This class comprises the sharks, rays, skates, and chimaeras. In the salt marsh-tidal creek system you will find a few different species of sharks and rays. They are characterized by having jaws and a skeleton made of cartilage, like what our ear lobes are made of, instead of bone. Instead of having an operculum covering their gills, sharks and rays have 5-7 visible gill slits on the sides of their head. Unlike bony fish, the cartilaginous fish do not have a swim bladder, so must move continuously or else they will sink.
One characteristic unique to cartilaginous fishes is the ampullae of Lorenzini. If seen, the ampullae will look like small dots around the mouth or nose of a shark or ray. They are actually sensory cells that are able to detect small electric charges given off by their prey. These animals are not naturally aggressive, but when walking through a tidal creek it may be a good idea to do the “sting ray shuffle” to warn them that you are coming!
Dasyatis sabina
Disk-shaped, flat body, dark gray or light brown above and lighter below; snout is elongated
NJ to the Gulf of Mexico
Up to 2ft (.5m) in disk width
Shallow estuaries, tidal creeks
Spiracles on the top are often mistaken for another set of eyes but they actually take in water while buried in sediment
Rhizoprionodon terraenovae
Sphyrna tiburo
Shovel-shaped head with eye on either side; gray-brown dorsally and white ventrally; mouth on the bottom
Atlantic coast of the U.S. to Brazil, and CA to Ecuador
Up to 4ft (1m) in length
Warm estuaries, often in tidal creeks
Females move further into shallow water than males do, but scientists do not yet understand why