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

Scarlet Tanager Population Trend in Massachusetts

All statesGeneralists

Scarlet Tanager in Massachusetts has held roughly steady: up 8% on the route-weighted index since 1968.

+8%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 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 rise about 21% by 2029 — from 3.0 in 2024 to a central estimate of 3.6 (95% range 1.4–5.8). A 5-year backtest shows a typical error of ±16.1%, 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 →
3.6Projected 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 →
1.4–5.895% 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 →
±16.1%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, Scarlet Tanager in Massachusetts is projected to rise about 21% by 2029 — from 3.0 in 2024 to a central estimate of 3.6 (95% range 1.4–5.8). A 5-year backtest shows a typical error of ±16.1%, 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 →
20253.81.65.9
20263.71.55.9
20273.71.55.9
20283.71.55.9
20293.61.45.8

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 →
Monterey1220242019
Ware River1020221993
N Orange820241968
Pittsfield820161967
Sheffield820221969
Brockton620171967
Princeton519761969
Belchertown520241967
Cummington520141968
Cummington 2520242015
Cheshire419941969
Hancock420151997
Prattville320191966
Maynard320221967
Littleton320231967
S Barre320241968
Newburyport220221967
N Oxford220241968
E Pepperell219941968
Warren220091968
Chesterfield220241967
Wellfleet 2220172017
Holden220241977
N. Andover220241995
Warren 2220242010

Scarlet Tanager Population Trend in Other States

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

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