BirdAnalyst
Species · New York · BBS 2025 Release · 1966–2024

Henslow's Sparrow Population Trend in New York

All statesGrassland birds

Henslow's Sparrow in New York has collapsed: down 82% on the route-weighted index since 1968.

-82%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 →
42Routes 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 →
36YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Henslow's Sparrow Trends in New YorkNotable 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 →

Henslow's Sparrow has collapsed in New York: down 82% on the route-weighted index since 1968.

Henslow's Sparrow Population Forecast in New York

If the recent trend holds, Henslow's Sparrow in New York is projected to stay roughly flat through 2011, near 0.00 (95% range 0.00–0.15). A 5-year backtest shows a typical error of ±544.3%, with 40% of held-out values landing inside the 95% band.

n/aChange by 2011TrendPercent 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 →
0.00Projected 2011 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1595% 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 →
±544.3%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, Henslow's Sparrow in New York is projected to stay roughly flat through 2011, near 0.00 (95% range 0.00–0.15). A 5-year backtest shows a typical error of ±544.3%, with 40% of held-out values landing inside the 95% band.19662011
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 →
20070.000.000.15
20080.000.000.15
20090.000.000.15
20100.000.000.15
20110.000.000.15

Henslow's Sparrow Survey Routes in New York

Routes recording Henslow's Sparrow in New York.
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 →
Lisle720031967
Watertown519731969
Oneida419761968
Number Four319691969
Medusa219691969
Trumansburg219941966
Phillips Cr220061968
Swain219831968
Branchport219971967
Sheridan219891966
Pulaski219911968
Somers119751975
Durham119691969
Laurens119811981
Whitney Pt119721966
Coventryvile119781969
Corbettsvile119861969
Oriskany Fls119771977
E Newark119931992
Romulus119931968
Dryden119931966
Macdougall119891972
Vestal Ctr119991966
Orleans119971979
Rushville119701970

Henslow's Sparrow Population Trend in Other States

delawareillinoisindianaiowakansaskentuckymarylandmichiganminnesotamissourinebraskanorth-carolinanorth-dakotaohiooklahomapennsylvaniasouth-dakotavermontvirginiawest-virginiawisconsin

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