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

Scarlet Tanager Population Trend in Massachusetts

All statesForest birds

Scarlet Tanager in Massachusetts has edged up: up 12% on the route-weighted index since 1968.

+12%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 →
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 Scarlet Tanager 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 Scarlet Tanager in Massachusetts. See the full index history below.

Scarlet Tanager Population Forecast in Massachusetts

If the recent trend holds, Scarlet Tanager in Massachusetts is projected to fall about 14% by 2030 — from 4.3 in 2025 to a central estimate of 3.6 (95% range 1.5–5.8). A 5-year backtest shows a typical error of ±15.6%, with 100% of held-out values landing inside the 95% band.

-14%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 →
3.6Projected 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 →
1.5–5.895% 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 →
±15.6%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, Scarlet Tanager in Massachusetts is projected to fall about 14% by 2030 — from 4.3 in 2025 to a central estimate of 3.6 (95% range 1.5–5.8). A 5-year backtest shows a typical error of ±15.6%, with 100% 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 →
20263.81.65.9
20273.71.65.9
20283.71.55.9
20293.71.55.8
20303.61.55.8

Scarlet Tanager Survey Routes in Massachusetts

Routes recording Scarlet Tanager 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 →
Monterey2020252019
N Orange1220251968
Cummington 21120252015
Ware River1020221993
Pittsfield820161967
Sheffield820221969
Brockton620171967
Maynard520251967
Princeton519761969
Cummington520141968
N Oxford420251968
Chesterfield420251967
Cheshire419941969
Warren 2420252010
Hancock420151997
Prattville320191966
Littleton320231967
S Barre320251968
Newburyport220221967
E Pepperell219941968
Belchertown220251967
Warren220091968
Wellfleet 2220172017
Holden220251977
N. Andover220241995

Scarlet Tanager Population Trend in Other States

alabamaarkansasconnecticutdelawaregeorgiaillinoisindianaiowakansaskentuckymainemarylandmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseevermontvirginiawest-virginiawisconsin

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