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

Olive-sided Flycatcher Population Trend in Maine

All statesAerial insectivores

Olive-sided Flycatcher in Maine has collapsed: down 90% on the route-weighted index since 1969.

-90%Since 1969TrendPercent 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 →
68Routes 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 →
53YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Olive-sided 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 →

Olive-sided Flycatcher has collapsed in Maine: down 90% on the route-weighted index since 1969.

Olive-sided Flycatcher Population Forecast in Maine

If the recent trend holds, Olive-sided Flycatcher in Maine is projected to fall about 21% by 2029 — from 0.05 in 2024 to a central estimate of 0.04 (95% range 0.00–0.64). A 5-year backtest shows a typical error of ±170.5%, with 100% of held-out values landing inside the 95% band.

-21%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 →
0.04Projected 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 →
0.00–0.6495% 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 →
±170.5%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, Olive-sided Flycatcher in Maine is projected to fall about 21% by 2029 — from 0.05 in 2024 to a central estimate of 0.04 (95% range 0.00–0.64). A 5-year backtest shows a typical error of ±170.5%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.090.000.68
20260.080.000.67
20270.070.000.66
20280.050.000.65
20290.040.000.64

Olive-sided Flycatcher Survey Routes in Maine

Routes recording Olive-sided 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 →
Pillsbury Pd1319681968
Telos520061995
Baxter419881982
Reeds320142014
Northfield319811977
Washburn319961980
Topsfield219921978
Hancock219761969
Castine219971983
Cooper219811978
Seboomook Lk220141972
Wytopitlock219821976
Ludlow219931968
Horse Mtn220111983
St David220051982
Heron Lake220031983
Stacyville220212021
Northfield 2120131992
Kittery Pt119781978
Newcastle119881986
Wilson Mills120241983
Bethel120191979
Nesowadnehun119971991
Greenwood119791979
South Arm119921975

Olive-sided Flycatcher Population Trend in Other States

alaskaarizonacaliforniacoloradoidahomarylandmassachusettsmichiganminnesotamontananevadanew-hampshirenew-mexiconew-yorknorth-carolinaohiooregonpennsylvaniasouth-dakotautahvermontwashingtonwest-virginiawisconsinwyoming

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