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South Florida Aquatic Environments About the Different Groups of Fishes About the Anatomy of Fish and Sharks How Fish and Sharks Swim About Fish Adaptations About the Endangered Species Act How to Become a Biologist About Careers In Ichthyology Most Commonly Asked Shark Questions Most Commonly Asked Sawfish Questions Most Commonly Asked Ray and Skate Questions Most Commonly Asked Fish Questions Identification Key to Freshwater Fishes of Peninsular Florida Field Key to Sharks Skates of the Western Gulf of Maine Project Shark Awareness - A Public Outreach Educational Program Shark Fishing in U.S. Territorial Waters Most Commonly Asked Sawfish Questions Sawfish In Peril - PowerPoint file Sawfish Informational Brochure - Acrobat file Sawfish Outreach Boat Ramp/Marina Sign - Acrobat file Sawfish References Sawfish Links Smalltooth Sawfish species profile Largetooth Sawfish species profile Green Sawfish species profile Freshwater Sawfish species profile Dwarf Sawfish species profile Knifetooth Sawfish species profile Chondrichthyes Bibliography Search Freshwater Fishes of Florida References General Fish References Shark References Sawfish References Childrens' Shark Books Stingray Reproduction References Biological Profiles Glossary of Terms Shark Games: Test Your Knowlege! 2003 Open House Photos BIGNOSE SHARK Order - Carcharhiniformes Family - Carcharhinidae Genus - Carcharhinus Species - altimus Taxonomy The bignose shark was described in 1950 as Carcharhinus altimus by Stewart Springer. This specimen used in the description was caught in the Florida Keys. The genus name Carcharhinus is derived from the Greek "karcharos" = sharpen and "rhinos" = nose. Synonyms include Carcharhinus radamae Fourmanoir 1961 and Carcharinus radamae Fourmanoir 1961. Common Names English language common names include bignose shark and Knopp's shark. Other names used to refer to this species are baboso (Spanish), grootneushaai (Afrikaans), grootsnuithaai (Dutch), karcharinos megalorynchos (Greek), marracho baboso (Portuguese), requin babosse (French), squalo naso grande (Italian), tiburón baboso (Spanish), tiburón narizón (Spanish), and tubarão-baboso (Portuguese). Geographical Distribution Bignose sharks are circumglobal in distribution with records in tropical and warm regions. In the western Atlantic Ocean, it occurs from Florida (USA) south to Venezuela while in the eastern Atlantic Ocean it has been reported from Senegal to Ghana including the Mediterranean Sea. Reports from the western Indian Ocean include the Red Sea, Mozambique, South Africa, Madagascar, and India. Distribution in the Pacific Ocean is off China in the west, Hawaii in the central, and Gulf of California, Mexico, Colombia, and Ecuador in the east. World distribution map for the bignose shark Habitat This large offshore species is found near the edges of continental shelves and insular slopes at depths from near the surface to 1,410 feet (430 m). The adults often swim at depths greater than 295 feet (90 m) while the juveniles frequent shallower waters. Biology Bignose illustration source: FAO Species Catalogue, Vol. 4 Part 2 - Sharks of the World · Distinctive Features The bignose shark is large and slender with a long, broad and bluntly pointed snout from which it gets its common name. The well developed nasal flaps are prominent. The interdorsal ridge is high and conspicuous. The pectoral fins are long and straight. The first dorsal fin has a bluntly pointed apex with an origin above or posterior to the axils of the pectoral fins. The origin of the anal fin is slightly behind that of the second dorsal fin. The night shark (Carcharhinus signatus) is sometimes confused with the bignose shark, however there are characteristics that distinguish these two species © George Burgess Bignose sharks are similar to night sharks (C. signatus) in appearance, however night sharks have a second dorsal fin free rear tip that is at least twice as long as the second dorsal fin height while the bignose shark does not have a long second dorsal fin free rear tip. C. signatus also has green eyes. Bignose Shark © H.W. Pratt · Coloration Grayish body with no prominent markings other than being white below and having black tips inner corners of the pectoral fins. The tips of all fins other than the pelvics are dusky in color. There may be a green sheen along the gills of freshly collected specimens. Upper and lower teeth of the bignose shark source: FAO Species Catalogue, Vol. 4 Part 2 - Sharks of the World ·Dentition Teeth located in the upper jaw are large and broadly triangular with serrated edges except for the first two series at each side of symphysis which have concave lateral margins, straight to convex medial margins, and both margins are serrated. There is one or two small symphysial teeth. Lower teeth are narrow with finely serrated margins, narrow serrated cusps, and one symphysial tooth.There are 14-16 teeth on each side of the upper jaw (not counting the symphysial teeth) and 14 or 15 in the lower jaw. Bignose shark on top, dusky shark below © George Burgess ·Size, Age, and Growth Bignose sharks may reach lengths to 9.8 feet (3 m) TL and weights of 370 pounds (167.8 kg). At birth, bignose pups are between 2 to 3 feet (70 to 90 cm) in length. Males reach maturity at 7.1 feet (216-217 cm) in length and females at 7.4-9.3 feet (226-282 cm). Dogfish are preyed upon by the bignose shark courtesy VIMS · Food Habits Prey of this offshore shark consists of bony fishes including mackerels, soles, and batfish; and other elasmobranchs including dogfish, catsharks,and stingrays; and cephalopods. · Reproduction Reproductive mode is viviparous with yolksac placentas. Birth occurs during different times of the year depending upon location, in the Mediterranean this is from August to September while off Madagascar birth occurs during September and October. Litter size ranges from 3-11 pups approximately 2.3-3.0 feet (70-90 cm) in length. White sharks may prey upon immature bignose sharks © Klaus Jost · Predators Other sharks are potential predators on juvenile bignose sharks. Importance to Humans The bignose shark is caught by offshore trawlers and rarely by hook and line. It is harvested in the Caribbean region with deep longlines and is utilized for fish meal for animal feed, and for oil. In U.S. waters, this species is currently prohibited from capture in the commercial shark fishery. Danger to Humans Although this shark is large, it poses little threat to humans due to its deepwater habitat. Commercial shark fishing vessel © FLMNH Division of Ichthyology Conservation The bignose shark is listed as "Data Deficient" throughout its range with the exception of Australia where it is assessed as "Least Concern" by the World Conservation Union (IUCN). The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species. The "Data Deficient" assessment is indicative of the need for furhter information on fisheries and population status for this species. The longline bignose shark fishery is managed and regulated by the National Marine Fisheries Service off the coast of the U.S. At this time, bignose sharks are prohibited from harvest in U.S. waters. If this species is caught, it must be released immediately into the water in a manner that maximizes the shark's survival. Prepared by: Cathleen Bester