A lifeguard at Siesta Beach holds up a tunicate that washed ashore. Some people have mistaken tunicates for oil patties.
Sarasota, Florida - Mote Marine Laboratory in Sarasota has received questions about what looks like darkened oil blobs on Siesta Beach.
It's not oil!
It's a marine animal called a tunicate.
"Believe it or not, these amorphous blobs are actually living organisms called tunicates and their shapes, sizes and even their coloration can vary widely," said Hayley Rutger at Mote Marine Laboratory.
Photo Gallery: Pictures of tunicates washed up on shore
Mote has received so many questions about the Disaster in the Gulf that they've posted a list of them, along with answers, on their website.
Some 78 species of tunicates have been documented in the Gulf of Mexico. They're invertebrate species that have characteristics of backboned critters including a notochord, dorsal nerve cord and pharyngeal slits. In adults, these features become simple ganglion.
As larva, tunicates can swim and look like tadpoles, but once they grow up, they're immobile filter feeders. Adult tunicates have sack-shaped bodies with two siphons they use to filter water. The hard covering on their bodies is called a tunic.
You may also know them by their other name: sea squirt.
Janie Porter, 10 Connects