BirdAnalyst
Species · New Jersey · BBS 2025 Release · 1966–2024

Great Horned Owl Population Trend in New Jersey

All statesGeneralists

Great Horned Owl in New Jersey has surged: up 152% on the route-weighted index since 1981.

+152%Since 1981TrendPercent 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 →
22Routes 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 →
28YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Great Horned Owl Trends in New JerseyNotable 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 →

Great Horned Owl has surged in New Jersey: up 152% on the route-weighted index since 1981.

Great Horned Owl Population Forecast in New Jersey

If the recent trend holds, Great Horned Owl in New Jersey is projected to stay roughly flat through 2023, near 0.10 (95% range 0.00–0.27). A 5-year backtest shows a typical error of ±58.5%, with 100% of held-out values landing inside the 95% band.

-2%Change by 2023TrendPercent 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 →
0.10Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2795% 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 →
±58.5%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, Great Horned Owl in New Jersey is projected to stay roughly flat through 2023, near 0.10 (95% range 0.00–0.27). A 5-year backtest shows a typical error of ±58.5%, with 100% of held-out values landing inside the 95% band.19762023
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 →
20190.110.000.27
20200.110.000.27
20210.100.000.27
20220.100.000.27
20230.100.000.27

Great Horned Owl Survey Routes in New Jersey

Routes recording Great Horned Owl in New Jersey.
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 →
Holmansville319961986
Dover320011994
Kemah Lake220171984
Pottersville220141984
Gillette220182014
Greenwich120061991
Six Points120121994
Albion119911991
Sandbrook120011986
New Bedford119841981
Croton120011984
Robbinsville119761976
Hope119891988
Bloomsbury119921992
High Point120001988
Friendship120111983
Pomona120021982
Spraguetown119831979
Pedricktown 2120142014
Cape May Ch119951995
Pedricktown120062006
Winslow120021990

Great Horned Owl Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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