Odd heart-shaped patch of color on South Carolina beach likely was clam mating ritual

An unusual heart-shaped patch of color found on a South Carolina beach was a nest of sea creatures, according to a post by the Town of Kiawah Island, 25 miles south of Charleston.

“Island resident, Barbara, was lucky to find ‘love’ on her beach walk this morning... a coquina nest shaped like a heart,” the town wrote on Facebook on Saturday.

Coquina are small (less than an inch), wedge-shaped clams and stick out in the sand due to “highly variable colors ranging from yellow to red to brown to purple to white,” according to the Tybee Island Marine Science Center.

They are known for burying themselves quickly after washing up, the center says, which begs the question as to why they were seen hanging out in the open Saturday morning.

The answer likely involves the clam version of hanky panky.

They mate in the spring, making it possible to see ”large mats of thousands of coquina tightly compacted together and exposed at low tide,” according to an article in Coastal Review Online.

“Since reproduction is external through the release of eggs and sperm ... this is a mating behavior and increases the chances of fertilization,” the review said. “When the clam is exposed like this it is easy to see their diversity of colors.”

The presence of coquina — dead or alive — is a sign of a healthy beach, the town wrote.

“Kiawah Island is home or a rest stop for many varieties of shorebirds, which many nibble on the coquinas,” the post said.

This story was originally published March 29, 2020 at 9:02 AM with the headline "Odd heart-shaped patch of color on South Carolina beach likely was clam mating ritual."