The Cape Sable Seaside Sparrow (Ammodramus maritimus mirabilis) is a sub-species of Seaside Sparrow endemic to southern Florida. The largest populations are found in Taylor Slough in Everglade National Park and in the Big Cypress Swamp. The species is considered endangered due to habitat loss from vegetation changes, fire, development, alteration of water flow, and hurricanes.
Cape Sable Seaside Sparrows are about 13 centimeters (5 inches) long. The back is dark olive-gray and the tail and wings are olive-brown. Adults are light gray on the belly to almost white with dark olive-gray streaks on the breast and sides.
The Cape Sable Seaside Sparrow lives on the prairies of the Everglades and the Big Cypress Swamp. (Prairies are grasslands subject to frequent fires which limit the growth of trees. Dry prairies flood after heavy rains. Wet prairies are flooded from two to five months each year.) Specific habitats for the sparrows on the prairies are stands of muhly grass (Muhlenbergia filipes), short sawgrass (Cladium jamaicensis), tall, clumped cordgrass, and relatively spares low cordgrass.