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Species · Massachusetts · BBS 2026 Release · 1966–2025

Gray Catbird Population Trend in Massachusetts

All statesForest birds

Gray Catbird in Massachusetts has risen sharply: up 70% on the route-weighted index since 1968.

+70%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 Gray Catbird 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 →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Gray Catbird has risen sharply in Massachusetts: up 70% on the route-weighted index since 1968.

Gray Catbird Population Forecast in Massachusetts

If the recent trend holds, Gray Catbird in Massachusetts is projected to fall about 19% by 2030 — from 39 in 2025 to a central estimate of 31 (95% range 24–39). A 5-year backtest shows a typical error of ±21.6%, with 40% of held-out values landing inside the 95% band.

-19%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 →
31Projected 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 →
24–3995% 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 →
±21.6%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, Gray Catbird in Massachusetts is projected to fall about 19% by 2030 — from 39 in 2025 to a central estimate of 31 (95% range 24–39). A 5-year backtest shows a typical error of ±21.6%, with 40% 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 →
2026302338
2027312338
2028312438
2029312438
2030312439

Gray Catbird Survey Routes in Massachusetts

Routes recording Gray Catbird 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 →
Marion8420251966
Brockton7520191967
Wellfleet 27220252016
Gay Head7020251996
Belchertown5820251967
Newburyport5720221967
Warren 25020252010
Chilmark4619831969
Mansfield3920251968
Maynard3620251967
Monterey3620252019
Holden3520251977
Pittsfield3420161967
E Dennis3320211967
N Oxford3320251968
S Barre3220251968
Prattville3120191966
Cheshire3019941969
Wellfleet2920071966
Warren2520091968
E Pepperell2219941966
Littleton1820251967
N Orange1620251968
Ware River1520221993
N. Andover1520251995

Gray Catbird Population Trend in Other States

alabamaarizonaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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