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Species · BCR 4 · BBS 2026 Release · 1966–2025

Lincoln's Sparrow In BCR 4

All regionsBCR 4Forest birds

Lincoln's Sparrow in BCR 4 has surged: up 87% on the route-weighted index since 1982.

+87%Since 1982TrendPercent 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 →
65Routes 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 →
44YearsYears 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 →

Lincoln's Sparrow has surged in BCR 4: up 87% on the route-weighted index since 1982.

Lincoln's Sparrow In BCR 4 Population Forecast

If the recent trend holds, Lincoln's Sparrow in BCR 4 is projected to rise about 34% by 2030 — from 7.4 in 2025 to a central estimate of 9.9 (95% range 6.5–13). A 5-year backtest shows a typical error of ±15.2%, with 100% of held-out values landing inside the 95% band.

+34%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 →
9.9Projected 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 →
6.5–1395% 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 →
±15.2%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, Lincoln's Sparrow in BCR 4 is projected to rise about 34% by 2030 — from 7.4 in 2025 to a central estimate of 9.9 (95% range 6.5–13). A 5-year backtest shows a typical error of ±15.2%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20269.45.913
20279.56.113
20289.76.213
20299.86.413
20309.96.513

Routes In BCR 4

Routes recording Lincoln's Sparrow in BCR 4.
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 →
Hather CreekALASKA292024
Burma RoadALASKA232025
Kanuti LakeALASKA232024
SourdoughALASKA212025
Tower BluffsALASKA182025
DeltaALASKA172024
CohoeALASKA162023
CircleALASKA152025
PetersvilleALASKA152025
EagleALASKA142025
KalifonskyALASKA142025
Caribou Mtn.ALASKA142024
Goose BayALASKA131982
Kanuti CanynALASKA132024
WillowALASKA122025
ChickenALASKA122025
Mud RiverALASKA122024
LivengoodALASKA102021
ChistochinaALASKA102025
Mt. FairplayALASKA102025
ToklatALASKA92024
SavageALASKA92025
Tangle LakesALASKA91987
RubyALASKA92025
Paxson LakeALASKA91997

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