Also known as the brown shark, the sandbar shark is a stocky shark that visits the grassy shallows of the lower and middle Chesapeake Bay in summer and autumn.
The sandbar shark has a brownish or dark gray body with a whitish belly. It has a rounded snout and triangular, saw-like teeth. It has a tall, triangular dorsal fin that increases its swimming stability, and a thick, narrow ridge of skin runs along its back between its two dorsal fins. Adults reach seven feet in length, but the juveniles that are found in the Chesapeake Bay are two to three feet long.
Sandbar sharks inhabit coastal waters. They are often found in harbors, bays and the mouths of rivers, preferring protected waters and smooth, sandy bottoms. They are seldom seen at the water's surface and never move into freshwater.
Large schools of juvenile sandbar sharks visit the Chesapeake Bay in summer and autumn. As water temperatures cool, sharks move into warmer, southern waters. They are ost common in the Virginia portion of the Bay, although some travel northward into Maryland waters. Along North America's Atlantic coast, their range extends from Massachusetts to southern Brazil.
Sandbar sharks feed on bottom-dwelling fish and invertebrates. In the Chesapeake Bay, juveniles often feed on blue crabs.
Adults have few predators. Juveniles may be preyed upon by bull sharks and other large sharks.
Females give birth every other year; they are pregnant for eight to 12 months before giving birth between June and August to eight to 10 live young. Juveniles remain in shallow waters until late autumn, when they form schools and move to warmer, southern waters. Males can live up to 15 years, while females can live as long as 21 years.