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

Northern Mockingbird Population Trend in Massachusetts

All statesGeneralists

Northern Mockingbird in Massachusetts has surged: up 211% on the route-weighted index since 1968.

+211%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 →
30Routes 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 Northern Mockingbird 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 →

Northern Mockingbird has surged in Massachusetts: up 211% on the route-weighted index since 1968.

Northern Mockingbird Population Forecast in Massachusetts

If the recent trend holds, Northern Mockingbird in Massachusetts is projected to rise about 80% by 2030 — from 0.94 in 2025 to a central estimate of 1.7 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±130.7%, with 100% of held-out values landing inside the 95% band.

+80%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 →
1.7Projected 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 →
0.00–7.095% 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 →
±130.7%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, Northern Mockingbird in Massachusetts is projected to rise about 80% by 2030 — from 0.94 in 2025 to a central estimate of 1.7 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±130.7%, 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 →
20261.90.007.2
20271.90.007.1
20281.80.007.1
20291.70.007.0
20301.70.007.0

Northern Mockingbird Survey Routes in Massachusetts

Routes recording Northern Mockingbird 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 →
E Pepperell1519941971
Pittsfield619921979
Newburyport520221970
Maynard520251971
Mansfield520251972
Cheshire519941971
Warren420091968
Chilmark319831971
N Oxford320241974
Cape Cod Ns319991989
Gay Head320251996
Prattville220191974
Littleton220241974
Princeton219751971
Belchertown220241973
Chesterfield220061978
Ware River219931993
N. Andover220191995
Warren 2220252010
E Dennis120191969
Marion120221970
Wellfleet120051966
Brockton120191967
S Barre120211976
N Orange120001986

Northern Mockingbird Population Trend in Other States

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

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