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Species · Pennsylvania · BBS 2025 Release · 1966–2024

Hooded Warbler Population Trend in Pennsylvania

All statesForest birds

Hooded Warbler in Pennsylvania has surged: up 720% on the route-weighted index since 1968.

+720%Since 1968TrendPercent 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 →
105Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Hooded Warbler Trends in PennsylvaniaNotable 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 →

Hooded Warbler has surged in Pennsylvania: up 720% on the route-weighted index since 1968.

Hooded Warbler Population Forecast in Pennsylvania

If the recent trend holds, Hooded Warbler in Pennsylvania is projected to rise about 15% by 2029 — from 2.8 in 2024 to a central estimate of 3.2 (95% range 2.7–3.7). A 5-year backtest shows a typical error of ±13.9%, with 60% of held-out values landing inside the 95% band.

+15%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 →
3.2Projected 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 →
2.7–3.795% 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 →
±13.9%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, Hooded Warbler in Pennsylvania is projected to rise about 15% by 2029 — from 2.8 in 2024 to a central estimate of 3.2 (95% range 2.7–3.7). A 5-year backtest shows a typical error of ±13.9%, with 60% of held-out values landing inside the 95% band.19662029
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 →
20253.02.53.5
20263.02.53.5
20273.12.63.6
20283.12.63.6
20293.22.73.7

Hooded Warbler Survey Routes in Pennsylvania

Routes recording Hooded Warbler in Pennsylvania.
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 →
Broad Mtn.3620241993
Tussey Mtn.2720241993
Mill Run2220241978
Rothrock Sf1720191992
Roulette 21620242022
Landisburg1420241978
Odin1120241991
Roulette1120211993
Ansonia1020242002
Harrisville920231996
Duboistown820241987
N Washington720241967
N Pine Grove720241969
Eldred720221981
Laurel Hill720241978
Sigel620241981
Parkwood620241983
Kittanning620241975
Clear Spring620242002
Harmonsburg520231984
Ramsey520231995
Carsonville520231993
Normalville519701966
Whig Hill420241967
Margaret420241978

Hooded Warbler Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianakentuckylouisianamarylandmassachusettsmichiganmississippimissourinew-jerseynew-yorknorth-carolinaohiooklahomarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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