Bird Conservation Region 26

Mississippi Alluvial Valley

An ecological region spanning Arkansas, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, with 73 survey routes. BCRs are the natural unit for bird trends.

What Is Moving Here

long arc declinecomputed index

Bank Swallow has collapsed in Mississippi Alluvial Valley: down 97% on the route-weighted index since 1980.

long arc increasecomputed index

Cliff Swallow has surged in Mississippi Alluvial Valley: up 155× on the route-weighted index since 1995.

long arc declinecomputed index

Laughing Gull has collapsed in Mississippi Alluvial Valley: down 95% on the route-weighted index since 1989.

long arc increasecomputed index

Snowy Egret has surged in Mississippi Alluvial Valley: up 28× on the route-weighted index since 1975.

long arc declinecomputed index

Chuck-will's-widow has collapsed in Mississippi Alluvial Valley: down 93% on the route-weighted index since 1969.

long arc increasecomputed index

Black-bellied Whistling-Duck has surged in Mississippi Alluvial Valley: up 20× on the route-weighted index since 2008.

How Guilds Are Faring

Survey Routes

Species By Family

Osprey Pandionidae

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