhinoceros AukletAlcidae-1%1976
Pigeon GuillemotAlcidae+17%1973
Long-tailed JaegerStercorariidae+829%1986
Marbled MurreletAlcidae31×1977