State · BBS 2025 Release · 1966–2024
Connecticut Breeding Birds
163 species recorded across 20 survey routes, 1966 to 2024. Browse by family or guild below.
Connecticut 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 →
Eastern Meadowlark has collapsed in Connecticut: 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 →
Carolina Wren has surged in Connecticut: up 33× on the route-weighted index since 1976.
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 →
Brown Thrasher has collapsed in Connecticut: 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 →
Pine Warbler has surged in Connecticut: up 32× on the route-weighted index since 1980.
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 →
Field Sparrow has collapsed in Connecticut: down 96% 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 →
Red-bellied Woodpecker has surged in Connecticut: up 24× on the route-weighted index since 1979.
How Bird Guilds Are Faring in ConnecticutGuild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology →
Connecticut Bird Survey Routes
Browse Connecticut 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 Connecticut.
Hawks, Eagles & Kites Accipitridae
Kingfishers Alcedinidae
Ducks, Geese & Waterfowl Anatidae
Swifts Apodidae
Herons, Egrets & Bitterns Ardeidae
Waxwings Bombycillidae
Nightjars & Nighthawks Caprimulgidae
Cardinals & Grosbeaks Cardinalidae
New World Vultures Cathartidae
Treecreepers Certhiidae
Plovers & Lapwings Charadriidae
Falcons & Caracaras Falconidae
Swallows & Martins Hirundinidae
Blackbirds & Orioles Icteridae
New World Quail Odontophoridae
Osprey Pandionidae
Wood-Warblers Parulidae
American Redstart +38%Black-and-white Warbler -42%Black-throated Blue Warbler +13%Black-throated Green Warbler -29%Blackburnian Warbler -9%Blue-winged Warbler -76%Canada Warbler -85%Cerulean Warbler +43%Chestnut-sided Warbler -62%Common Yellowthroat -20%Hooded Warbler +234%Louisiana Waterthrush +235%Magnolia Warbler +20%Northern Parula +101%Northern Waterthrush -54%Ovenbird +70%Pine Warbler 32×Prairie Warbler -73%Worm-eating Warbler +568%Yellow Warbler +103%
New World Sparrows Passerellidae
Old World Sparrows Passeridae
Cormorants Phalacrocoracidae
Woodpeckers Picidae
Gnatcatchers Polioptilidae
Starlings & Mynas Sturnidae
Hummingbirds Trochilidae
Thrushes Turdidae
Tyrant Flycatchers Tyrannidae
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.