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

Barred Owl Population Trend in Maine

All statesGeneralists

Barred Owl in Maine has increased: up 33% on the route-weighted index since 1975.

+33%Since 1975TrendPercent 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 →
45Routes 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 →
42YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Barred Owl 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 →

No notable trend signals for Barred Owl in Maine. See the full index history below.

Barred Owl Population Forecast in Maine

If the recent trend holds, Barred Owl in Maine is projected to fall about 46% by 2029 — from 0.21 in 2024 to a central estimate of 0.11 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±74.3%, with 60% of held-out values landing inside the 95% band.

-46%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 →
0.11Projected 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 →
0.00–0.2595% 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 →
±74.3%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, Barred Owl in Maine is projected to fall about 46% by 2029 — from 0.21 in 2024 to a central estimate of 0.11 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±74.3%, with 60% 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 →
20250.110.000.25
20260.110.000.25
20270.110.000.25
20280.110.000.25
20290.110.000.25

Barred Owl Survey Routes in Maine

Routes recording Barred Owl 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 →
Washburn319951994
Harmony219881988
Aurora220041993
Northfield 2120162014
Biddeford120022002
Kittery Pt120212021
Newcastle120071988
Wilson Mills120102006
Bethel120081979
Greenwood120242005
Reeds120062003
South Arm120091975
Otisfield Gr119821982
Hartford120231977
Bowdoin Ctr120211979
East Troy120181992
Freedom120212005
Brooks120061990
Hermon119731967
Hancock119761976
Castine119861986
Cooper120041980
Deblois119931980
Northfield119791979
Moose River119881988

Barred Owl Population Trend in Other States

alabamaalaskaarkansascaliforniaconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawashingtonwest-virginiawisconsin

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