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

Chuck-will's-widow Population Trend in Illinois

All statesAerial insectivores

Chuck-will's-widow in Illinois has collapsed: down 77% on the route-weighted index since 1971.

-77%Since 1971TrendPercent 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 →
4Routes 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 →
17YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Chuck-will's-widow Trends in IllinoisNotable 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 declinecomputed 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 →

Chuck-will's-widow has collapsed in Illinois: down 77% on the route-weighted index since 1971.

Chuck-will's-widow Survey Routes in Illinois

Routes recording Chuck-will's-widow in Illinois.
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 →
Delwood320191971
Sandusky119931993
Bremen119861969
Belknap119861970

Chuck-will's-widow Population Trend in Other States

alabamaarkansasdelawarefloridageorgiaindianakansaskentuckylouisianamarylandmississippimissourinebraskanew-jerseynorth-carolinaohiooklahomasouth-carolinatennesseetexasvirginiawest-virginia

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