BirdAnalyst
Species · New York · BBS 2026 Release · 1966–2025

Chestnut-sided Warbler Population Trend in New York

All statesForest birds

Chestnut-sided Warbler in New York has surged: up 95% on the route-weighted index since 1968.

+95%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 →
123Routes 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 →
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 Chestnut-sided Warbler 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 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 →

Chestnut-sided Warbler has surged in New York: up 95% on the route-weighted index since 1968.

Chestnut-sided Warbler Population Forecast in New York

If the recent trend holds, Chestnut-sided Warbler in New York is projected to fall about 22% by 2030 — from 8.5 in 2025 to a central estimate of 6.6 (95% range 4.6–8.6). A 5-year backtest shows a typical error of ±20%, with 40% of held-out values landing inside the 95% band.

-22%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 →
6.6Projected 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 →
4.6–8.695% 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 →
±20%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, Chestnut-sided Warbler in New York is projected to fall about 22% by 2030 — from 8.5 in 2025 to a central estimate of 6.6 (95% range 4.6–8.6). A 5-year backtest shows a typical error of ±20%, 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 →
20266.54.58.5
20276.54.58.5
20286.54.58.5
20296.54.58.6
20306.64.68.6

Chestnut-sided Warbler Survey Routes in New York

Routes recording Chestnut-sided Warbler 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 →
Degrasse4120251980
Wanakena3420251980
Oneonta2620251968
Cattaraugus2620191971
Platte Cove2420181968
Parishville2420251971
S Berne 22420252014
Mcdonough2320171967
Kasoag2220251966
Highmarket2020251969
Dexter Lake2019751968
Alder Creek1920041969
Meridale1820251967
S Berne1720131967
N Wilmurt1719981967
St Regis Fls1720171976
Dryden1520251968
Balmat1520081977
Downsville1520191982
Milford1520231978
Oxford 21520241977
Sabattis1419831966
Medusa1320241970
Mt Morris1320251967
North River1320251966

Chestnut-sided Warbler Population Trend in Other States

alabamaarkansascoloradoconnecticutgeorgiaillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotanevadanew-hampshirenew-jerseynorth-carolinanorth-dakotaohiopennsylvaniarhode-islandtennesseevermontvirginiawest-virginiawisconsinwyoming

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