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

Lesser Scaup In Northern Rockies

All regionsNorthern RockiesWaterfowl

Lesser Scaup in Northern Rockies has surged: up 82% on the route-weighted index since 1977.

+82%Since 1977
58Routes In Region
49Years

Notable Signals

long arc increasecomputed index

Lesser Scaup has surged in Northern Rockies: up 82% on the route-weighted index since 1977.

Forecast

If the recent trend holds, Lesser Scaup in Northern Rockies is projected to rise about 297% by 2029 — from 0.18 in 2024 to a central estimate of 0.73 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±233.6%, with 100% of held-out values landing inside the 95% band.

+297%Change by 2029
0.73Projected 2029 index
0.00–2.095% range
±233.6%Backtest error
19702029
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
20250.740.002.0
20260.740.002.0
20270.730.002.0
20280.730.002.0
20290.730.002.0

Routes In Northern Rockies

Routes recording Lesser Scaup in Northern Rockies.
Hayden ValWYOMING291986
MammothWYOMING132024
ClarkWYOMING122001
YellowstoneWYOMING112022
Rock RiverWYOMING82022
Clover CreekOREGON61997
Willow Creek 2MONTANA52006
Neponset ResUTAH52017
CentervilleIDAHO42010
Sawtooth City 2IDAHO42017
St MaryMONTANA41997
AugustaMONTANA42024
East Glacier ParkMONTANA42019
Hunter PeakWYOMING42024
SeedskadeeWYOMING41997
NaplesIDAHO31977
FontenelleWYOMING31987
ErvayWYOMING32018
Crazy WomanWYOMING32010
Fiddler LkWYOMING32011
CascadeIDAHO21978
CabartonIDAHO22022
Crane CreekIDAHO21994
BeaverheadMONTANA22012
Red RockMONTANA22021

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