| Common names: shark (English), tiburón (Espanol) |
Carcharhinus brachyurus (Günther, 1870)
Narrowtooth shark, Copper shark, Bronze whaler shark
Body slender; snout blunt, broad, rounded, its length 1.1-1.4 times the distance between nostrils; nasal orifices small and well separated; round eye; spiracle absent; upper front teeth narrow and hooked, with finely serrated points; lower front teeth narrow, high, straight; 5 short gill slits, last 2 over pectoral fin base; first dorsal moderately high (6.8-9.7% of TL), front edge straight, origin over or just behind rear edge of pectoral; second dorsal moderately high origin over anal origin; pectoral long, straight; usually no raised crest on back between dorsal fins; tail strongly asymmetrical, with well developed lower lobe, undulating ridge along dorsal surface of top lobe, and a ventral notch near tip of that lobe; notch on top of tail base.
Dark grey-brown above, belly whitish; a pale stripe along flank; tips of pelvics and tips and rear borders of pectorals dark to blackish.
Size: 325 cm.
Habitat: inshore to offshore, continental, from surfline deeper.
Depth: 0-360 m.
Circumglobal; California to the Gulf of California and central Mexico, the Revillagigedos, Peru.
Global Endemism: All species, TEP non-endemic, Circumtropical ( Indian + Pacific + Atlantic Oceans), "Transpacific" (East + Central &/or West Pacific), West + East Pacific (but not Central), East Pacific + Atlantic (East +/or West), East Pacific + East (not West) Atlantic
Regional Endemism: All species, Eastern Pacific non-endemic, Tropical Eastern Pacific (TEP) non-endemic, Temperate Eastern Pacific, primarily, California + Peruvian provinces, primarily, Continent + Island (s), Continent, Island (s)
Climate Zone: North Temperate (Californian Province &/or Northern Gulf of California), Northern Subtropical (Cortez Province + Sinaloan Gap), Northern Tropical (Mexican Province to Nicaragua + Revillagigedos), South Temperate (Peruvian Province ), Antitropical (North and South temperate)
C. brachyurus is widespread in the Mediterranean but only sporadically reported possibly due to misidentification and lower abundance relative to other large sharks (Fergusson and Compagno 1995). C. brachyurus was the least abundant of the five pelagic sharks sampled in the northeast Atlantic and western Mediterranean by Muñoz-Chápuli (1984). The relationship between the Mediterranean and northeast Atlantic populations is unknown but it seems likely that pregnant females migrate from the Atlantic to breeding grounds off Morocco (Muñoz-Chápuli 1984). Stock structure in the Mediterranean is unknown. Despite being listed as common in US Atlantic shark landings by Rose (1996, pg. 26) C. brachyurus is absent from the western North Atlantic (Garrick 1982, Compagno 1984, Russell 1993, Castillo-Génez et al. 1998, J. Castro, pers. comm., L. Natanson, pers. comm., M. Grace, pers. comm.). In the southwest Atlantic C. brachyurus is relatively common off northern Argentina during summer, and is the most abundant species of Carcharhinus in Agentina (Chiaramonte 1998a, b). It is also common off Namibia and the west coast of South Africa (Compagno et al. 1989). In the Indian Ocean it is common off Eastern Cape, South Africa ranging north to Richard's Bay, Natal although it is rare north of Durban (Compagno et al. 1989, Cliff and Dudley 1992).
Range and population size is poorly known in the eastern Pacific. Although Compagno (1984) speculated that it may occur in Chile there are no documented records or specimens of C. brachyurus in Museum collections there (I. Kong, pers. comm). Philippi (1887) described two species, Hypoprion isodus and H. heterodus from Chile on the basis of two dried jaws (Garrick 1982). Garrick (1982) considered both to be species dubia placing them in Carcharhinus. The upper teeth in both jaws are too broad and the tooth counts are too low for either to be brachyurus (Garrick 1982). Garrick (1982) considered H. heterodus was likely to be C. obscurus or galapagensis. Pequeño (1989) also considered it likely H. heterodus corresponds to C. obscurus (I. Kong, pers. comm). Despite the lack of records and specimens it seems likely that C. brachyurus at least occasionally reaches northern Chilean waters from Peru. Little is known of its occurrence in Peru other than the juvenile specimens reported by Garrick (1982). C. brachyurus appears to be uncommon or rare in Mexico (Gulf of California and Baja California) but confusion with other Carcharhinus species could be a problem (O. Sosa, pers. com., L. Castillo, pers. comm.). Although very small juveniles have been collected from a number of locations in southern California suggesting it may breed there, C. brachyurus is considered to be a rare visitor to the west coast of the US (Garrick 1982, R. Lea, pers. comm., D. Ebert, pers. comm., G. Cailliet, pers. comm.). There are no records of C. brachyurus north of Point Conception (R. Lea, pers. comm), although based on what is known of its ecology in the Southern Hemisphere it could be expected to be common as far north as Monterey Bay (D. Ebert, pers. comm). This apparent rarity does not appear to be due to confusion with other species of Carcharhinus as the genus itself is rare in California (R. Lea, pers. comm). It is worth noting here that although Garrick (1982) synonymised C. lamiella with brachyurus the characters referred to in the description of lamiella were those diagnostic of C. obscurus. Consequently most records of lamiella from California are not referable to C. brachyurus (Garrick 1982). The populations in the northeast and southeast Pacific appear to be disjunct (Compagno 1984).
