BirdAnalyst
Species · Vermont · BBS 2025 Release · 1966–2024

Least Flycatcher Population Trend in Vermont

All statesAerial insectivores

Least Flycatcher in Vermont has declined: down 46% on the route-weighted index since 1968.

-46%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 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 →

No notable trend signals for Least Flycatcher in Vermont. See the full index history below.

Least Flycatcher Population Forecast in Vermont

If the recent trend holds, Least Flycatcher in Vermont is projected to stay roughly flat through 2029, near 3.5 (95% range 0.05–6.9). A 5-year backtest shows a typical error of ±20.9%, with 100% of held-out values landing inside the 95% band.

-2%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 →
3.5Projected 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 →
0.05–6.995% 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 →
±20.9%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 2029, near 3.5 (95% range 0.05–6.9). A 5-year backtest shows a typical error of ±20.9%, 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 →
20253.70.277.2
20263.70.227.1
20273.60.167.1
20283.60.117.0
20293.50.056.9

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
Shaftsbury1520241966
Marlboro820241966
Hardwick720241969
North Pownal620181967
S Wallingfrd620221966
W Rutland620241966
Hinesburg619941971
Fletcher520241973
Bristol520181995
Stratton420241966
East Calais420241966
Newbury420041986
Stowe420241988
Middlesex320241968
Landgrove220241966
Gaysville220211966
Post Mills220221966
St Johnsbury220241970
East Haven220241966
Newbury 2220222005
S Reading120241966
Northfld Fls120211980
Greensboro120241967
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 2026-05-22.