BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Lark Sparrow In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionGrassland birds

Lark Sparrow in Prairie Hardwood Transition has surged: up 91% on the route-weighted index since 1972.

+91%Since 1972TrendPercent 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 →
22Routes 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 →
41YearsYears 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 →

Lark Sparrow has surged in Prairie Hardwood Transition: up 91% on the route-weighted index since 1972.

Lark Sparrow In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Lark Sparrow in Prairie Hardwood Transition is projected to fall about 21% by 2029 — from 0.10 in 2024 to a central estimate of 0.08 (95% range 0.02–0.13). A 5-year backtest shows a typical error of ±76.8%, with 100% of held-out values landing inside the 95% band.

-21%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 →
0.08Projected 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 →
0.02–0.1395% 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 →
±76.8%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, Lark Sparrow in Prairie Hardwood Transition is projected to fall about 21% by 2029 — from 0.10 in 2024 to a central estimate of 0.08 (95% range 0.02–0.13). A 5-year backtest shows a typical error of ±76.8%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.070.020.13
20260.070.020.13
20270.070.020.13
20280.070.020.13
20290.080.020.13

Routes In Prairie Hardwood Transition

Routes recording Lark Sparrow in Prairie Hardwood Transition.
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 →
MerideanWISCONSIN32024
KnoxINDIANA22023
New LondonMINNESOTA22000
LimestoneOHIO22015
HatfieldWISCONSIN21979
N FreedomWISCONSIN22024
PrincetonWISCONSIN22014
Fall RiverWISCONSIN22024
Prairie Du ChienWISCONSIN22014
BriggsvilleWISCONSIN22024
BeloitWISCONSIN22009
Money CreekMINNESOTA12018
MillvilleMINNESOTA12007
PrincetonMINNESOTA12021
EdwardsMINNESOTA12017
GlenwoodMINNESOTA11994
Sherburne NrMINNESOTA12024
CumberlandWISCONSIN12013
TrempealeauWISCONSIN12018
CadottWISCONSIN12011
Oconto FallsWISCONSIN11990
Buena VistaWISCONSIN12022

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