In Australian waters C. brachyurus is infrequently recorded north of Sydney or Perth, being most abundant between Albany (Western Australia) and Bass Strait (Last and Stevens 1994, R. McAuley, pers. comm., C. Simpfendorfer, pers. comm., J. Stevens, pers. comm.). It is the commonest Carcharhinus species in South Australia and Victoria (Cappo 1992). C. brachyurus has not been recorded from Lord Howe and Norfolk Islands (Last and Stevens 1994). In New Zealand waters C. brachyurus is common around the northern half of North Island, including Three Kings Islands, Middlesex Bank and Three Kings Rise, ranging south to Cook Strait in summer (Illingworth 1961, Garrick 1982, Francis 2001). Pregnant females and pups have been recorded as far south as Waimea Inlet, Nelson (about 41°S, C.D. unpublished data). C. brachyurus has not been recorded from the Kermadec Islands or the islands of the tropical southwest Pacific (Garrick 1982, Compagno 1984, Last and Stevens 1994, Cox and Francis 1997).
- Compagno, L.J.V. 1984 FAO Species Catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 2 - Carcharhiniformes. FAO Fish. Synop. 125(4/2):251-655. Rome: FAO. (Ref. 244)
- IGFA 2001 Database of IGFA angling records until 2001. IGFA, Fort Lauderdale, USA. (Ref. 40637)
- Randall, J.E., G.R. Allen and R.C. Steene 1990 Fishes of the Great Barrier Reef and Coral Sea. University of Hawaii Press, Honolulu, Hawaii. 506 p. (Ref. 2334)
- Walter, J.P. and D.A. Ebert 1991 Preliminary estimates of age of the bronze whaler Carcharinus brachyurus (Chondrichthyes: Carcharinidae) from southern Africa, with a review of some life history parameters. S. Afr. J. Mar. Sci. 10:37-44. (Ref. 3209)
- Froese, R. & D. Pauly (Editors). (2014). FishBase. World Wide Web electronic publication.
Catalog Number: USNM 114946
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Fishes
Year Collected: 1938
Locality: New South Wales, Off Sydney, New South Wales, Australia, Pacific
- Syntype: Stead, D. G. 1938. The Australian Naturalist. 10 (3): 102.
Catalog Number: USNM 27366
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Fishes
Collector(s): D. Jordan
Year Collected: 1880
Locality: San Diego, California, San Diego County, California, United States, Pacific
- Type: Jordan, D. S. & Gilbert, C. H. 1882. Proceedings of the United States National Museum. 5 (269): 110.
Inshore/Offshore: Offshore, In & Offshore, Inshore
Water Column Position: Surface, Near Surface, Mid Water, Near Bottom, Water column only
Habitat: Water column
FishBase Habitat: Pelagic
Habitat and Ecology
Juvenile and adult C. brachyurus segregate by size and sex (Muñoz-Chápuli 1984, Smale 1991, Cliff and Dudley 1992, Chiaramonte 1998). Juveniles occur in shallow water (less than 30 m depth) year round, whereas adults are most abundant inshore during spring and summer. Adults and sub-adults are found over the shelf and around offshore islands and banks throughout the year. The movement of adult females inshore in spring is related to breeding. Nursery areas tend to be large and ill defined but include shallow banks, large shallow bays, inlets and harbours as well as the open coast (Muñoz-Chápuli 1984, Smale 1991, Cappo 1992, Chiaramonte 1998b, Fergusson and Compagno 1995). These areas also tend to be nurseries for other common coastal sharks such as Smoothhound (Mustelus spp.), School Shark (Galeorhinus galeus) and Smooth Hammerhead (Sphyrna zygaena). In New Zealand pregnant females and neonates have been reported as far south as Waimea Inlet (41°20'S) on the west coast and Hawke Bay (40°S) on the east coast (Garrick 1982, C.D. unpublished data). In Australia neonates and small juveniles (less than 1 m total length) have been reported from Albany (Western Australia), Port Lincoln, the upper Gulf St. Vincent and Robe (South Australia), and Port Phillip Bay (Victoria) (Cappo 1992, R. McAuley pers. comm., T. Walker pers. comm., I.G. pers. obs). In South Africa the waters of the Eastern Cape are considered to be the main nursery area for this species (Smale 1991, Cliff and Dudley 1992). Elsewhere neonates and small juveniles have been recorded from: Rhodes, Nice and the banks off Al Hoceima (West Alboran Basin) in the Mediterranean (Garrick 1982, Muñoz-Chápuli 1984, Fergusson and Compagno 1995); Rio de Oro, Pulpito Bay, northwest Africa (Garrick 1982); Rio de Janeiro, Brazil (Garrick 1982); Bahia Blanca and Bahia San Blas, Distrito Bonaerense, Argentina (Chiaramonte 1998b); Paita and Guanape Cove, Peru (Garrick 1982); Bahia Sebastian Vizcaino, Baja California (Garrick 1982); San Diego Bay and Oceanside, California (Garrick 1982); near Niigata, Sea of Japan (Garrick 1982).
