Common Name: bull shark 



Scientific Name: Carcharhinus leucas 



Other Common Names: cub shark, requiem taureau 



(French), tiburon sarda (Spanish) (Fischer 1978). 



Classification (Robins et al. 1991) 



Phylum: Chordata 



Class: Chondrichthyes 



Order: Lamniformes 



Family: Carcharhinidae 



Value 



Commercial : The bull shark is becoming more impor- 

 tant in the commercial shark fishery of the Gulf of 

 Mexico as the market demand for sharks increases 

 (Branstetter pers. comm., NOAA 1992, NMFS 1993). 

 The flesh is edible, but it is primarily used for fish meal. 

 The hide is processed into leather and has good quality 

 (Castro 1983, NOAA 1992). This species was once 

 sought for its liver which contains large amounts of 

 vitamin A; however, synthetic substitutes have re- 

 duced the demand for this product (Fischer 1978, 

 NOAA 1 992, NMFS 1 993). Bull sharks will take almost 

 any bait, but may prefer shark or ray. Recently, many 

 Gulf of Mexico shrimp fishermen have changed to 

 longline rigs to catch sharks because of the high export 

 demand for shark fins. A Fishery Management Plan 

 (FMP) has been developed for sharks in the western 

 Atlantic, Caribbean Sea, and Gulf of Mexico (NMFS 

 1993). Some of the features of this plan include an 

 annual permit required for commercial shark fishing 

 vessels in the U.S. exclusive economic zone, and an 

 annual quota of 2,436 mt dressed weight for large 

 coastal species during the 1993 fishing year. Future 

 quotas will be based on the shark fishery rebuilding 

 program (NMFS 1993). 



Recreational : In general, shark populations in the Gulf 

 of Mexico and Atlantic waters of the southeast U.S. are 

 suffering from overfishing to which they are especially 

 vulnerable (NOAA 1992). Most sharks caught by 

 recreational anglers are released or discarded, but 

 some are used as mounted trophies or for home 

 consumption. In the Gulf of Mexico, the bull shark 

 comprises 7% by number and 11% by weight of the 

 sharks caught by recreational fishermen (Casey and 

 Hoey 1985). The recreational bag limit is four sharks 

 per boat per trip (NMFS 1 993). 



Indicator of Environmental Stress : This species is not 

 typically used in studies of environmental stress, but 

 monitoring by the Florida Department of Health and 

 Rehabilitative Services has shown high concentra- 

 tions of mercury present in shark flesh sold in the retail 

 market (NMFS 1993). 



Ecological : Sharks are often studied as top trophic 

 level predators (Casey and Hoey 1 985). The bull shark 

 is a top trophic level carnivore in many estuarine 

 systems, and is one of the most common species of 

 inshore sharks in the Gulf of Mexico (Casey and Hoey 

 1985, Shipp 1986). 



Range 



Overall : This is a cosmopolitan species in both tropical 

 and subtropical areas with range extensions into some 

 temperate regions. In the western Atlantic, it extends 

 from Cape Cod, Massachusetts to southern Brazil, 

 including Bermuda, Gulf of Mexico, and Caribbean 

 islands (Fischer 1978, Lee et al. 1980, Garrick 1982). 

 It is most abundant in Gulf of Mexico and Caribbean 

 Sea (Garrick 1982, Castro 1983). In the Pacific, it is 

 known from Anacapa Island off the California coast to 



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