The Florida everglade kite, Rostrhamus sociabilis plumbeus, though reduced in numbers to hardly more than 20, still has a chance to survive. This northern-most subspecies is found only in southern Florida where its continued existence depends on the fresh-water marsh snail Pomacea paludis, its only food. Preservation of some suitable marsh areas, as in Loxahatchee National Wildlife Refuge, is essential to the survival of this endangered species.