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

Barred Owl Population Trend in Delaware

All statesGeneralists

Barred Owl in Delaware has surged: up 173% on the route-weighted index since 1970.

+173%Since 1970TrendPercent 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 →
8Routes 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 →
19YearsYears 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 DelawareNotable 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 Delaware: up 173% on the route-weighted index since 1970.

Barred Owl Population Forecast in Delaware

If the recent trend holds, Barred Owl in Delaware is projected to stay roughly flat through 2028, near 0.23 (95% range 0.05–0.42). A 5-year backtest shows a typical error of ±46.8%, with 60% of held-out values landing inside the 95% band.

-7%Change by 2028TrendPercent 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 →
0.23Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.05–0.4295% 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 →
±46.8%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, Barred Owl in Delaware is projected to stay roughly flat through 2028, near 0.23 (95% range 0.05–0.42). A 5-year backtest shows a typical error of ±46.8%, with 60% of held-out values landing inside the 95% band.19672028
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 →
20240.230.040.41
20250.230.040.41
20260.230.040.41
20270.230.050.42
20280.230.050.42

Barred Owl Survey Routes in Delaware

Routes recording Barred Owl in Delaware.
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 →
Frankford219761973
Harrington120211967
Dover119791979
Holleyville119921970
Lowes Xrds119781969
Blackbird120212013
Holleyville 2120152015
Pepperbox 2120232017

Barred Owl Population Trend in Other States

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

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