Each night from the middle of April through about May
23, the marshes and barrier islands of Georgia and South
Carolina host a large proportion of the whimbrel population
of the Atlantic Flyway, perhaps 10,000 to 15,000 individual
birds. As yet biologists have not been able to get a precise
estimate. These extreme flyers come from the Caribbean and
northern South American coast to “stage” during migration
to their nesting grounds in Hudson Bay lowlands and low
Arctic beyond. During this pause in migration, they feed
throughout each day, scarfing fiddler crabs by the hundreds,
and then congregate at specific sand spits at night. These
large distinct shorebirds find roosts as far from the tree line
as possible, where the open sandbars at the mouths of tidal
rivers give them some distance from the super predators,
great horned owls. Whimbrels depart again for the marshes
as soon as the first gray light of dawn brings definition to
the low-lying sands. They are here in South Carolina on a
mission, to feed for about five weeks, to get really fat and to
build muscle before continuing north.
Saltmarshes are really an elaborate mix of salinities and sediments that create a diverse array of micro-habitats valuable for
producing shorebird foods and a visually stunning pattern from above.
The foods they seek as body-fuel for the next migratory
jump are in great abundance on this part of the Atlantic
because the habitat is so good. This immense basin, known
as the “Georgia Bight,” supports a very wide intertidal zone.
The width of this area starts at the high tide line where the
saltmarsh meets the high ground of the mainland and spans
east to the outermost shoals at the mouths of inlets and tidal
rivers. This section of coast has a larger tidal span between
high and low tide than areas immediately to the north or
south, has a shallow slope that extends well off shore, and is
brimming with the sediments from free-flowing rivers that
are loaded with the favorite foods of shorebirds.
SUMMER/FALL 2017 • VOLUME 38
The saltmarshes, tidal creeks, and expansive shoals
stretching into the ocean all drain and flood twice a day.
Each dropping tide exposes the fiddler crabs, polychaete
worms, amphipods, ghost shrimp, and small clams upon
which shorebirds depend. The birds that have been resting in
flocks at roosting sites in the day follow the tide out, finding
and consuming their preferred and most abundant prey
items. Large numbers of many species of shorebirds travel
to the Georgia Bight once and sometimes twice per year
during critical phases of migration. Other than whimbrel,
there are large numbers of dunlin, short-billed dowitcher,
ruddy turnstone, red knot, semipalmated sandpiper, willet,
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