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

Least Flycatcher Population Trend in Maine

All statesAerial insectivores

Least Flycatcher in Maine has fallen sharply: down 60% on the route-weighted index since 1968.

-60%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 →
78Routes 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 MaineNotable 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 Maine: down 60% on the route-weighted index since 1968.

Least Flycatcher Population Forecast in Maine

If the recent trend holds, Least Flycatcher in Maine is projected to rise about 68% by 2029 — from 1.1 in 2024 to a central estimate of 1.8 (95% range 0.00–4.6). A 5-year backtest shows a typical error of ±133.8%, with 100% of held-out values landing inside the 95% band.

+68%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 →
1.8Projected 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 →
0.00–4.695% 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 →
±133.8%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, Least Flycatcher in Maine is projected to rise about 68% by 2029 — from 1.1 in 2024 to a central estimate of 1.8 (95% range 0.00–4.6). A 5-year backtest shows a typical error of ±133.8%, 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 →
20251.90.004.8
20261.90.004.8
20271.90.004.7
20281.80.004.7
20291.80.004.6

Least Flycatcher Survey Routes in Maine

Routes recording Least Flycatcher in Maine.
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 →
Nesowadnehun2020211990
Warren1319901973
Horse Mtn1320111983
Manchester719951971
Baxter719881977
Washburn720051979
Bowdoin Ctr620131975
Benton619801971
Seboomook Lk620141972
St David620051982
Waite519771977
Baker Lake520091994
Clayton Lake 2520112010
Andover520212010
Reeds420241990
Northfield419811976
Forest Sta420001966
Jefferson420081991
Wilson Mills320241983
Winn320211969
Clayton Lake320081977
Ludlow319981968
Weeks Brook320161995
Telos320061995
Yankeetuladi320091994

Least Flycatcher Population Trend in Other States

alaskaarkansascaliforniacoloradoconnecticutgeorgiaidahoillinoisindianaiowakentuckymarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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