Broadnose Shark, Notorynchus cepedianus (Péron 1807)
A Broadnose Shark, Notorynchus cepedianus. Source: Ross Robertson / Shorefishes of the tropical eastern Pacific online information system. License: CC BY Attribution-Noncommercial-ShareAlike 3.0
A grey to greyish brown speckled and spotted shark with 7 pairs of gill slits, a broad rounded head with a short blunt snout and a singe dorsal fin, far back on the body.
Although quite sluggish, Broadnose Sharks are large, powerful predators, and can be aggressive, particularly if provoked. The species is responsible for a number of attacks on humans in public aquaria - there have been no verified attacks in open water.
Great footage of a female Broadnose Shark (aka Sevengill Sharks) at Millers Point, Cape Town, South Africa.
Broadnose Sharks (aka cow sharks) off Cape Town, South Africa.
Broadnose Shark, Notorynchus cepedianus (Péron 1807)
More Info
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Distribution |
Broken Bay (New South Wales) around southern Australia to Esperance (Western Australia). Elsewhere, the species occurs in most temperate seas worldwide; absent from the North Atlantic and Mediterranean Sea. The species occurs in temperate waters, usually in shallow, nearshore areas from the surface to 570 m, mostly <136 m, and often in surface waters. Large individuals often inhabit offshore waters, although they also occur near the bottom in the deeper areas of bays and harbours. Smaller individuals are more commonly found inshore. Broadnose Sharks are usually seen cruising over rocky reef habitats, as well as over sandy and muddy areas. |
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Features |
Body elongate, shallow (approx. 11% TL); no keels or precaudal pits on caudal peduncle. Head moderately large (approx. 17% TL), narrow; snout tapering, length more than 1.5 times internasal distance; nostrils not connected to mouth by groove; eyes oval; spiracles minute; teeth in upper jaw fang-like, with slender oblique cusp, those laterally with one or two smaller cusps on either side of base, teeth in lower jaw comb-like with six to ten cusps, second distinctly longer than others, distinctive median tooth in lower jaw only, rear teeth in both jaws rudimentary; seven gill slits in front of pectoral fin. Single dorsal fin near tail, above region between ventral and anal fins; anal fin small, height about half height of dorsal fin; caudal fin heterocercal, upper lobe long (approx. 30% TL), with distinct sub- terminal notch, lower lobe short. Pectoral fins moderately small, broad, tip narrowly rounded, hind margin weakly concave. |
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Size |
To about 3 m in length. |
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Feeding |
Opportunistic predators that use their sharp, jagged upper jaw teeth to grab and hold their prey. The large, wide saw-like teeth in the lower jaw are used for cutting and tearing flesh. The species reportedly feeds on a wide range of bony fishes, sharks, rays, seals, dolphins and carrion. |
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Biology |
Broadnose sharks are aplacental viviparous (ovoviviparous) - embryos develop from eggs that hatch in the uterus of the mother. They are nourished via the yolk-sac then absorb nutrients from uterine secretions until they are born. Broadnose sharks have large litters, and pups are born at a length of 40-45 cm. Males mature at 1.5 m, females at 2.2 m. |
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Fisheries |
Heavily fished throughout most of their range. In Australian waters, they are caught by commercial and recreational fishers, and the flesh is marketed as flake. |
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Remarks |
Broadnose sharks are unpredictable and can be aggressive if provoked. Although the species is responsible for a number of attacks on humans, none have been recorded in open waters. |
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Species Citation |
Squalus cepedianus Péron, F. 1807. Voyage de Découvertes aux Terres Australes, Fait par Ordre du Gouvernement, sur les Corvettes la Géographe, le Naturaliste et la Goulette le Casuarina, pendant les années 1800, 1801, 1802, 1803 et 1804. Paris : Arthus Bertrand Vol. 1: 337. Type locality: Adventure Bay, Tasmania. |
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Author |
Bray, D.J. 2023 |
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Resources |
Broadnose Shark, Notorynchus cepedianus (Péron 1807)
References
Abrantes, K.G. & Barnett, A. 2011. Intrapopulation variations in diet and habitat use in a marine apex predator, the broadnose sevengill shark Notorynchus cepedianus. Marine Ecology Progress Series 442: 133-148. https://doi.org/10.3354/meps09395
Bass, A.J., Hemstra, P.C. & Compagno, L.J.V. 1986. Hexanchidae. pp. 45-47 in Smith, M.M. & Heemstra, P.C. (eds.) Smiths' sea fishes. MacMillan, South Africa.
Compagno, L.J.V. 1984. FAO Species Catalogue. Sharks of the World. An annotated and illustrated catalogue of shark species known to date. Hexanchiformes to Lamniformes. FAO Fisheries Synopsis No. 125. Rome : FAO Vol. 4(1) pp. 1-249.
