BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Black Tern In Northern Rockies

All regionsNorthern RockiesWetland birds

Black Tern in Northern Rockies has collapsed: down 78% on the route-weighted index since 1971.

-78%Since 1971
15Routes In Region
49Years

Notable Signals

long arc declinecomputed index

Black Tern has collapsed in Northern Rockies: down 78% on the route-weighted index since 1971.

Forecast

If the recent trend holds, Black Tern in Northern Rockies is projected to stay roughly flat through 2029, near 0.13 (95% range 0.00–0.43). A 5-year backtest shows a typical error of ±826%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029
0.13Projected 2029 index
0.00–0.4395% range
±826%Backtest error
19682029
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
20250.130.000.43
20260.130.000.43
20270.130.000.43
20280.130.000.43
20290.130.000.43

Routes In Northern Rockies

Routes recording Black Tern in Northern Rockies.
KalispellMONTANA72018
NaplesIDAHO62022
GeboWYOMING61993
St MaryMONTANA32002
Pablo Res.MONTANA22017
GlenMONTANA21978
Twin LakesWASHINGTON22010
CurlewWASHINGTON21992
ArleeMONTANA11984
AugustaMONTANA11985
Mount VernonOREGON12009
RandolphUTAH12024
Neponset ResUTAH12004
ChewelahWASHINGTON12012
Green RiverWYOMING11982

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