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Species · Massachusetts · BBS 2025 Release · 1966–2024

Black-and-white Warbler Population Trend in Massachusetts

All statesForest birds

Black-and-white Warbler in Massachusetts has edged up: up 20% on the route-weighted index since 1968.

+20%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 →
32Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-and-white Warbler Trends in MassachusettsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Black-and-white Warbler in Massachusetts. See the full index history below.

Black-and-white Warbler Population Forecast in Massachusetts

If the recent trend holds, Black-and-white Warbler in Massachusetts is projected to fall about 21% by 2029 — from 4.1 in 2024 to a central estimate of 3.3 (95% range 2.0–4.6). A 5-year backtest shows a typical error of ±11.1%, 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 →
3.3Projected 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 →
2.0–4.695% 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 →
±11.1%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, Black-and-white Warbler in Massachusetts is projected to fall about 21% by 2029 — from 4.1 in 2024 to a central estimate of 3.3 (95% range 2.0–4.6). A 5-year backtest shows a typical error of ±11.1%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20253.32.04.6
20263.32.04.6
20273.32.04.6
20283.32.04.6
20293.32.04.6

Black-and-white Warbler Survey Routes in Massachusetts

Routes recording Black-and-white Warbler in Massachusetts.
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 →
Chesterfield2820241967
N Orange1320241968
Pittsfield920161967
Cheshire819941969
Cummington720141968
Monterey720242019
Ware River620221993
Hancock620151997
Belchertown520241967
S Barre520241968
Prattville320191966
Princeton319761969
Cape Cod Ns319961989
Chilmark219831969
Marion220231969
Wellfleet220071966
Warren220081968
Sheffield220221971
Holden220221977
N. Andover220051995
Warren 2220242010
Cummington 2220242015
E Dennis120161967
Brockton120071967
Newburyport120151967

Black-and-white Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawaregeorgiaillinoisindianakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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