Sunday, October 7, 2012

Fiddler Crabs

Fiddler crabs in the salt marsh. Click to enlarge.
Summer has ended. Nights are cooling. Days are shorter. The kids have gone back to school. And the fiddler crabs will soon disappear.

The fiddler crabs in the photographs live in the muddy salt marsh at Forsythe National Wildlife Refuge on the New Jersey shore near Atlantic City. At low tide they forage for bits of decayed plant material. When the tide comes in, they retreat into underground burrows, plugging the entrances with mud. They stay holed up there until the tide goes out. If you watch the mud flats as the water withdraws you will see holes appear and crabs emerge. From spring until autumn, at least. But when the weather gets too cold for them, fiddler crabs retreat into their burrows, plug them up, and stay out of sight until spring. The ones at Forsythe will do that soon -- the high temperature in Atlantic City today was only 57 degrees.

Mud fiddlers can be found along the Atlantic coast from Florida to Massachusetts. Their shells are square with rounded edges and about two inches wide. Crabs with one giant claw are males. The large claw can be on either side.  Rival males fight each other with them. Big claws also attract females; amorous male fiddlers stand next to their burrows and wave the claw provocatively. When a female approaches, the male taps his claw on the ground, or may slip into the burrow entrance and bang his claw. That can be irresistible to a female fiddler crab. If she is receptive, she will go into the burrow and they will mate.

They remind me of a hippie song from the 1960's by Donovan Leitch -- The Tinker and the Crab. In part:

...Down where young gulls dance
Driftwood lying, drying for the fire
Yellow beak and sleek
Now the gulls are crying, flying higher
Out from the sea came a little green crab
Taking the sun
The morning being very drab
Old rusted cans
Pebbles 'bedded in the sand
Stand and stare


2 comments:

  1. Please attend the 3rd Annual New York Wildlife Conservation Film Festival in Manhattan November 7-10. For a complete list of films and speakers visit our website: www.WCFF.org

    This is a unique conservation, cultural, education and entertainment event.

    ReplyDelete
    Replies
    1. Hi Lillian,

      Sounds good! Thanks for the link. I will check it out.

      Delete