Segregation also occurs along latitudinal gradients (Muñoz-Chápuli 1984, Smale 1991, Cliff and Dudley 1992). Adult males are present in subtropical regions throughout the year, whereas females and immature C. brachyurus migrate into these regions during winter. Most adult females return to temperate regions to breed in the spring. The males also appear to migrate to higher latitudes in late winter-spring presumably to mate (Cliff and Dudley 1992). Mating probably occurs offshore as the females disperse from the nursery areas. Post-partum females bearing unhealed mating scars have been caught over the shelf (about 100 m depth) in early February off Hawke Bay, New Zealand (C.D. pers. obs). C. brachyurus inhabiting temperate areas also range into higher latitudes during the summer (Ayling and Cox 1982, Compagno 1984, Compagno et al. 1989, Cappo 1992, Last and Stevens 1994, Chiaramonte 1998b). These latitudinal movements may be in response to changes in water temperature or prey migrations (Compagno 1984, Comapgno et al. 1989, Cliff and Dudley 1992, Chiaramonte 1998b). In South Africa female C. brachyurus appear to follow the sardine run from the Eastern Cape to Natal during winter (Compagno et al. 1989, Cliff and Dudley 1992). The mean distance travelled by tagged C. brachyurus in South Africa is 163 km during 162 days at liberty, the maximum distance travelled was 1,320 km (Cliff and Dudley 1992). In South Australia tagged adults have been resighted at their tagging location after a year at liberty suggesting this species, like other Carcharhinids, is philopatric (I.G. pers. obs). Movement between New Zealand and Australia, or other regional populations has not been documented.
C. brachyurus occur singly and in loose schools sometimes numbering hundreds of individuals (Smale 1991, Cappo 1992, Cliff and Dudley 1992, C.D. unpublished data). In New Zealand and Australia these aggregations are most conspicuous in shallow water near shore during spring and summer, and in South Africa during the winter sardine run. Divers and sport fishers also report aggregations of C. brachyurus around offshore islands and banks off northern New Zealand during winter. Aggregations of large sharks reported in the surf zone near the entrances to harbours in northern New Zealand during spring may be related to breeding however at other times schooling may be a response to a local abundance of prey (Compagno et al. 1989, Cappo 1992).
Reproductive periodicity is probably biennial like most other large Carcharhinids (Castro et al. 1999). In the Southern Hemisphere parturition probably occurs from June to January, with a peak in October and November (Smale 1991, Cliff and Dudley 1992, Chiaramonte 1998b). Reproduction is viviparous, with a yolk sac placenta. Litters range from 7 to 24, with an average of 15 reported from South Africa (Garrick 1982, Smale 199, Cliff and Dudley 1992, Chiaramonte 1998b). Size at birth is about 60 cm total length (range 55-67 cm total length) (Garrick 1982, Smale 1991, Cliff and Dudley 1992). Cliff and Dudley (1992) estimated gestation lasts about 12 months. However their data show two embryonic size classes are present in the January and June-July samples, and a better description of embryonic growth is obtained if a 15 to 21 month gestation period is assumed (r² = 0.798 cf. 0.628). Males mature between 206 and 235 cm total length, and females from 227 to 244 cm total length. Age at maturity in South Africa is estimated to be 13 to 19 years for males, and 19-20 years for females (Walter and Ebert 1991). Maximum size of C. brachyurus is at least 295 cm total length and it is reported to reach 350 cm total length (Ayling and Cox 1982, Compagno 1984, Last and Stevens 1994). Maximum age is unknown. Productivity is estimated to be low to very low, with a minimum population doubling time of more than 14 yrs (K=0.04) (Froese and Pauly 2002, Fish Base).
- Bogutskaya, N.G. 2007 Preliminary assignment of coordinates to type localities in the Catalog of Fishes. Unpublished dbf file. (Ref. 58018)
- Riede, K. 2004 Global register of migratory species - from global to regional scales. Final Report of the R&D-Projekt 808 05 081. Federal Agency for Nature Conservation, Bonn, Germany. 329 p. (Ref. 51243)
Water temperature and chemistry ranges based on 15 samples.
