Drivers along S.C. 170 in Okatie have been faced with an ominous sign.

The digital billboard flashes with two shrimp with blackened heads suspended above a single black brushstroke. No words describe the meaning of the sparse image that appears to form a sad face.

A call to the billboard company has solved the mystery.

Adams Outdoor Advertising, the billboard's owner, posted the images in the Charleston, Charlotte and Beaufort areas to raise awareness of the ongoing oil spill in the Gulf of Mexico.

The campaign, which will continue indefinitely, appears to be drawing the attention of curious motorists: Mike Bruns, the company's sales manager in Beaufort, estimated he has received more than 30 calls about the Okatie sign.

The image was designed by one of the company's art directors, who is from New Orleans and works in Florence.

The Atlanta-based company, which has devoted part of its website to the campaign, does not seek to take a political position but wants its ads to convey the sadness of the spill, according to a statement on the site.

Read the complete story at islandpacket.com