BirdAnalyst
Species · Wyoming · BBS 2025 Release · 1966–2024

Merlin Population Trend in Wyoming

All statesGeneralists

Merlin in Wyoming has fallen sharply: down 63% on the route-weighted index since 1977.

-63%Since 1977TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
21Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
25YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Merlin Trends in WyomingNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Merlin has fallen sharply in Wyoming: down 63% on the route-weighted index since 1977.

Merlin Population Forecast in Wyoming

If the recent trend holds, Merlin in Wyoming is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.06). A 5-year backtest shows a typical error of ±174.1%, with 40% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.01Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0695% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±174.1%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Merlin in Wyoming is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.06). A 5-year backtest shows a typical error of ±174.1%, with 40% of held-out values landing inside the 95% band.19742029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.010.000.07
20260.010.000.07
20270.010.000.07
20280.010.000.07
20290.010.000.06

Merlin Survey Routes in Wyoming

Routes recording Merlin in Wyoming.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Bill219991999
Seely 2220032003
Shawnee220192019
Green River219821977
Cody120121983
Basin119741974
Sundance120072007
Bear Creek119891989
Gvnt Valley120122011
Patrick Draw119761976
Hunter Peak119971992
Tensleep120112011
Seely120002000
Wilson119791979
Gebo119831983
Big Sandy119901990
Shirley119921992
Lusk120182018
Mtn View120242024
Kaycee120242024
Welch120192019

Merlin Population Trend in Other States

alaskaidahomainemassachusettsmichiganminnesotamontananebraskanew-hampshirenew-yorknorth-dakotaoregonpennsylvaniasouth-dakotavermontvirginiawashingtonwest-virginiawisconsin

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