Depth range (m): 23 - 536
Temperature range (°C): 6.409 - 20.525
Nitrate (umol/L): 0.276 - 21.897
Salinity (PPS): 34.440 - 35.993
Oxygen (ml/l): 4.364 - 5.304
Phosphate (umol/l): 0.134 - 1.821
Silicate (umol/l): 1.128 - 18.665
Depth range (m): 23 - 536
Temperature range (°C): 6.409 - 20.525
Nitrate (umol/L): 0.276 - 21.897
Salinity (PPS): 34.440 - 35.993
Oxygen (ml/l): 4.364 - 5.304
Phosphate (umol/l): 0.134 - 1.821
Silicate (umol/l): 1.128 - 18.665
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.
Recorded at 100 meters.
Habitat: pelagic. Copper shark. Gunther, 1870 Attains 2.9 Metres. Litter of 13 - 20 pups. Has been blamed for several attacks on man. Common from Namibia to Port Elizabeth.
Diet: octopus/squid/cuttlefish, bony fishes
Life History and Behavior
Lifespan, longevity, and ageing
Molecular Biology and Genetics
Barcode data: Carcharhinus brachyurus
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Carcharhinus brachyurus
Public Records: 9
Specimens with Barcodes: 25
Species With Barcodes: 1
CITES: Not listed
IUCN Red List Assessment
Red List Category
Red List Criteria
- Needs updating
Catches appear to be stable in Australia. In New Zealand, although there may have been some reduction in population size due to fishing, C. brachyurus is apparently still common throughout its range. Management of this species in New Zealand, Australia and South Africa is simplified by having most, if not all of the population resident within each nation's EEZ, and the species is assessed as Least Concern in these regions. However, it is assessed as Data Deficient in the East Pacific, where there is no information and it appears to be uncommon or rare.
Throughout its range, it is known to be exploited by fisheries, but landings are grouped together with other Carcharhinus species, meaning any population declines are likely to go unnoticed, and its coastal nursery areas are potentially vulnerable to development and pollution. This, together with life history characteristics that make it especially vulnerable to overfishing has led to the global assessment of C. brachyurus as Near Threatened. The situation must be monitored as this species could soon qualify for a threatened category, on the basis of population declines due to fisheries exploitation, in other areas.
C. brachyurus is fished commercially in New Zealand (Francis 1998, Bagley et al. 2000, Ministry of Fisheries catch effort data), Australia (Cappo 1992), South Africa (Compagno et al.1989), Brazil (Amorim et al. 1998), Uruguay (Marín et al. 1998), Argentina (Chiaramonte 1998a, b), Mexico (Appelgate et al. 1993) and China (Parry-Jones 1996). C. brachyurus was not reported in trade from any of its Mediterranean range states by Rose (1996) but it is taken in net fisheries here and is usually lumped with other Carcharhinids (e.g., C. plumbeus) when landed (Fergusson and Compagno 1995). Little data is available for these fisheries. In Western Australia the "bronze whaler fishery" actually targets juvenile dusky shark (C. obscurus) (Heald 1987, Simpfendorfer 2001). C. brachyurus only constitutes about 3% of total reported landings in this fishery (R. McAuley pers. comm.). Carcharhinus spp. are also taken as bycatch in the Southern Shark Fishery (Victoria, Tasmania, South Australia). Between 1996-2001 mean annual landed catch of Carcharhinus spp. in this fishery was 71.5 tonnes (range 44-106 tonnes) (T. Walker pers. comm). The bulk of this (97-100%) was landed in South Australia, where landings increased from less than 20 tonnes a year in the early 1980s to 60-70 tonnes a year between 1988 and 1990 (Stevens in Castro et al. 1999). During the 1990s the landed catch has remained stable at around 70 tonnes a year, although a maximum of 105 tonnes was landed in 1999 (T. Walker pers. com.). The species composition of the bronze whaler catch in South Australia is unknown but is likely to be predominately C. brachyurus (Cappo 1992). In New Zealand reported commercial landings increased from 10 tonnes in 1989/90 to about 48 tonnes in 1995/96. Since then landings have declined steadily to about 20 tonnes in the 2001/02 fishing year (Ministry of Fisheries catch effort data). Most of the catch is taken by set net in the Hauraki Gulf and Firth of Thames. Reported landings from this area have been declining since 1992/93. No CPUE analysis of this fishery has been performed so it is uncertain if the decline in landings represents a decline in abundance or a change in fishing practice.
