BirdAnalyst
Guild · Pennsylvania · BBS 2026 Release · 1966–2025

Generalists In Pennsylvania

All statesPennsylvania

11 species in this guild. As a group they are -54%Guild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology → since 1968.

Guild SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

guild collapsecomputed 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 →

Generalists as a group have fallen sharply in Pennsylvania, down 54% since 1968.

Generalists In Pennsylvania Population Forecast

If the recent trend holds, Generalists in Pennsylvania is projected to stay roughly flat through 2030, near 16 (95% range 9.9–21). A 5-year backtest shows a typical error of ±5.1%, with 100% of held-out values landing inside the 95% band.

-3%Change by 2030TrendPercent 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 →
16Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
9.9–2195% 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 →
±5.1%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, Generalists in Pennsylvania is projected to stay roughly flat through 2030, near 16 (95% range 9.9–21). A 5-year backtest shows a typical error of ±5.1%, with 100% of held-out values landing inside the 95% band.19662030
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 →
2026171123
2027171122
2028161022
2029161022
2030169.921

Member Species In Pennsylvania

Generalists species in Pennsylvania.
TrendPercent 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 →
Common GrackleIcteridae-75%
House SparrowPasseridae-73%
Rock PigeonColumbidae-59%
Brown-headed CowbirdIcteridae-44%
European StarlingSturnidae-37%
American CrowCorvidae-10%
Northern MockingbirdMimidae+34%
Mourning DoveColumbidae+102%
Fish CrowCorvidae+226%
Common RavenCorvidae22×
House FinchFringillidae68×

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.