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

Rose-breasted Grosbeak Population Trend in Massachusetts

All statesForest birds

Rose-breasted Grosbeak in Massachusetts has declined: down 29% on the route-weighted index since 1969.

-29%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 →
29Routes 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 Rose-breasted Grosbeak 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 Rose-breasted Grosbeak in Massachusetts. See the full index history below.

Rose-breasted Grosbeak Population Forecast in Massachusetts

If the recent trend holds, Rose-breasted Grosbeak in Massachusetts is projected to fall about 34% by 2030 — from 2.2 in 2025 to a central estimate of 1.4 (95% range 0.00–3.1). A 5-year backtest shows a typical error of ±16.9%, with 100% of held-out values landing inside the 95% band.

-34%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 →
1.4Projected 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 →
0.00–3.195% 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 →
±16.9%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, Rose-breasted Grosbeak in Massachusetts is projected to fall about 34% by 2030 — from 2.2 in 2025 to a central estimate of 1.4 (95% range 0.00–3.1). A 5-year backtest shows a typical error of ±16.9%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20261.60.003.3
20271.50.003.2
20281.50.003.2
20291.50.003.2
20301.40.003.1

Rose-breasted Grosbeak Survey Routes in Massachusetts

Routes recording Rose-breasted Grosbeak 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 →
N Oxford720251968
Maynard620251967
Sheffield620221969
S Barre520251968
Warren 2520252010
Belchertown420251967
Warren320091968
Pittsfield320161967
Hancock320151997
Chilmark219831971
Ware River220221993
Princeton219761969
Chesterfield220251967
Cheshire219941969
Monterey220252019
E Dennis120102010
Marion120011980
Prattville120171973
Brockton120181973
Newburyport120221967
Littleton120251967
Mansfield120181969
E Pepperell119931967
N Orange120251968
Cummington120141968

Rose-breasted Grosbeak Population Trend in Other States

arkansasconnecticutgeorgiaillinoisindianaiowakansaskentuckymainemarylandmichiganminnesotamissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseevermontvirginiawest-virginiawisconsinwyoming

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