BirdAnalyst
Species · South Dakota · BBS 2025 Release · 1966–2024

MacGillivray's Warbler Population Trend in South Dakota

All statesForest birds

MacGillivray's Warbler in South Dakota has held roughly steady: up 2% on the route-weighted index since 1993.

+2%Since 1993TrendPercent 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 →
10Routes 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 →
30YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable MacGillivray's Warbler Trends in South DakotaNotable 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 MacGillivray's Warbler in South Dakota. See the full index history below.

MacGillivray's Warbler Population Forecast in South Dakota

If the recent trend holds, MacGillivray's Warbler in South Dakota is projected to fall about 70% by 2029 — from 0.18 in 2024 to a central estimate of 0.05 (95% range 0.00–0.28). A 5-year backtest shows a typical error of ±48.2%, with 100% of held-out values landing inside the 95% band.

-70%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 →
0.05Projected 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 →
0.00–0.2895% 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 →
±48.2%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, MacGillivray's Warbler in South Dakota is projected to fall about 70% by 2029 — from 0.18 in 2024 to a central estimate of 0.05 (95% range 0.00–0.28). A 5-year backtest shows a typical error of ±48.2%, with 100% of held-out values landing inside the 95% band.19812029
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 →
20250.070.000.29
20260.060.000.29
20270.060.000.29
20280.060.000.28
20290.050.000.28

MacGillivray's Warbler Survey Routes in South Dakota

Routes recording MacGillivray's Warbler in South Dakota.
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 →
Long Draw420241994
Rochford320181996
Englewood220211994
Norbeck220001993
Hazelrodt120011993
Lightning Cr120091992
Hill City120131996
Black Fox120171994
Roubaix Lk119811981
Silver City120021992

MacGillivray's Warbler Population Trend in Other States

alaskaarizonacaliforniacoloradoidahomontananevadanew-mexicooregontexasutahwashingtonwyoming

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