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

Ruby-throated Hummingbird Population Trend in Pennsylvania

All statesGeneralists

Ruby-throated Hummingbird in Pennsylvania has surged: up 404% on the route-weighted index since 1968.

+404%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 →
130Routes 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 Ruby-throated Hummingbird 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 →

Ruby-throated Hummingbird has surged in Pennsylvania: up 404% on the route-weighted index since 1968.

Ruby-throated Hummingbird Population Forecast in Pennsylvania

If the recent trend holds, Ruby-throated Hummingbird in Pennsylvania is projected to rise about 93% by 2029 — from 0.46 in 2024 to a central estimate of 0.89 (95% range 0.52–1.3). A 5-year backtest shows a typical error of ±63.5%, with 60% of held-out values landing inside the 95% band.

+93%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 →
0.89Projected 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 →
0.52–1.395% 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 →
±63.5%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, Ruby-throated Hummingbird in Pennsylvania is projected to rise about 93% by 2029 — from 0.46 in 2024 to a central estimate of 0.89 (95% range 0.52–1.3). A 5-year backtest shows a typical error of ±63.5%, 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 →
20250.840.481.2
20260.860.491.2
20270.870.501.2
20280.880.511.2
20290.890.521.3

Ruby-throated Hummingbird Survey Routes in Pennsylvania

Routes recording Ruby-throated Hummingbird 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 →
Kaylor420211967
Ferris Crnrs320211971
Russell City320231979
Ridgway320141996
Rasselas320212001
Marsh Hill320171983
Greentown320241979
Waterstreet320241974
Pine Gr Mill320211983
Ansonia320242004
Harmonsburg220231972
Whig Hill220141970
Teepleville220231966
Lynch220221987
Odin220241975
Betula220221987
Eldred220221973
Little Marsh220231973
Honesdale220241986
Starlight219991970
Beaver220231972
Duvall220141974
Sardis219731970
Shelocta220241981
Naginey220221970

Ruby-throated Hummingbird Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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