WatchList Species Account for
the list as a Red List Species
Photo: Peter La Tourrette
© California Academy of Sciences
The elusive Black Rail breeds in a few
locations in coastal marshes from Connecticut to Florida,
along the Gulf Coast from Peninsular Florida to Texas, with
sporadic records from the interior (Michigan and Kansas),
though no nests have been confirmed in many years. In California
breeds around San Francisco Bay area and on the lower Colorado
River, though there is a paucity of recent records from the
latter; few still resident at Mittry Lake, Arizona. There
are also populations in the Caribbean, in Central America,
and in northern South America. Populations in the latter regions
may involve separate species.
The rail breeds in two types of marsh:
in coastal salt marsh with Spartina species and and in freshwater
marshs with bulrushes. In California tolerates a greater degree
of tidal flooding so long as vegetation cover is available
for escape during extreme high tides to avoid predation by
herons. The California population is resident but in the east
the birds probably move south along the coast after breeding.
It may use wet meadows or agricultural areas during migration.
Though population sizes are not known, more than 6,000 were
estimated for San Pablo Bay, California in 1983.
throughout the species' range has been severe during the past
century and the Lower Colorado River population is estimated
to have declined 30% between 1973 and 1989, with an apparent
concurrent range shift to Mittry Lake, Arizona. Between 1850
and 1973, about 95% of San Francisco Bay's tidal marshes were
diked or filled. Breeding records in the midwest have dropped
to zero with no confirmation since 1932. In the east, the
species has been lost as a breeder in Massachusetts since
the 1930s and may have declined elsewhere.
The loss of saltmarsh, and ditching to
control mosquitos are the primary threats to the species.
The spread of the introduced common reed Phragmites australis
may also be reducing habitat quality. As the species prefers
drier areas, often along the edge of marshland, it is more
susceptible to burning and grazing pressure than other rails.
In California, there has been massive habitat loss for salt
production, agriculture, and urban development. Sea-level
rise with global climate change also presents a real risk
for this species.