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

Great Horned Owl Population Trend in Massachusetts

All statesGeneralists

Great Horned Owl in Massachusetts has increased: up 32% on the route-weighted index since 1991.

+32%Since 1991TrendPercent 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 →
11Routes 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 →
14YearsYears 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 MassachusettsNotable 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 Great Horned Owl in Massachusetts. See the full index history below.

Great Horned Owl Survey Routes in Massachusetts

Routes recording Great Horned Owl in Massachusetts.
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 →
E Dennis219911991
Belchertown220242022
Wellfleet119911971
Maynard120212021
Wellfleet 2120242024
Mansfield119921992
Warren119991987
S Barre120232018
Cummington119911991
Chesterfield120062006
Warren 2120242011

Great Horned Owl Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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