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Orectolobus ornatus
– Near Threatened
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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CHONDRICHTHYES
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Order:
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ORECTOLOBIFORMES
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Family:
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ORECTOLOBIDAE
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Scientific Name:
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Orectolobus ornatus
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Species Authority:
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(de Vis, 1883)
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Synonym/s:
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Orectolobus devisi Ogilby, 1916 Orectolobus ornatus ssp. halei Whitley, 1940
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Common Name/s:
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| English | — | BANDED WOBBEGONG, CARPET SHARK, GULF WOBBEGONG, ORNATE WOBBEGONG |
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Assessment Information
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Red List Category & Criteria:
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NT ver 3.1 (2001)
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Year Assessed:
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2003
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Assessor/s:
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Pollard, D., Gordon, I., Flaherty, A. & Pogonoski, J. (SSG Australia & Oceania Regional Workshop, March 2003)
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Evaluator/s:
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Shark Specialist Group Australia & Oceania Regional Group (Shark Red List Authority)
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Justification:
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Probably an Australian endemic (other locality records unconfirmed, pending taxonomic review). A biologically vulnerable low-fecundity species, apparently territorial (site-attached) within its shallow bathymetric range. Caught in commercial and recreational fisheries, as a target species and as bycatch. Historic catch data are aggregated with Orectolobus maculatus, but serious declines (more than 60% between 1990 and 2000) for these two species combined are documented for the east coast (NSW), where the population has been assessed as Vulnerable, and where there is still no management plan implemented. Catch levels appear to be low and stable in southern and western Australia, however, given the declines on the east coast due to its vulnerability to exploitation, this species is assessed as Near Threatened throughout the rest of its range. More information is needed on population structure, life history and ecology in order to develop management policies and re-assess conservation status.
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Geographic Range
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Range Description:
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Regional endemic (probable): tropical eastern Australia, southwards to Flinders Island in Bass Strait (Last and Stevens 1994) and west and north-westwards to Shark Bay in Western Australia (Hutchins 1990). It should be noted that the NSW population (from Port Stephens northwards) appear to be two species, differentiated at least by significant differences in size at maturity (C. Huveneers, unpublished data).
Global: Unconfirmed records from Indonesia, Papua New Guinea (PNG) and Japan.
Because of taxonomic difficulties with this genus in the previously presumed northern part of its range, this species should currently be treated as an Australian endemic (L.J.V. Compagno, pers. comm).
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Countries:
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Native:
Australia (South Australia, Tasmania, Victoria, Western Australia)
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FAO Marine Fishing Areas:
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Native:
Indian Ocean-eastern; Pacific-southwest; Pacific-western central
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Population
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Population Trend:
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Habitat and Ecology
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Habitat and Ecology:
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A common inshore bottom-dwelling shark of continental shelves, found on algal-covered rocky reef areas and coral reefs (Compagno 1984a), occurring to at least 117 m depth (Last and Stevens 1994, Pogonoski et al. 2002) and is also known from around offshore islands. Orectolobus ornatus occurs as solitary individuals or in aggregations. This nocturnal shark rests on the bottom during the day in caves, under ledges on reefs, and in trenches (Compagno 2001). Maximum size is approximately 288 cm total length (TL). Size at birth is around 21 cm TL. Size at maturity is about 180 cm TL but others mature at 63 cm TL (suggesting the possibility of more than one species being included under this taxon). The species' reproductive mode is aplacental viviparity with 12 to 20 pups/litter, although individuals maturing at the smaller size have been shown to have 7 to 16 pups/litter.
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System:
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Marine
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List of Habitats:
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| 9.1 | Marine Neritic - Pelagic |
| 9.8 | Marine Neritic - Coral Reef |
| 10.1 | Marine Oceanic - Epipelagic (0-200m) |
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Threats
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Threats:
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Wobbegong sharks are commonly caught in trawls, beach seines, gillnets, lobster pots and traps, by hook-and-line, and very occasionally by spearfishing. The flesh is now highly regarded as food, although in the past was generally of only limited commercial value. The attractive skin has previously been used as a decorative leather (Last and Stevens 1994) although wobbegongs are currently not targeted for their skin. These sharks are taken as bycatch (often retained) by commercial fisheries throughout their range (Pogonoski et al. 2002). There appear to be relatively low and apparently stable catch levels in southern and western coastal fisheries, and low levels of utilization in Western Australia. However, serious declines have been observed in NSW, demonstrating the vulnerability of this species to exploitation. Generally, declines of up to two thirds have been observed in NSW fisheries aggregated catches of wobbegong sharks (consisting of O. maculatus and O. ornatus) between 1990 and 2000. It should be noted that the effort data are more difficult to interpret, and it has been suggested that the number of fishers targeting wobbegongs may have declined (C. Huveneers, pers.comm). Assessment and management is complicated by the aggregation of the catch data (NSW Fisheries 2001). Based on the future possibility of segregated data for O. ornatus and O. maculatus becoming available in some regions due to improved fisheries data collection, and clarification of the taxonomy of these species, future separate national assessments would be warranted.
