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

Trumpeter Swan In Northern Rockies

All regionsNorthern RockiesWaterfowl

Trumpeter Swan in Northern Rockies has collapsed: down 84% on the route-weighted index since 1975.

-84%Since 1975
22Routes In Region
43Years

Notable Signals

long arc declinecomputed index

Trumpeter Swan has collapsed in Northern Rockies: down 83% on the route-weighted index since 1975.

Forecast

If the recent trend holds, Trumpeter Swan in Northern Rockies is projected to fall about 100% by 2029 — from 0.19 in 2024 to a central estimate of 0.00 (95% range 0.00–0.64). A 5-year backtest shows a typical error of ±181.3%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.00–0.6495% range
±181.3%Backtest error
19732029
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
20250.000.000.64
20260.000.000.64
20270.000.000.64
20280.000.000.64
20290.000.000.64

Routes In Northern Rockies

Routes recording Trumpeter Swan in Northern Rockies.
FontenelleWYOMING172024
NaplesIDAHO82021
BeaverheadMONTANA42023
KalispellMONTANA22013
Red RockMONTANA22024
Inside RoadMONTANA22024
MammothWYOMING22024
AlpineWYOMING21998
RyegrassWYOMING22016
SeedskadeeWYOMING22016
Seedskadee 2WYOMING22024
AugustaMONTANA12021
Pablo Res.MONTANA12024
Clover CreekOREGON11996
RandolphUTAH12023
Ne EntranceWYOMING12018
Hunter PeakWYOMING12002
MooseWYOMING12021
BoulderWYOMING12023
Mtn ViewWYOMING12024
MoranWYOMING12016
YellowstoneWYOMING12021

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