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

Bobolink Population Trend in New Hampshire

All statesGrassland birds

Bobolink in New Hampshire has fallen sharply: down 63% on the route-weighted index since 1968.

-63%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 →
25Routes 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 Bobolink 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 →

Bobolink has fallen sharply in New Hampshire: down 62% on the route-weighted index since 1968.

Bobolink Population Forecast in New Hampshire

If the recent trend holds, Bobolink in New Hampshire is projected to stay roughly flat through 2029, near 2.1 (95% range 0.00–4.7). A 5-year backtest shows a typical error of ±14.8%, with 100% of held-out values landing inside the 95% band.

-10%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 →
2.1Projected 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 →
0.00–4.795% 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 →
±14.8%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, Bobolink in New Hampshire is projected to stay roughly flat through 2029, near 2.1 (95% range 0.00–4.7). A 5-year backtest shows a typical error of ±14.8%, 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 →
20252.60.005.3
20262.50.005.2
20272.40.005.0
20282.20.004.9
20292.10.004.7

Bobolink Survey Routes in New Hampshire

Routes recording Bobolink 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 →
Canterbury2020241966
Dixville Notch 21620242018
Dixvil Notch1420171966
Dover1120231966
Brentwood419981966
Marlow420241966
Fitzwilliam320231966
Epsom320161966
Jefferson Hl320221966
Glen320231975
Concord220221966
Wilmot220241966
Lempster220241966
Franconia220221966
Milan220241966
Clarksville220241966
Peterborough120131966
Hopkinton120231966
Strafford120161966
Gilmantn I W120241969
Mt Chocorua120241969
Walpole120241967
Crawford Not119721972
Stratford120211966
East Kingston120231999

Bobolink Population Trend in Other States

californiacoloradoconnecticutidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotautahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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