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

Lark Sparrow Population Trend in Washington

All statesGrassland birds

Lark Sparrow in Washington has surged: up 939% on the route-weighted index since 1970.

+939%Since 1970TrendPercent 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 →
44Routes 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 →
55YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Lark Sparrow Trends in WashingtonNotable 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 →

Lark Sparrow has surged in Washington: up 939% on the route-weighted index since 1970.

Lark Sparrow Population Forecast in Washington

If the recent trend holds, Lark Sparrow in Washington is projected to rise about 14% by 2029 — from 0.82 in 2024 to a central estimate of 0.94 (95% range 0.38–1.5). A 5-year backtest shows a typical error of ±19.7%, with 100% of held-out values landing inside the 95% band.

+14%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 →
0.94Projected 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 →
0.38–1.595% 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 →
±19.7%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, Lark Sparrow in Washington is projected to rise about 14% by 2029 — from 0.82 in 2024 to a central estimate of 0.94 (95% range 0.38–1.5). A 5-year backtest shows a typical error of ±19.7%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.890.331.5
20260.910.341.5
20270.920.361.5
20280.930.371.5
20290.940.381.5

Lark Sparrow Survey Routes in Washington

Routes recording Lark Sparrow in Washington.
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 →
Horn Rapids1720242005
Richland1320242006
Scootney Reservoir920242009
Moses Coulee920231993
Snowden819941981
Arid Land Er619961988
Mesa620081994
Brewster420151977
Moses Lake420221973
Hatton419941992
Hanford Site319961988
Selah320002000
Harrington320121980
Columbia Nwr320221992
Wilbur320161993
Turnbull Nwr220211996
Wapato220222019
Mercer220221989
Ellensburg220241999
Othello219891985
Nighthawk220241993
Keystone220141994
Harwood219971994
Potholes220101997
Pomeroy220222014

Lark Sparrow Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoidahoillinoisindianaiowakansaskentuckylouisianaminnesotamississippimissourimontananebraskanevadanew-mexiconorth-dakotaohiooklahomaoregonsouth-dakotatennesseetexasutahwisconsinwyoming

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