BirdAnalyst
Species · Virginia · BBS 2026 Release · 1966–2025

Northern Parula Population Trend in Virginia

All statesForest birds

Northern Parula in Virginia has surged: up 201% on the route-weighted index since 1968.

+201%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 →
79Routes 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 Northern Parula 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 →

Northern Parula has surged in Virginia: up 201% on the route-weighted index since 1968.

Northern Parula Population Forecast in Virginia

If the recent trend holds, Northern Parula in Virginia is projected to fall about 31% by 2030 — from 3.5 in 2025 to a central estimate of 2.4 (95% range 1.5–3.4). A 5-year backtest shows a typical error of ±37.2%, with 20% of held-out values landing inside the 95% band.

-31%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 →
2.4Projected 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 →
1.5–3.495% 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 →
±37.2%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, Northern Parula in Virginia is projected to fall about 31% by 2030 — from 3.5 in 2025 to a central estimate of 2.4 (95% range 1.5–3.4). A 5-year backtest shows a typical error of ±37.2%, with 20% 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 →
20262.41.43.3
20272.41.53.3
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20302.41.53.4

Northern Parula Survey Routes in Virginia

Routes recording Northern Parula 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 →
Isom2120241969
Truhart2120241996
White Stone1720251966
Pine Mtn.1720251996
Brandon1420251992
Newsoms1220241968
Rural Retrt1220251982
Port Royal1020251977
Putnam1020251969
Nat Tunnel1020251981
Irisburg820251988
Dryden820251994
Glenwood720231992
Walkers720231992
Covesville620251968
Newville620241991
Mannboro520251968
Church Road520251966
Sharps520251967
Brodnax520251973
Hebron 2520252023
Pw Forest Pk520091992
Saltville420251969
Moran420251996
Appomattox420241996

Northern Parula Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontwest-virginiawisconsin

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