Compagno, L.J.V., Dando, M. & Fowler, S. 2005. A Field Guide to the Sharks of the World. London : Collins 368 pp.
Ebert, D.A. 1991. Observations on the predatory behaviour of the sevengill shark Notorynchus cepedianus. South African Journal of Marine Science 11(1): 455-465.
Finucci, B., Barnett, A., Cheok, J., Cotton, C.F., Kulka, D.W., Neat, F.C., Pacoureau, N., Rigby, C.L., Tanaka, S. & Walker, T.I. 2020. Notorynchus cepedianus. The IUCN Red List of Threatened Species 2020: e.T39324A2896914. https://dx.doi.org/10.2305/IUCN.UK.2020- 3.RLTS.T39324A2896914.en
Gomon, M.F., J.C.M. Glover & R.H. Kuiter (eds) 1994. The fishes of Australia's south coast. Flora and Fauna of South Australia Handbooks Committee. State Printer, Adelaide. 1-992.
Hammerschlag, N., Williams, L., Fallows, M. & Fallows, C. 2019. Disappearance of white sharks leads to the novel emergence of an allopatric apex predator, the sevengill shark. Scientific Reports 9(1908) https://doi.org/10.1038/s41598-018-37576-6
Hutchins, J.B. & Swainston, R. 1986. Sea Fishes of Southern Australia. Complete field guide for anglers and divers. Perth : Swainston Publishing 180 pp.
Kemp, N.R. 1978. Detailed comparisons of the dentitions of extant hexanchid sharks and tertiary hexanchid teeth from South Australia and Victoria, Australia (Selachii : Hexanchidae). Memoirs of the National Museum of Victoria 39: 61-83 figs 1-5 pls 12-15
Kuiter, R.H. 1993. Coastal Fishes of South-eastern Australia. Bathurst : Crawford House Press 437 pp.
Last, P.R. & Stevens, J.D. 2009. Sharks and Rays of Australia. Collingwood : CSIRO Publishing Australia 2, 550 pp.
Last, P.R., Scott, E.O.G. & Talbot, F.H. 1983. Fishes of Tasmania. Hobart : Tasmanian Fisheries Development Authority 563 pp. figs.
Macbeth, W.G., Vandenberg, M. & Graham, K.J. 2008. Identifying Sharks and Rays; a Guide for Commercial Fishers. Sydney : New South Wales Department of Primary Industry 71 pp.
May, J.L. & Maxwell, J.G.H. 1986. Field Guide to Trawl Fish from Temperate Waters of Australia. Hobart : CSIRO Division of Marine Research 492 pp.
Péron, F. 1807. Voyage de Découvertes aux Terres Australes, Fait par Ordre du Gouvernement, sur les Corvettes la Géographe, le Naturaliste et la Goulette le Casuarina, pendant les années 1800, 1801, 1802, 1803 et 1804. Paris : Arthus Bertrand Vol. 1 496 pp.
Schmidt-Roach, A.C.J. 2019. Stock structure and critical habitats for a key apex predator : the broadnose sevengill shark Notorynchus cepedianus. University Of Tasmania. PhD Thesis. https://doi.org/10.25959/100.00031726
Stehfest, K.M., Patterson, T.A., Barnett, A. & Semmens, J.M. 2014. Intraspecific differences in movement, dive behavior and vertical habitat preferences of a key marine apex predator. Marine Ecology Progress Series 495: 249-262.
Stewart, A.L. 2015. 21 Family Hexanchidae, pp. 115-118 in Roberts, C.D., Stewart, A.L. & Struthers, C.D. The Fishes of New Zealand. Wellington : Te Papa Press Vol. 2 pp. 1-576.
Waite, E.R. 1921. Illustrated catalogue of the fishes of South Australia. Records of the South Australian Museum (Adelaide) 2(1): 1-208 293 figs pl. 1 (as Notorhynchus pectorosus)
White, W. 2008. Shark Families Heterodontidae to Pristiophoridae. pp. 32-100 in Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.
Whitley, G.P. 1931. Studies in Ichthyology No. 5. Records of the Australian Museum 18(4): 138-160 figs 1-2 pls 20-21 (described as Notorynchus macdonaldi, type locality Manly, Sydney, NSW)
Whitley, G.P. 1934. Notes on some Australian sharks. Memoirs of the Queensland Museum 10(4): 180-200 figs 1-4 pls 27-29
Whitley, G.P. 1940. The Fishes of Australia. Part 1. The sharks, rays, devil-fish, and other primitive fishes of Australia and New Zealand. Sydney : Roy. Zool. Soc. N.S.W. 280 pp. 303 figs.
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