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

Forest Birds In Massachusetts

All statesMassachusetts

47 species in this guild. As a group they are +29%Guild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology → since 1968.

Guild SignalsNotable 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 forest birds in Massachusetts. See the full index history below.

Forecast

If the recent trend holds, Forest birds in Massachusetts is projected to fall about 11% by 2029 — from 7.3 in 2024 to a central estimate of 6.5 (95% range 5.4–7.5). A 5-year backtest shows a typical error of ±16.8%, with 20% of held-out values landing inside the 95% band.

-11%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 →
6.5Projected 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 →
5.4–7.595% 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 →
±16.8%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, Forest birds in Massachusetts is projected to fall about 11% by 2029 — from 7.3 in 2024 to a central estimate of 6.5 (95% range 5.4–7.5). A 5-year backtest shows a typical error of ±16.8%, with 20% 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 →
20256.45.37.4
20266.45.37.5
20276.45.37.5
20286.45.47.5
20296.55.47.5

Member Species In Massachusetts

Forest birds species in Massachusetts.
TrendPercent 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 →
Canada WarblerParulidae-72%
Nashville WarblerParulidae-71%
Prairie WarblerParulidae-70%
Wood ThrushTurdidae-66%
Golden-winged WarblerParulidae-58%
Swainson's ThrushTurdidae-49%
Magnolia WarblerParulidae-49%
American RobinTurdidae-19%
Mourning WarblerParulidae-18%
Common YellowthroatParulidae-12%
Blue-winged WarblerParulidae-10%
Black-and-white WarblerParulidae+20%
Black-throated Green WarblerParulidae+32%
Hermit ThrushTurdidae+33%
Black-throated Blue WarblerParulidae+49%
Black-capped ChickadeeParidae+50%
Chestnut-sided WarblerParulidae+50%
VeeryTurdidae+51%
Northern House WrenTroglodytidae+66%
Hairy WoodpeckerPicidae+74%
Worm-eating WarblerParulidae+93%
Yellow WarblerParulidae+108%
American RedstartParulidae+195%
OvenbirdParulidae+204%
Blackburnian WarblerParulidae+208%
Downy WoodpeckerPicidae+249%
Red-eyed VireoVireonidae+251%
Northern WaterthrushParulidae+256%
Golden-crowned KingletRegulidae+266%
Winter WrenTroglodytidae+283%
Marsh WrenTroglodytidae+350%
White-breasted NuthatchSittidae+351%
Red-breasted NuthatchSittidae+364%
Northern ParulaParulidae+444%
Brown CreeperCerthiidae+462%
Pine WarblerParulidae+499%
Eastern BluebirdTurdidae+502%
Louisiana WaterthrushParulidae+541%
Yellow-bellied SapsuckerPicidae+566%
Warbling VireoVireonidae+589%
Yellow-throated VireoVireonidae+810%
Blue-headed VireoVireonidae+994%
Pileated WoodpeckerPicidae14×
Blue-gray GnatcatcherPolioptilidae14×
Red-bellied WoodpeckerPicidae22×
Carolina WrenTroglodytidae67×
Tufted TitmouseParidae113×

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