Although no fishery data is available for C. brachyurus in East Asia (i.e., Sea of Japan, Yellow Sea, East China Sea) directed shark fisheries have operated in the region since at least the 1950s, and sharks are a component of multi-species fisheries for more highly valued species such as tuna and swordfish (Parry-Jones and others in Phipps 1996). All directed fisheries for large coastal sharks in this region appear to have ceased during the 1970s due to declining catches and a shift in effort into offshore fisheries for tuna and salmon (Parry-Jones, and Kiyono in Phipps 1996). Parry-Jones (1996) observed that shark landings from coastal fisheries in China consisted mainly of small immature sharks (i.e., 90% <100 cm total length and 1 kg weight). The only C. brachyurus observed in markets during that survey was a juvenile weighing 5.5 kg in Fujian Province. Fishers from Fujian Province reported that large sharks were relatively common during the 1960s but are seldom caught now (Parry-Jones 1996). Fishing vessels from China, Taiwan, Hong Kong, Japan, South Korea, the Philippines and Viet Nam all operate in the South China Sea, East China Sea and Yellow Sea (Parry-Jones 1996). C. brachyurus is not reported to be an important component of Taiwan's shark fishery, either within Taiwanese waters, its distant-water shark fishing areas in Papua New Guinea, Indonesia and Mozambique, or its tuna longline and trawler fleets. The latter fishes waters of the South China Sea, Yellow Sea, East China Sea, India and northwest Africa (Chen et al. 2002).
In Argentina the main commercial fishery is located at Necochea. Reported annual landings range from 0 to 336 sharks (Chiaramonte 1998a). Chiaramonte (1998a) reported only two vessels targeted C. brachyurus, and observed that catches indicated this species was not sufficiently abundant to support a directed fishery should the school shark (G. galeus) stock collapse. In Chile directed shark fisheries are confined to the northern part of the country where artisanal fishers target shortfin mako (Isurus oxyrinchus) and blue shark (Prionace glauca) and may occasionally take Carcharhinus spp. (I. Kong pers. com.). Little information is available on the elasmobranch fisheries in Peru other than landings are dominated by smoothhounds (Mustelus spp) and batoids (Bonfil 1994). In 1990/91 landings crashed from over 25,000 tonnes to about 5,000 tonnes p.a. The reason for this crash is unknown and may not reflect a collapse of the fishery (Bonfil 1994). Mexican shark fisheries are the largest in America and the Pacific coast contributes about 60% of total landings (Bonfil 1994). There is also a significant bycatch of elasmobranchs in large scale trawl fisheries in the Mexican Pacific (Bonfil 1994). The Gulf of California represents one of the major fishing grounds in the Pacific and supports directed fisheries for Carcharhinus spp. (C. altimus, C. brachyurus, C. falciformis, C. leucus, C. limbatus, C. obscurus, C. porosus) (Appelgate et al. 1993, Bonfil 1994). Although information on stock size and species specific fishing mortality was limited or non-existent Bonfil (1994) considered it likely, given the level of exploitation that many shark stocks in the Gulf of California were close to their maximum sustainable yield or overfished. Neither Applegate et al. (1993) or Bonfil (1994) listed C. brachyurus as being heavily fished. However, as it is vulnerable to the same types of gear and may be naturally less abundant than those Carcharhinus spp. that dominate the landings, the effects of fishing on C. brachyurus may be more serious than its representation in the catch suggests. C. brachyurus and other Carcharhinus spp. are rare in California and do not support any directed fisheries (Bonfil 1994, Hanson 1999, R. Lea pers. comm., D. Ebert pers. comm., G. Cailliet pers. comm.).
Sport fisheries taking Carcharhinus spp. occur in New Zealand, Australia, South Africa, Argentina, Mexico and California (Stevens 1984, Compagno et al. 1989, Cappo 1992, Pepperell 1992, Appelgate et al. 1993, Francis 1998, Chiaramonte 1998a, b). In New Zealand C. brachyurus is the most commonly landed Carcharhinus species. It is only infrequently taken by anglers targeting marlin and swordfish off the northeast North Island. Most of these fish are unwanted and are released. However there is a small summer boat and shore-based sport fishery for C. brachyurus centered on the large harbours in the northern North Island. Most of the sharks taken in this fishery are pregnant and post-partum females and are tagged and released. A small number are retained and landed during fishing competitions. C. brachyurus are also occasionally taken by bow-hunters in some North Island harbours, and there are incidental catches of juveniles and adults in recreational gill net fisheries for rig (Mustelus lenticulatus), mullet, snapper and flatfish. The size of this bycatch is unknown but is probably minor. C. brachyurus is a minor component of sport fishing catches in southern New South Wales between Port Stephens and Narooma but is likely to dominate "bronze whaler" catches in Victoria and South Australia (Stevens 1984, Cappo 1992). No information on these fisheries was available at the time of writing. In South Africa this species is regularly taken by shore-based fishers in the Eastern Cape. These fishers take mainly neonates and juveniles less than 2 m total length (Smale 1991). There is also a land-based tag and release fishery for adult C. brachyurus in Nambia (S. Fowler pers. comm.).
