BirdAnalyst
Species · BCR 2 · BBS 2025 Release · 1966–2024

Aleutian Tern In BCR 2

All regionsBCR 2Wetland birds

Aleutian Tern in BCR 2 has fallen sharply: down 73% on the route-weighted index since 1985.

-73%Since 1985
10Routes In Region
37Years

Notable Signals

long arc declinecomputed index

Aleutian Tern has fallen sharply in BCR 2: down 73% on the route-weighted index since 1985.

Forecast

If the recent trend holds, Aleutian Tern in BCR 2 is projected to fall about 49% by 2029 — from 2.6 in 2024 to a central estimate of 1.3 (95% range 0.00–7.7). A 5-year backtest shows a typical error of ±352.4%, with 100% of held-out values landing inside the 95% band.

-49%Change by 2029
1.3Projected 2029 index
0.00–7.795% range
±352.4%Backtest error
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 index95% low95% high
20251.50.008.0
20261.50.007.9
20271.40.007.9
20281.40.007.8
20291.30.007.7

Routes In BCR 2

Routes recording Aleutian Tern in BCR 2.
King SalmonALASKA212024
KodiakALASKA191984
ChiniakALASKA62015
Kotzebue (Short)ALASKA61986
Cape NomeALASKA42019
Cold BayALASKA22024
Kodiak 2ALASKA22019
CouncilALASKA12006
KotzebueALASKA12010
Cold Bay (Short)ALASKA11990

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