A subspecies of the clapper rail found only in the Florida Keys, the mangrove clapper rails are genetically distinct from clapper rail population found elsewhere in the state. Mangrove clapper rails are highly secretive birds, typically remaining hidden among the grasses of the high tidal marshes where they nest. During periods of low tide, rails venture from their cover to forage for insects, crabs and mollusks along the exposed mudflats. While seldom seen, clapper rails are often heard. Their loud call, a harsh “kek-kek-kek” note, often elicits a clattering chorus of responses.
Mangrove clapper rails nest in the higher portions of tidal salt marshes or tall cordgrass that blocks inundation from high tide.
The mangrove clapper rail is considered highly vulnerable to climate-related threats, most notably sea level rise. Estimates indicate that the clapper rail could lose up to 100% of usable habitat to sea level rise. Manmade and natural barriers, such as development, may prevent the mangrove clapper rail from extending its range into new areas of suitable habitat under climate change. Additionally, the mangrove clapper rail is highly dependent on available fiddler crab, with other prey only supplementing the bird’s diet. This degree of specialty may limit this bird’s ability to adapt to new sources of food in shifting ecological communities due to climate change. As a subspecies, the mangrove clapper rail is also at risk of genetic swamping if it moves and interbreeds with mainland populations under the shifting conditions of climate change.
More information about general climate impacts to species in Florida.
The overall vulnerability level was based on the following assessment(s):
The primary factors contributing to vulnerability of the mangrove clapper rail are sea level rise, erosion, presence of barriers, changes in temperature regime, habitat fragmentation, changes in salinity, and runoff and storm surge.