BirdAnalyst
Species · New Hampshire · BBS 2025 Release · 1966–2024

Wood Thrush Population Trend in New Hampshire

All statesForest birds

Wood Thrush in New Hampshire has collapsed: down 88% on the route-weighted index since 1968.

-88%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 →
26Routes 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 Wood Thrush Trends in New HampshireNotable 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 declinecomputed 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 →

Wood Thrush has collapsed in New Hampshire: down 88% on the route-weighted index since 1968.

Wood Thrush Population Forecast in New Hampshire

If the recent trend holds, Wood Thrush in New Hampshire is projected to fall about 100% by 2029 — from 2.5 in 2024 to a central estimate of 0.00 (95% range 0.00–6.5). A 5-year backtest shows a typical error of ±185.5%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–6.595% 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 →
±185.5%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, Wood Thrush in New Hampshire is projected to fall about 100% by 2029 — from 2.5 in 2024 to a central estimate of 0.00 (95% range 0.00–6.5). A 5-year backtest shows a typical error of ±185.5%, with 100% 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 →
20250.000.006.5
20260.000.006.5
20270.000.006.5
20280.000.006.5
20290.000.006.5

Wood Thrush Survey Routes in New Hampshire

Routes recording Wood Thrush in New Hampshire.
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 →
Crawford Not2019751966
Brentwood1619981966
Wilmot720241966
Hopkinton620241966
East Kingston620241999
Dover520241966
Gilmantn I W520241969
Strafford420241966
Peterborough320241966
Fitzwilliam320241966
Concord320241966
Canterbury320241966
Milan320241966
Epsom220231966
Walpole220241966
Marlow220241966
Jefferson Hl220231966
Clarksville220071967
Dixville Notch 2220242019
Mt Chocorua120221966
Lempster120231966
Franconia120241966
Stratford120211966
Dixvil Notch120151966
Glen120241975

Wood Thrush Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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