|Scientific Name:||Heterodontus portusjacksoni|
|Species Authority:||(Meyer, 1793)|
Squalus portusjacksoni Meyer, 1793
|Red List Category & Criteria:||Least Concern ver 3.1|
|Reviewer(s):||Musick, J.A. & Fowler, S.L. (Shark Red List Authority)|
This assessment is based on the information published in the 2005 shark status survey (Fowler et al. 2005).
This abundant shark is endemic to Australian waters. There is currently no evidence to suggest that Port Jackson Shark (Heterodontus portusjacksoni) populations face any risk of extinction. Although caught in commercial fisheries in substantial quantities most are returned to the water alive. Habitat modification and other environmental factors do not appear to be a threat to the health of populations.
|Range Description:||The Port Jackson Shark is a common inhabitant of the Australian continental shelf south of 20°S. It has been recorded from estuarine areas, to depths of 245m (Last and Stevens 1994).|
Native:Australia (New South Wales, South Australia, Western Australia)
|FAO Marine Fishing Areas:||
Indian Ocean – eastern; Pacific – southwest; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Habitat and Ecology:||
Port Jackson Sharks feed mostly on benthic invertebrates, especially sea urchins (Last and Stevens 1994). Other reported prey include sea stars, polychaete worms, gastropods, prawns, crabs and small fish (Compagno 1984a).
The Port Jackson shark is oviparous, with mature females producing 10-16 eggs each year. The eggs are deposited in fissures and caves of shallow rocky reefs. Juveniles hatch at a size of 23 cm from the eggs after 12 months. Males mature at an age of 8-10 years at a size of 75 cm, while females mature at 11-14 years and 80-95 cm. These ages at maturity are based on captive animals and the age and growth of the wild population needs to be examined to confirm these estimates. Males grow to a maximum size of 105 cm; females grow to at least 123 cm (McGaughlin and O'Gower 1971, Last and Stevens 1994).
Port Jackson sharks are abundant inhabitants of coastal reefs throughout their ranges (Last and Stevens 1994). They are most active at night when they are feeding. McGaughlin and O'Gower (1971) gave a detailed description of the habitat use and movements of Port Jackson sharks in the waters off New South Wales. Males and females move into inshore reef areas in July. Mating occurs in July and August and eggs are laid in August and September. At the end of the breeding season males move into deeper water, followed by females at the end of their egg laying period. Some adults remain offshore over summer, while others migrate. Animals have been recorded up to 850 km from the reproductive areas. Females appear to migrate further than males. Juveniles hatch in the nearshore reef areas and normally remain there until they near maturity.
McGaughlin and O'Gower (1971) estimated that the growth rates of captive animals were 5-6 cm for juveniles and 2-4 cm for adults.
|Use and Trade:||Small individuals are captured for use in the hobbyist aquarium trade and fetch good prices. Live animals are sold both domestically and internationally. Port Jackson Sharks advertised by aquarium suppliers in the US sell for up to US$180. Specimens are also collected by commercial aquaria for display purposes, but in relatively small numbers. Large commercial aquariums are able to successfully breed Port Jackson Sharks in captivity, reducing the reliance on wild caught animals.|
Port Jackson Sharks are commonly caught in demersal gillnet fisheries operating in southern Australia. At times they may account for the majority of the catch (in numbers). Catch figures, however, are unavailable as fishermen do not land this species. Their flesh and fins are considered of poor quality and they are not used commercially. Most are discarded, often alive. Some fishers consider them to be a pest and kill them before discarding them. Observations on catches of demersal gillnet fishers in southern Western Australia have indicated that stocks remain relatively healthy, with large catches regularly made after 20 years of intensive fishing (Simpfendorfer unpubl.).
Small individuals are captured for use in the hobbyist aquarium trade and fetch good prices. Live animals are sold both domestically and internationally. Port Jackson Sharks advertised by aquarium suppliers in the US sell for up to US$180. Specimens are also collected by commercial aquaria for display purposes, but in relatively small numbers. Large commercial aquariums are able to successfully breed Port Jackson Sharks in captivity, reducing the reliance on wild caught animals.
Recreational fishers occasionally catch Port Jackson Sharks, but they are not specifically targeted because of their low flesh quality. A survey of recreational boat anglers on the lower west coast of Western Australia estimated that the recreational catch by this sector of the recreational fishery was 273 individuals in the period from September 1996 to August 1997 (N. Sumner pers. comm.). These levels of catch are very minor when compared to commercial catches.
|Conservation Actions:||The only specific management regulation that exists for Port Jackson Sharks is the recreational trip limit for sharks imposed by Western Australia (four of any species). No other States have bag or size limits that cover Port Jackson Sharks. Commercial collectors of live specimens for the aquarium trade are normally licensed by State Governmental legislation.|
Compagno, L.J.V. 1984. Sharks of the World. An annotated and illustrated catalogue of shark species to date. Part I (Hexanchiformes to Lamniformes). FAO Fisheries Synopsis, FAO, Rome.
Fowler, S.L., Cavanagh, R.D., Camhi, M., Burgess, G.H., Cailliet, G.M., Fordham, S.V., Simpfendorfer, C.A. and Musick, J.A. (comps and eds). 2005. Sharks, Rays and Chimaeras: The Status of the Chondrichthyan Fishes. Status Survey. pp. x + 461. IUCN/SSC Shark Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK.
Last, P.R. and Stevens, J.D. 1994. Sharks and Rays of Australia. CSIRO, Melbourne, Australia.
McLaughin, R.H. and O?Gower, A.K. 1971. Life history and underwater studies of a heterodont shark. Ecological Monographs 41(4): 271?289.
|Citation:||Simpfendorfer, C. 2005. Heterodontus portusjacksoni. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 02 September 2014.|