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

Mute Swan Population Trend in Pennsylvania

All statesWaterfowl

Mute Swan in Pennsylvania has increased: up 47% on the route-weighted index since 1984.

+47%Since 1984TrendPercent 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 →
12Routes 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 →
27YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Mute Swan 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 →

No notable trend signals for Mute Swan in Pennsylvania. See the full index history below.

Mute Swan Population Forecast in Pennsylvania

If the recent trend holds, Mute Swan in Pennsylvania is projected to stay roughly flat through 2028, near 0.05 (95% range 0.00–0.11). A 5-year backtest shows a typical error of ±72.2%, with 100% of held-out values landing inside the 95% band.

+6%Change by 2028TrendPercent 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 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1195% 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 →
±72.2%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, Mute Swan in Pennsylvania is projected to stay roughly flat through 2028, near 0.05 (95% range 0.00–0.11). A 5-year backtest shows a typical error of ±72.2%, with 100% of held-out values landing inside the 95% band.19822028
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 →
20240.050.000.10
20250.050.000.10
20260.050.000.10
20270.050.000.11
20280.050.000.11

Mute Swan Survey Routes in Pennsylvania

Routes recording Mute Swan 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 →
Clearfield420161990
Drehersville 2320232023
Slippery Rk219821982
Doe Run220082006
Wild Creek220012001
Mt Gretna 2220062006
Wakena220232003
Harmonsburg120162016
Greentown119901983
Elizabethvil120082003
New Ringgold120152015
Schaefferstown 2120172002

Mute Swan Population Trend in Other States

californiaconnecticutdelawareillinoisindianakentuckymarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorkohiorhode-islandvirginiawisconsin

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