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

Connecticut Warbler Population Trend in Minnesota

All statesForest birds

Connecticut Warbler in Minnesota has declined: down 32% on the route-weighted index since 1970.

-32%Since 1970TrendPercent 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 →
31Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Connecticut Warbler Trends in MinnesotaNotable 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 Connecticut Warbler in Minnesota. See the full index history below.

Connecticut Warbler Population Forecast in Minnesota

If the recent trend holds, Connecticut Warbler in Minnesota is projected to rise about 173% by 2029 — from 0.07 in 2024 to a central estimate of 0.20 (95% range 0.00–0.49). A 5-year backtest shows a typical error of ±226.6%, with 100% of held-out values landing inside the 95% band.

+173%Change 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 →
0.20Projected 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 →
0.00–0.4995% 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 →
±226.6%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, Connecticut Warbler in Minnesota is projected to rise about 173% by 2029 — from 0.07 in 2024 to a central estimate of 0.20 (95% range 0.00–0.49). A 5-year backtest shows a typical error of ±226.6%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.210.000.51
20260.210.000.50
20270.200.000.50
20280.200.000.50
20290.200.000.49

Connecticut Warbler Survey Routes in Minnesota

Routes recording Connecticut Warbler in Minnesota.
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 →
Waskish420191978
Red Lake420241995
Grygla319871987
Mille Lacs219961996
Floodwood220121978
Crane Lake220031969
Blackduck220042004
Greenbush220162016
Cass Lake119931984
Nebish120191987
Cromwell120191967
Backus119861971
Pine River119791979
Evergreen119831983
Hovland119951976
Lockport119831967
Sawbill Lndg120181973
Hart Lake120101972
Island Lake120161979
Cohasset119911974
Sherry Lake120211969
Bena119771977
Debs119921987
Little Fork120191969
Lude120141978

Connecticut Warbler Population Trend in Other States

michigannew-yorkwisconsin

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