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

Chestnut-sided Warbler Population Trend in Virginia

All statesForest birds

Chestnut-sided Warbler in Virginia has surged: up 402% on the route-weighted index since 1969.

+402%Since 1969TrendPercent 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 →
27Routes 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 →
57YearsYears 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 VirginiaNotable 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 Virginia: up 402% on the route-weighted index since 1969.

Chestnut-sided Warbler Population Forecast in Virginia

If the recent trend holds, Chestnut-sided Warbler in Virginia is projected to rise about 384% by 2029 — from 0.15 in 2024 to a central estimate of 0.74 (95% range 0.26–1.2). A 5-year backtest shows a typical error of ±237.6%, with 20% of held-out values landing inside the 95% band.

+384%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 →
0.74Projected 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 →
0.26–1.295% 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 →
±237.6%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 Virginia is projected to rise about 384% by 2029 — from 0.15 in 2024 to a central estimate of 0.74 (95% range 0.26–1.2). A 5-year backtest shows a typical error of ±237.6%, with 20% of held-out values landing inside the 95% band.19672029
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 →
20250.700.221.2
20260.710.231.2
20270.720.241.2
20280.730.251.2
20290.740.261.2

Chestnut-sided Warbler Survey Routes in Virginia

Routes recording Chestnut-sided Warbler in Virginia.
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 →
Iron Mountain 21620132012
Iron Mountain 3620232014
Tryme520001996
Big Meadows520241993
Mountain Lk.420181992
Rural Retrt320161982
Loft Mtn320191993
Stanley219691969
New Market220192005
Nat Tunnel219961996
Potts Mtn.220131993
Elamsville219791979
W Augusta120231968
Bald Knob120241992
Edinburg119931993
Douthat120051992
Isom119811979
Putnam120111971
Covington120221967
Shenandoa Np120241993
Iron Mtn.120111992
Front Royal120181993
Pine Mtn.120091999
Saltville120131970
Irisburg120042003

Chestnut-sided Warbler Population Trend in Other States

alabamaarkansascoloradoconnecticutgeorgiaillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotanevadanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandtennesseevermontwest-virginiawisconsinwyoming

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