Sandbar Shark Carcharhinus plumbeus

This species gets its common name from the sandy and muddy flats, bays and estuaries in which it's commonly found. Also known as the “brown shark along the U.S. Atlantic coast,” this species is recognized by its large first dorsal fin, large pectoral fins and mid-dorsal ridge. Sandbar sharks favor smooth substrate over coral reefs or other rough-bottom areas of the ocean. They are the most common species of shark found in the Chesapeake Bay! Like many other shark species, sandbar sharks give birth to live young. Female sandbars have a range of about one to 14 pups per litter. This species reaches sexual maturity at around 16 years of age (but some females may mature as late as 29 years or more) and their average gestation period is about 12 months. Females reproduce every other year. The diet of a sandbar shark typically consists of small bony fishes like menhaden, croaker, snapper, mojarras, as well as crustaceans such as crabs and shrimp. Other prey include smaller species of shark like bonnetheads, octopuses, rays, and some species of crustaceans such as shrimp and crab. They reach about 20 to 24 inches long at birth, and can grow up to 8 feet. Sandbar sharks occur in warm temperate to tropical coastal waters around the globe. In the western Atlantic, they range from New England to Brazil. Globally, directed shark fisheries, bycatch and shark finning have taken a toll on sandbar shark populations. They are annually either the first or second most abundant species represented in the Atlantic large coastal shark fishery. Given the prominent size of their fins, sandbar sharks are valued highly in some of the world’s largest fish markets. As a result of the population’s quick decline in recent years, the sandbar shark has been listed as vulnerable on the IUCN Red List. Besides humans, sandbar sharks have very few predators. Their slow growth, late sexual maturity and small number of offspring make this species very sensitive to overfishing and habitat degradation. The sandbar shark (Carcharhinus plumbeus) is a species of requiem shark, and part of the family Carcharhinidae, native to the Atlantic Ocean and the Indo-Pacific. It is distinguishable by its very high first dorsal fin and inter-dorsal ridge. It is not to be confused with its similarly named shark cousin, the sand tiger shark, Carcharius taurus. The sandbar shark is also called the thickskin shark or brown shark. It is one of the biggest coastal sharks in the world, and is closely related to the dusky shark, the bignose shark, and the bull shark. Its dorsal fin is triangular and very high and it has very long pectoral fins. Sandbar sharks usually have heavy-set bodies and rounded snouts that are shorter than the average shark's snout. Their upper teeth have broadly uneven cusps with sharp edges. Its second dorsal fin and anal fin are close to the same height. Females reach sexual maturity around the age of 13 with an average fork-length (tip of the nose to fork in the tail) of 154.9 cm, while males tend to reach maturity around age 12 with an average fork-length of 151.6 cm. Females can grow to 2–2.5 m (6.6-8.2 ft), males up to 1.8 m (5.9 ft). Its body color can vary from a bluish to a brownish grey to a bronze, with a white or pale underside. Sandbar sharks swim alone or gather in sex-segregated schools that vary in size. The sandbar shark, true to its nickname, is commonly found over muddy or sandy bottoms in shallow coastal waters such as bays, estuaries, harbors, or the mouths of rivers, but it also swims in deeper waters (200 m or more) as well as intertidal zones. Sandbar sharks are found in tropical to temperate waters worldwide; in the western Atlantic they range from Massachusetts to Brazil. Juveniles are common to abundant in the lower Chesapeake Bay, and nursery grounds are found from Delaware Bay to South Carolina. Other nursery grounds include Boncuk Bay in Marmaris, Muğla/Turkey and the Florida Keys. Natural predators are the tiger sharks, and rarely great white sharks. The sandbar sharks prey on fish, rays, and crabs. Sandbar sharks are viviparous. The embryos are supported in placental yolk sac inside the mother. Females have been found to exhibit both biennial and triennial reproductive cycles, ovulate in early summer, and give birth to an average of 8 pups, which they carry for 1 year before giving birth. Sandbar sharks have been disproportionately targeted by the U.S. commercial shark fisheries in recent decades due to their high fin-to-body weight ratio, and U.S. fishing regulation requiring carcasses to be landed along with shark fins. In 2008, the National Marine Fisheries Service banned all commercial landings of sandbar sharks based on a 2006 stock assessment by SEDAR, and sandbar sharks were listed as vulnerable, due to overfishing. Currently, there are a small number of specially permitted vessels fishing for sandbars sharks for the purpose of scientific research. All vessels in the research fishery are required to carry an independent researcher while targeting sandbars. The longevity of the sandbar shark is typically 35-41 years. In spite of their large size and similar appearance to other dangerous sharks like Bull Sharks, there are very few, if any attacks attributed to Sandbar Sharks and so they are considered not to be dangerous to people. As a result, they are considered one of the safest sharks to swim with and are popular sharks for aquariums.