C. brachyurus is commonly taken in protective shark control programs off Natal, South Africa and presumably Australia (New South Wales), although catches of Carcharhinus spp. are not identified to species in Australia (Cliff and Dudley 1992, Reid and Krogh 1992, Dudley 1997, Dudley et al. 1998). The mean annual catch in the Natal shark nets between 1978 and 1990 was 138 (range 9 to 421). Large annual fluctuations in catch meant no trend was evident over that period (Cliff and Dudley 1992). C. brachyurus is also killed as a pest species in and around fish farms, notably southern bluefin tuna pens in South Australia (I.G. pers. obs). The shallow coastal nursery areas of C. brachyurus are also potentially vulnerable to habitat loss and pollution arising from coastal development. The effects of this are likely to be greatest in parts of the Mediterranean Sea and East Asia. Expansion of marine aquaculture in New Zealand also potentially threatens nursery areas of C. brachyurus.
Castro et al. (1999) listed this species as Category 3 (i.e., a species that is exploited by directed fisheries or bycatch, and has a limited reproductive potential, and/or life history characteristics that makes it especially vulnerable to over fishing). Vidthayanon (2002) listed it as vulnerable in Thailand.
A prohibition on taking school and gummy sharks in shark nursery areas in Tasmania, and bans on gillnetting in some of these, may indirectly benefit some C. brachyurus but most of these areas are outside the main part of the species range (Williams and Schaap 1992, Last and Stevens 1994). Victorian coastal waters out to three nautical miles are almost completely closed to commercial shark fishing (Stevens 2002).
C. brachyurus may not be target fished in Quota Management Areas 1, 3, 4, 5, 6, 9. Management measures that are likely to indirectly benefit this species include closure of most harbours and semi-enclosed bays in northern New Zealand to trawling and Danish seining, and a permanent ban on gill netting out to five nautical miles from shore off the northwest North Island (Fisheries statistical areas 41 and 42) to protect endangered North Island Hector's dolphin.
Relevance to Humans and Ecosystems
The copper shark, bronze whaler, or narrowtooth shark (Carcharhinus brachyurus) is a species of requiem shark, family Carcharhinidae, and the only member of its genus found mostly at temperate latitudes. It is distributed in a number of separate populations in the northeastern and southwestern Atlantic, off southern Africa, in the northwestern and eastern Pacific, and around Australia and New Zealand, with scattered reports from equatorial regions. This species can be found from brackish rivers and estuaries, to shallow bays and harbors, to offshore waters 100 m (330 ft) deep or more. Females are found apart from males for most of the year, and conduct seasonal migrations. A large species reaching 3.3 m (11 ft) long, the copper shark is difficult to distinguish from other large requiem sharks. It is characterized by its narrow, hook-shaped upper teeth, lack of a prominent ridge between the dorsal fins, and plain bronze coloration.
Feeding mainly on cephalopods, bony fishes, and other cartilaginous fishes, the copper shark is a fast-swimming predator that often hunts in large groups, utilizing their numbers to their advantage. Off South Africa, this species associates closely with the annual sardine run, involving millions of southern African pilchard (Sardinops sagax). Like other requiem sharks, it is viviparous, with the developing embryos mainly nourished through a placental connection formed from the depleted yolk sac. Females bear litters of 7 to 24 pups every other year in coastal nursery areas, after a gestation period of 12 or perhaps as long as 21 months. It is extremely slow-growing, with males and females not reaching maturity until 13–19 and 19–20 years of age respectively.
This species is valued by commercial and recreational fisheries throughout its range, and utilized as food. The species population size is unknown, but the ICUN's Red List assesses the species as Near Threatened because it is very susceptible to population depletion due to its low growth and reproductive rates and because its numbers are believed to have declined in some areas.
Because of its very patchy range, the copper shark has been scientifically described several times from different locales. The earliest valid description is presently considered to be British zoologist Albert Günther's account of Carcharias brachyurus in the 1870 eighth volume of Catalogue of the fishes in the British Museum. The earliest name was once thought to be Auguste Duméril's 1865 Carcharias remotus, until it was found that the type specimen associated with that name is actually a blacknose shark (C. acronotus). Thus, this shark was often referred to as C. remotus in older literature. An even earlier name, Richard Owen's 1853 Galeolamna greyi, is of questionable taxonomic status as it was based solely on a set of now-destroyed jaws that may or may not have belonged to a copper shark. Modern authors have assigned this species to the genus Carcharhinus.
