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Species · Wyoming · BBS 2025 Release · 1966–2024

MacGillivray's Warbler Population Trend in Wyoming

All statesForest birds

MacGillivray's Warbler in Wyoming has surged: up 110% on the route-weighted index since 1970.

+110%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 →
43Routes 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 →
55YearsYears 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 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 increasecomputed 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 →

MacGillivray's Warbler has surged in Wyoming: up 110% on the route-weighted index since 1970.

MacGillivray's Warbler Population Forecast in Wyoming

If the recent trend holds, MacGillivray's Warbler in Wyoming is projected to fall about 18% by 2029 — from 0.97 in 2024 to a central estimate of 0.79 (95% range 0.30–1.3). A 5-year backtest shows a typical error of ±11.8%, with 100% of held-out values landing inside the 95% band.

-18%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 →
0.79Projected 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 →
0.30–1.395% 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 →
±11.8%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 Wyoming is projected to fall about 18% by 2029 — from 0.97 in 2024 to a central estimate of 0.79 (95% range 0.30–1.3). A 5-year backtest shows a typical error of ±11.8%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.770.281.3
20260.770.281.3
20270.780.291.3
20280.790.291.3
20290.790.301.3

MacGillivray's Warbler Survey Routes in Wyoming

Routes recording MacGillivray's Warbler 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 →
Alpine2920241979
Colter Bay1219981968
Wilson1220241980
Moskee1120011980
Buckskin Mtn920211980
Moskee 3820242022
Colter Bay 2720242019
Hunter Peak620241982
Moose620241976
Sybille Cyn519801980
Moskee 2520192002
Sundance420241976
Soda Lake420241980
Seedskadee319971997
Moran320162003
Green River319821977
Ne Entrance220191989
Yellowstone220112000
Savery219951989
Horse Creek220241986
Fiddler Lk220241987
Warbonnet220231994
Savery 2220242007
Cody120241993
Dubois120241968

MacGillivray's Warbler Population Trend in Other States

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