Species · Colorado · BBS 2025 Release · 1966–2024

Wilson's Phalarope Population Trend in Colorado

Wilson's Phalarope in Colorado has fallen sharply: down 74% on the route-weighted index since 1973.

-74%Since 1973
43Routes In State
49Years

Notable Wilson's Phalarope Trends in Colorado

long arc declinecomputed index

Wilson's Phalarope has fallen sharply in Colorado: down 74% on the route-weighted index since 1973.

Wilson's Phalarope Population Forecast in Colorado

If the recent trend holds, Wilson's Phalarope in Colorado is projected to rise about 178% by 2028 — from 0.08 in 2023 to a central estimate of 0.23 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±543%, with 100% of held-out values landing inside the 95% band.

+178%Change by 2028
0.23Projected 2028 index
0.001.195% range
±543%Backtest error
19682028
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
20240.250.001.1
20250.240.001.1
20260.240.001.1
20270.230.001.1
20280.230.001.1

Wilson's Phalarope Survey Routes in Colorado

Routes recording Wilson's Phalarope in Colorado.
Nunn2920142010
Briggsdale1019961989
Julesburg820212004
Pritchett720022002
Alamosa620231988
Parlin419891968
Karval420172001
Amherst419951995
Stillwater Pass420032001
Buford320091985
Kiowa320002000
Doyleville320051988
Edler320142014
Lamar220232021
Rio Grnds Rs219921992
Lay220191996
Bennett220012001
Powderhorn219951995
Stoneham220211998
Cortez219971988
Maybell120181974
Fleming120151987
Last Chance119831983
Colona119881988
Moffat120211970

Wilson's Phalarope Population Trend in Other States

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