The specific epithet brachyurus is derived from the Greek brachys ("short") and oura ("tail"). The name "whaler" originated in the 19th century, applied by the crews of whaling vessels in the Pacific who saw large sharks of various species congregating around harpooned whale carcasses. This species may also be referred to as black-tipped whaler, cocktail shark or cocktail whaler, or New Zealand whaler, as well as by the shortened "bronze", "bronzie", or "cocktail". Günther originally referred to four syntypes: a stuffed specimen from Antarctica and another from New Zealand, which have since been lost, and two fetuses from Australia that were later discovered to be bull sharks (C. leucas). In the interests of taxonomic stability, in 1982 Jack Garrick designated a 2.4 m (7.9 ft) long female caught off Whanganui, New Zealand as a new type specimen.
Phylogeny and evolution
The first efforts to determine the evolutionary relationships of the copper shark were based on morphology and returned inconclusive results: in 1982 Jack Garrick placed it by itself as a grouping within Carcharhinus, while in 1988 Leonard Compagno placed it in an informal "transitional group" that also contained the blacknose shark (C. acronotus), the blacktip reef shark (C. melanopterus), the nervous shark (C. cautus), the silky shark (C. falciformis), and the night shark (C. signatus). Gavin Naylor's 1992 allozyme study concluded that the closest relative of the copper shark is the spinner shark (C. brevipinna), but could not resolve their wider relationships with the rest of the genus. Fossilized teeth from the copper shark have been recovered from the Pungo River in North Carolina, dating to the Miocene (23–5.3 Ma), from Tuscany, dating to the Pliocene (5.3–2.6 Ma), and from Costa Mesa in California, dating to the Late Pleistocene (126,000–12,000 years ago).
Distribution and habitat
The copper shark is the only member of its genus largely found in temperate rather than tropical waters, in temperatures above 12 °C (54 °F). It is widely distributed but as disjunct regional populations with little to no interchange between them. In the Atlantic, this shark occurs from the Mediterranean Sea to Morocco and the Canary Islands, off Argentina, and off Namibia and South Africa (where there may be two separate populations), with infrequent records from Mauritania, the Gulf of Guinea, and possibly the Gulf of Mexico. In the Indo-Pacific, it is found from the East China Sea to Japan (excluding Hokkaido) and southern Russia, off southern Australia (mostly between Sydney and Perth but occasionally further north), and around New Zealand but not as far as the Kermadec Islands; there are also unconfirmed reports from the Seychelles and the Gulf of Thailand. In the eastern Pacific, it occurs from northern Chile to Peru, and from Mexico to Point Conception, California, including the Gulf of California. The copper shark is common off parts of Argentina, South Africa, Australia, and New Zealand, and rare elsewhere; in many areas its range is ill-defined because of confusion with other species.
Copper sharks can be found from the surf zone to slightly beyond the continental shelf in the open ocean, diving to depths of 100 m (330 ft) or more. This species commonly enters very shallow habitats, including bays, shoals, and harbors, and also inhabits rocky areas and offshore islands. It is tolerant of low and changing salinities, and has been reported from estuaries and the lower reaches of large rivers. Juveniles inhabit inshore waters less than 30 m (98 ft) deep throughout the year, while adults tend to be found further offshore and regularly approach the coast only in spring and summer, when large aggregations can be readily observed in shallow water.
Populations of copper sharks in both hemispheres perform seasonal migrations, in response to temperature changes, reproductive events, and/or prey availability; the movement patterns differ with sex and age. Adult females and juveniles spend winter in the subtropics and generally shift to higher latitudes as spring nears, with pregnant females also moving towards the coast to give birth in inshore nursery areas. Adult males remain in the subtropics for most of the year, except in late winter or spring when they also move into higher latitudes, in time to encounter and mate with post-partum females dispersing from the nurseries. During migrations, individual sharks have been recorded traveling up to 1,320 km (820 mi). It is philopatric, returning to the same areas year after year.
The copper shark has a slender, streamlined body with a slightly arched profile just behind the head. The snout is rather long and pointed, with the nostrils preceded by low flaps of skin. The round, moderately large eyes are equipped with nictating membranes (protective third eyelids). The mouth has short, subtle furrows at the corners and contains 29–35 upper tooth rows and 29–33 lower tooth rows. The teeth are serrated with single narrow cusps; the upper teeth have a distinctive hooked shape and become more angled towards the corners of the jaw, while the lower teeth are upright. The upper teeth of adult males are longer, narrower, more curved, and more finely serrated than those of adult females and juveniles. The five pairs of gill slits are fairly long.
The pectoral fins are large, pointed, and falcate (sickle-shaped). The first dorsal fin is tall, with a pointed apex and a concave trailing margin; its origin lies about even with the tips of the pectoral fins. The second dorsal fin is small and low, and positioned about opposite to the anal fin. There is usually no ridge between the dorsal fins. The caudal fin has a well-developed lower lobe and a deep ventral notch near the tip of the upper lobe. This species is bronze to olive-gray above with a metallic sheen and sometimes a pink cast, darkening towards the fin tips and margins but not conspicuously so; the color fades quickly to a dull gray-brown after death. The underside is white, which extends onto the flanks as a prominent band. The copper shark is easily mistaken for other large Carcharhinus species, particularly the dusky shark (C. obscurus), but can be identified by its upper tooth shape, absent or weak interdorsal ridge, and lack of obvious fin markings. It reportedly reaches a maximum length of 3.3 m (11 ft) and weight of 305 kilograms (672 lb).
