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

Rose-breasted Grosbeak Population Trend in Massachusetts

All statesGeneralists

Rose-breasted Grosbeak in Massachusetts has declined: down 28% on the route-weighted index since 1969.

-28%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 →
57YearsYears 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 14% by 2029 — from 1.7 in 2024 to a central estimate of 1.4 (95% range 0.00–3.1). A 5-year backtest shows a typical error of ±17.3%, with 100% of held-out values landing inside the 95% band.

-14%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 →
1.4Projected 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 →
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 →
±17.3%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 14% by 2029 — from 1.7 in 2024 to a central estimate of 1.4 (95% range 0.00–3.1). A 5-year backtest shows a typical error of ±17.3%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20251.60.003.3
20261.50.003.2
20271.50.003.2
20281.50.003.2
20291.40.003.1

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 →
Belchertown620241967
Sheffield620221969
S Barre520241968
Cummington 2420242015
Warren320091968
Pittsfield320161967
Hancock320151997
Chilmark219831971
Ware River220221993
Maynard220211967
N Oxford220241968
Princeton219761969
Chesterfield220241967
Cheshire219941969
Monterey220242019
N. Andover220241995
Warren 2220232010
E Dennis120102010
Marion120011980
Prattville120171973
Brockton120181973
Newburyport120221967
Littleton120241967
Mansfield120181969
E Pepperell119931967

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 2026-05-22.