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

Barred Owl Population Trend in Maryland

All statesBirds of prey

Barred Owl in Maryland has surged: up 455% on the route-weighted index since 1968.

+455%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 →
61Routes 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 Barred Owl Trends in MarylandNotable 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 increasecomputed 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 →

Barred Owl has surged in Maryland: up 455% on the route-weighted index since 1968.

Barred Owl Population Forecast in Maryland

If the recent trend holds, Barred Owl in Maryland is projected to stay roughly flat through 2030, near 0.22 (95% range 0.09–0.35). A 5-year backtest shows a typical error of ±44.4%, with 80% of held-out values landing inside the 95% band.

-7%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 →
0.22Projected 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 →
0.09–0.3595% 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 →
±44.4%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 Maryland is projected to stay roughly flat through 2030, near 0.22 (95% range 0.09–0.35). A 5-year backtest shows a typical error of ±44.4%, with 80% 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 →
20260.210.080.34
20270.210.080.35
20280.220.080.35
20290.220.090.35
20300.220.090.35

Barred Owl Survey Routes in Maryland

Routes recording Barred Owl in Maryland.
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 →
Beltsville320041966
Cokesbury320241967
Newark319741966
Finzel320242010
Smithsburg220131978
Silver Spg219871987
Pleasant Val220171989
Bachman Mill220032000
Cheltenham219881974
Melitota220141998
Harmony219861971
Golden Hill220111976
Forest Grove220182013
Davidsnville220251991
Floyd120232023
Mt Nebo119891977
Vindex120081975
Oldtown120241981
Potomac Park120241993
Williamsport120251972
Wolfsville120231980
Emmitsburg120252011
Olney120251978
Norwood119781976
Warfieldsbrg120052005

Barred Owl Population Trend in Other States

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

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