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

Merlin Population Trend in Wisconsin

All statesGeneralists

Merlin in Wisconsin has surged: up 108% on the route-weighted index since 1995.

+108%Since 1995TrendPercent 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 →
27Routes 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 →
23YearsYears 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 WisconsinNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Merlin in Wisconsin. See the full index history below.

Merlin Population Forecast in Wisconsin

If the recent trend holds, Merlin in Wisconsin is projected to stay roughly flat through 2029, near 0.05 (95% range 0.01–0.09). A 5-year backtest shows a typical error of ±47.3%, with 60% 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 →
0.05Projected 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 →
0.01–0.0995% 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 →
±47.3%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 Wisconsin is projected to stay roughly flat through 2029, near 0.05 (95% range 0.01–0.09). A 5-year backtest shows a typical error of ±47.3%, with 60% 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 →
20250.040.000.09
20260.040.000.09
20270.050.010.09
20280.050.010.09
20290.050.010.09

Merlin Survey Routes in Wisconsin

Routes recording Merlin in Wisconsin.
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 →
Irma320102010
Chaffey220222006
Shanagolden220071995
Eagle River220212013
Manawa220212021
Amnicon Falls220232023
Manitowoc220142012
Cavour220192016
Iron River120231993
Grand View120182013
Bayfield120232012
Land O Lakes120162016
Couderay120072007
Phillips120191974
Merrill120242024
Wausaukee120192019
Washington I120222007
Gilmanton120212021
Trempealeau120212021
Cadott120152015
Mellen120242024
Clintonville120232023
Conover120222017
Bashaw120112010
Rhinelander120142014

Merlin Population Trend in Other States

alaskaidahomainemassachusettsmichiganminnesotamontananebraskanew-hampshirenew-yorknorth-dakotaoregonpennsylvaniasouth-dakotavermontvirginiawashingtonwest-virginiawyoming

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