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

Least Flycatcher Population Trend in Vermont

All statesAerial insectivores

Least Flycatcher in Vermont has fallen sharply: down 50% on the route-weighted index since 1968.

-50%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 →
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 Least Flycatcher Trends in VermontNotable 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 →

Least Flycatcher has fallen sharply in Vermont: down 50% on the route-weighted index since 1968.

Least Flycatcher Population Forecast in Vermont

If the recent trend holds, Least Flycatcher in Vermont is projected to stay roughly flat through 2030, near 3.4 (95% range 0.02–6.9). A 5-year backtest shows a typical error of ±14.6%, with 100% of held-out values landing inside the 95% band.

-6%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 →
3.4Projected 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 →
0.02–6.995% 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 →
±14.6%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, Least Flycatcher in Vermont is projected to stay roughly flat through 2030, near 3.4 (95% range 0.02–6.9). A 5-year backtest shows a typical error of ±14.6%, 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 →
20263.70.247.1
20273.60.197.0
20283.60.137.0
20293.50.086.9
20303.40.026.9

Least Flycatcher Survey Routes in Vermont

Routes recording Least Flycatcher in Vermont.
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 →
Waterville1819801969
Shaftsbury1520251966
Fletcher1120251973
Marlboro820251966
Hardwick720241969
S Wallingfrd620221966
Hinesburg619941971
W Rutland520251966
Gaysville420251966
St Johnsbury420251970
Middlesex420251968
East Calais420241966
Newbury420041986
Greensboro420251967
Stowe420241988
Northfld Fls320251980
North Pownal220251967
Landgrove220251966
Post Mills220221966
Newbury 2220222005
Bristol220251995
Stratton120251966
S Reading120241966
East Haven120251966
Colchester120171986

Least Flycatcher Population Trend in Other States

alaskaarkansascaliforniacoloradoconnecticutgeorgiaidahoillinoisindianaiowakentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseeutahvirginiawashingtonwest-virginiawisconsinwyoming

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