BirdAnalyst
Species · BCR 13 · BBS 2025 Release · 1966–2024

Swamp Sparrow In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainGeneralists

Swamp Sparrow in Lower Great Lakes / St. Lawrence Plain has surged: up 94% on the route-weighted index since 1968.

+94%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 →
80Routes In RegionSurvey 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 SignalsNotable 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 →

Swamp Sparrow has surged in Lower Great Lakes / St. Lawrence Plain: up 94% on the route-weighted index since 1968.

Swamp Sparrow In Lower Great Lakes / St. Lawrence Plain Population Forecast

If the recent trend holds, Swamp Sparrow in Lower Great Lakes / St. Lawrence Plain is projected to fall about 27% by 2029 — from 2.3 in 2024 to a central estimate of 1.7 (95% range 0.96–2.4). A 5-year backtest shows a typical error of ±23.6%, with 40% of held-out values landing inside the 95% band.

-27%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 →
1.7Projected 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 →
0.96–2.495% 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 →
±23.6%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, Swamp Sparrow in Lower Great Lakes / St. Lawrence Plain is projected to fall about 27% by 2029 — from 2.3 in 2024 to a central estimate of 1.7 (95% range 0.96–2.4). A 5-year backtest shows a typical error of ±23.6%, with 40% 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 →
20251.60.912.3
20261.60.932.3
20271.60.942.3
20281.70.952.4
20291.70.962.4

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Swamp Sparrow in Lower Great Lakes / St. Lawrence Plain.
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 →
HinesburgVERMONT141994
Ferris CrnrsPENNSYLVANIA132024
NaplesNEW-YORK102024
North EastonNEW-YORK92024
ParishvilleNEW-YORK82024
PhiladelphiaNEW-YORK82024
NashvilleNEW-YORK72018
ByronNEW-YORK62024
ChurchvilleNEW-YORK62024
CrescentNEW-YORK62024
Oriskany FlsNEW-YORK52024
RandolphNEW-YORK52018
Cicero CtrNEW-YORK52024
N WilmurtNEW-YORK51998
BalmatNEW-YORK52008
GarrettsvileOHIO51991
TrumansburgNEW-YORK42024
WatertownNEW-YORK42012
OgdensburgNEW-YORK42024
Sugar GrovePENNSYLVANIA42024
RhinebeckNEW-YORK32018
Ballston LkNEW-YORK31970
CastileNEW-YORK32024
SheridanNEW-YORK32024
OneidaNEW-YORK32010

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