BirdAnalyst
Species · BCR 13 · BBS 2026 Release · 1966–2025

Field Sparrow In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainForest birds

Field Sparrow in Lower Great Lakes / St. Lawrence Plain has fallen sharply: down 56% on the route-weighted index since 1968.

-56%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 →
84Routes 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 →
59YearsYears 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 declinecomputed 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 →

Field Sparrow has fallen sharply in Lower Great Lakes / St. Lawrence Plain: down 56% on the route-weighted index since 1968.

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

If the recent trend holds, Field Sparrow in Lower Great Lakes / St. Lawrence Plain is projected to fall about 72% by 2030 — from 5.0 in 2025 to a central estimate of 1.4 (95% range 0.00–4.1). A 5-year backtest shows a typical error of ±69.8%, with 40% of held-out values landing inside the 95% band.

-72%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 →
1.4Projected 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 →
0.00–4.195% 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 →
±69.8%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, Field Sparrow in Lower Great Lakes / St. Lawrence Plain is projected to fall about 72% by 2030 — from 5.0 in 2025 to a central estimate of 1.4 (95% range 0.00–4.1). A 5-year backtest shows a typical error of ±69.8%, with 40% 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 →
20261.90.004.6
20271.80.004.5
20281.70.004.4
20291.50.004.2
20301.40.004.1

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Field 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 →
ChurchvilleNEW-YORK262025
MacdougallNEW-YORK212025
West SenecaNEW-YORK202004
HebronOHIO182025
NaplesNEW-YORK172025
LucerneOHIO162025
RhinebeckNEW-YORK142025
N VictoryNEW-YORK121972
WaylandOHIO122017
BranchportNEW-YORK112024
CayugaNEW-YORK102025
Mt MorrisNEW-YORK102025
Valley CityOHIO92025
OrleansNEW-YORK82025
CastileNEW-YORK82025
ArgyleNEW-YORK82024
GarrettsvileOHIO81991
SheridanNEW-YORK62025
Harris HillNEW-YORK62025
New SomersetOHIO61993
AkeleyPENNSYLVANIA61979
North PownalVERMONT62025
GhentNEW-YORK52025
ByronNEW-YORK52025
N Victory 2NEW-YORK52021

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