State · BBS 2026 Release · 1966–2025
Illinois Breeding Birds
185 species recorded across 105 survey routes, 1966 to 2025. Browse by family or guild below.
Illinois Bird Population TrendsNotable 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 →
Western Meadowlark has collapsed in Illinois: down 98% on the route-weighted index since 1968.
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 →
Cliff Swallow has surged in Illinois: up 170× on the route-weighted index since 1969.
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 →
Bobolink has collapsed in Illinois: down 97% on the route-weighted index since 1968.
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 →
Turkey Vulture has surged in Illinois: up 55× on the route-weighted index since 1972.
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 →
Loggerhead Shrike has collapsed in Illinois: down 97% on the route-weighted index since 1968.
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 →
Blue Grosbeak has surged in Illinois: up 46× on the route-weighted index since 1968.
How Bird Guilds Are Faring in IllinoisGuild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology →
Illinois Bird Survey Routes
Browse Illinois Birds By FamilyTrendPercent 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 →
Each species links to its trend in Illinois.
Hawks, Eagles & Kites Accipitridae
Larks Alaudidae
Kingfishers Alcedinidae
Ducks, Geese & Waterfowl Anatidae
Swifts Apodidae
Herons, Egrets & Bitterns Ardeidae
Waxwings Bombycillidae
Nightjars & Nighthawks Caprimulgidae
Cardinals & Grosbeaks Cardinalidae
Plovers & Lapwings Charadriidae
Falcons & Caracaras Falconidae
Finches Fringillidae
Cranes Gruidae
Swallows & Martins Hirundinidae
Blackbirds & Orioles Icteridae
Shrikes Laniidae
New World Quail Odontophoridae
Osprey Pandionidae
Chickadees & Titmice Paridae
Wood-Warblers Parulidae
American Redstart +72%Black-and-white Warbler -82%Blue-winged Warbler +37%Cerulean Warbler -49%Common Yellowthroat +132%Hooded Warbler -8%Kentucky Warbler +206%Louisiana Waterthrush +398%Northern Parula 27×Ovenbird -36%Pine Warbler -9%Prairie Warbler +206%Prothonotary Warbler +222%Worm-eating Warbler +31%Yellow Warbler +169%Yellow-throated Warbler +217%
New World Sparrows Passerellidae
Cormorants Phalacrocoracidae
Woodpeckers Picidae
Grebes Podicipedidae
Gnatcatchers Polioptilidae
Starlings & Mynas Sturnidae
Hummingbirds Trochilidae
Tyrant Flycatchers Tyrannidae
Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.