loose gravel because they are similar to the pebbly scrapes they create in the sand.
Roofs also provide protection from mammalian predators. However, these homes
have a severe drawback—they can get too hot and chicks sometimes become stuck
in melted tar. Specially made boxes can help by providing shelter from the tar and a
better nesting environment.
Amazingly, some least terns have found another answer: nesting on the flat
surfaces of the concrete supports for the Ravenel Bridge in Charleston. Clamshell
pieces dropped on the supports by winter gulls recreate the pebbly feel they like
in their nests. The supports also offer shade for part of the day, freedom from tidal
washovers and an absence of most predators. But even this ingenious solution has a
problem. Newly hatched chicks start to walk long before they can fly, putting those
hatched on bridge supports in a precarious position. Next season, South Carolina
Department of Natural Resources biologists hope to be able to place fences around
the bridge supports to prevent the chicks from falling.
Wherever they nest, females lay one to three jellybean-sized eggs that are light
brown and have dark markings. Both parents share incubation duties, with the
male bringing food to the female while she is sitting on the eggs. After 20–25 days
the eggs hatch and chicks leave the nest within only one or two days. They are able
to fly within about 20 days but remain dependent on their parents for several weeks
afterwards.
In August, least terns have finished their nesting and heed the call to the warmer
climes where they will spend the upcoming months. Later, as days shorten and
winter sets in on Kiawah, we will look forward to that great circle of migration
and life, to the return of spring with its warm sunny days and soft breezes and the
arrival once again of that small, but determined bird, the least tern. NK
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