Commercial fishing by a variety of methods is potentially threatening wobbegong species in southern Australian waters. Wobbegongs are taken in the GABTF, SETF, SSF and the South East Non-Trawl Fishery (AFMA logbook data, unpublished, cited by Pogonoski et al. 2002). Most of the above fisheries take these species as bycatch and they are often utilized. This species is also taken in nets in the Western Australian Shark Fishery (WASF) and on hook in the New South Wales Drop-line Fishery (NSWDF), and is sometimes marketed (Daley et al. 2002). Wobbegongs, mostly less than 2 m long, are part of the bycatch in Western Australia temperate shark fisheries, but are discarded because there is no market for them (Simpfendorfer 1999).
Recreational fishers in NSW do not tend to target this species (C. Huveneers, pers.comm.). Some spearfishers catch a small number of wobbegongs but this practice is limited as they do not pose a challenge (Morrow, unpublished data). In Western Australia, a Fisheries Department survey conducted in 1996–1997 between Augusta and Kalbarri, reported that up to 1,000 wobbegongs were caught and kept by recreational fishers during that period (Sumner and Williamson 1999). Wobbegongs are also known to be taken by recreational fishers in South Australia, with no bag or size limits in these states. There is evidence of site-attachment for wobbegongs, making them particularly susceptible to fishing pressure, although further work is necessary in this area (Pogonoski et al. 2002). This species may also be susceptible to impacts on inshore coastal habitat, particularly juveniles which often utilize such areas.
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List of Threats:
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| 3.1.1 | Harvesting (hunting/gathering) - Food - Subsistence use/local trade (ongoing) |
| 3.1.2 | Harvesting (hunting/gathering) - Food - Sub-national/national trade (ongoing) |
| 3.4.1 | Harvesting (hunting/gathering) - Materials - Subsistence use/local trade (ongoing) |
| 3.4.2 | Harvesting (hunting/gathering) - Materials - Sub-national/national trade (ongoing) |
| 3.5.1 | Harvesting (hunting/gathering) - Cultural/scientific/leisure activities - Subsistence use/local trade (ongoing) |
| 4.1.1.1 | Accidental mortality - Bycatch - Fisheries-related - Hooking (ongoing) |
| 4.1.1.2 | Accidental mortality - Bycatch - Fisheries-related - Netting (ongoing) |
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Conservation Actions
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Conservation Actions:
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A discussion paper in relation to the management of wobbegong sharks has been prepared for NSW waters (NSW Fisheries 2001), but no management plan is yet in place. There appear to be no other species-specific management arrangements in other Australian states. Some protection may be offered by those protected areas already being implemented for Grey Nurse Sharks Carcharias taurus in NSW. These species also occur in some Marine Protected Areas (MPAs) in NSW: Julian Rocks Aquatic Reserve and Solitary Islands Marine Park, and possibly in Shark Bay Marine Park, Western Australia and Hamelin Pool Marine Nature Reserve, WA. The species also occurs in some MPAs in Queensland. Recently, an in-possession limit of two wobbegong sharks per person was introduced for recreational fishers in NSW (Pogonoski et al. 2002).
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List of Conservation Actions:
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| 1.1.1 | Policy-based actions - Management plans - Development (needed) |
| 1.1.2 | Policy-based actions - Management plans - Implementation (needed) |
| 1.2.1.2 | Policy-based actions - Legislation - Development - National level (in place) |
| 3.1 | Research actions - Taxonomy (needed) |
| 3.2 | Research actions - Population numbers and range (needed) |
| 3.3 | Research actions - Biology and Ecology (needed) |
| 3.4 | Research actions - Habitat status (needed) |
| 3.9 | Research actions - Trends/Monitoring (needed) |
| 4.4 | Habitat and site-based actions - Protected areas (in place, needed) |
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Bibliography
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Bibliography:
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Compagno, L.J.V. 2001. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Vol. 2. Bullhead, mackeral and carpet sharks (Heterodontiformes, Lamniformes and Orectolobiformes). FAO species catalogue for fisheries purposes. No. 1. Vol. 2. FAO, Rome. Last, P.R. and Stevens, J.D. 1994. Sharks and Rays of Australia. CSIRO, Australia. NSW Fisheries 2001. Discussion paper on Management of Wobbegong Sharks in New South Wales. Pogonoski, J.J., Pollard, D.A. and Paxton, J.R. 2002. Conservation Overview and Action Plan for Australian Threatened and Potentially Threatened Marine and Estuarine Fishes. Environment Australia, Canberra, Australia. (See http://www.deh.gov.au/coasts/publications/marine-fish-action/index.html). Shark Specialist Group. For more information, see the Specialist Group website.
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