Biology and ecology
Fast and active, the copper shark may be encountered alone, in pairs, or in loosely organized schools containing up to hundreds of individuals. Some aggregations seem to form for reproductive purposes, while others form in response to concentrations of food. This species may fall prey to larger sharks. Known parasites of the copper shark include the tapeworms Cathetocephalus australis, Dasyrhynchus pacificus and D. talismani, Floriceps minacanthus, Phoreiobothrium robertsoni, and Pseudogrillotia spratti, the leech Stibarobdella macrothela, and the fluke Otodistomum veliporum.
The copper shark feeds more towards the bottom of the water column than the top, consuming cephalopods, including squid (Loligo spp.), cuttlefishes, and octopus; bony fishes, including gurnards, flatfishes, hakes, catfishes, jacks, Australian salmon, mullets, sea breams, smelts, tunas, sardines, and anchovies; and cartilaginous fishes, including dogfish sharks (Squalus spp.), stingrays, skates, electric rays, and sawfishes. Cephalopods and cartilaginous fishes become relatively more important food for sharks over 2 m (6.6 ft) long. Young sharks also consume scyphozoan jellyfish and crustaceans, including mud shrimps (Callianassa) and penaeid prawns. It does not attack marine mammals, though has been known rarely to scavenge on dolphins that had succumbed to fishing nets. The predominant prey of this species off South Africa is the southern African pilchard (Sardinops sagax), which comprise 69–95% of its diet. Every winter, schools of copper sharks follow the "run" of the pilchard from the Eastern Cape to KwaZulu-Natal. The gathering of millions of forage fish attract a multitude of predators, including several species of sharks, of which copper sharks are the most numerous.
Large numbers of copper sharks have been observed hunting together in a seemingly cooperative fashion. Small schooling fish are "herded" into a tight ball, whereupon each shark swims through in turn with its mouth open to feed. For groups of tuna and larger prey, the pursuing sharks may adopt a "wing" formation to force their quarry closer together, with each shark targeting a particular fish and attacking in turn. In False Bay, South Africa, this species reportedly follows seine net fishing vessels.
Like other members of its family, the copper shark is viviparous, in which the yolk sac of the developing embryo, once depleted, is converted into a placental connection through which the mother delivers nourishment. Adult females have one functional ovary, on the right, and two functional uteruses. The male bites the female as a prelude to mating. In the Southern Hemisphere, mating takes place from October to December (spring and early summer), when both sexes have migrated into offshore waters at higher latitudes. Birthing seems to occur from June to January, peaking in October and November.
Female copper sharks make use of shallow inshore habitats, varying from stretches of open coast to more sheltered bays and inlets, as nurseries. These nurseries provide abundant food and reduce the likelihood of predation by larger members of the species. Known and suspected nursery areas occur off northern North Island from Waimea Inlet to Hawke Bay for New Zealand sharks, off Albany, in and around Gulf St Vincent, and in Port Phillip Bay for Australian sharks, off Niigata (Japan) for northwestern Pacific sharks, off the Eastern Cape for South Africa sharks, off Rhodes (Greece), Nice (France), and Al Hoceima (Morocco) for Mediterranean sharks, off Río de Oro (Western Sahara) for northwest African sharks, off Rio de Janeiro (Brazil) and Buenos Aires and Bahía Blanca (Argentina) for southwestern Atlantic sharks, and off Paita and Guanape Cove (Peru), in Sebastián Vizcaíno Bay (Mexico), and in and around San Diego Bay for eastern Pacific sharks.
Most sources estimate a gestation period of 12 months, though some data support the interpretation of a 15–21 month long gestation period instead. Females produce litters every other year, with the number of pups ranging from 7 to 24 and averaging 15 or 16. Females off California and the Baja Peninsula tend to bear fewer young relative to other parts of the world. The newborns measure 55–67 cm (22–26 in) long. The copper shark is among the slowest-growing Carcharhinus species: off South Africa, males reach sexual maturity at 2.0–2.4 m (6.6–7.9 ft) long and an age of 13–19 years, while females mature at 2.3–2.5 m (7.5–8.2 ft) long and an age of 19–20 years. Females off Australia mature at a comparable length of 2.5 m (8.2 ft), while females off Argentina mature at a slightly smaller length of 2.2 m (7.2 ft). The maximum lifespan is at least 30 years for males and 25 years for females.
Attacks on Humans
Copper sharks attack humans infrequently, but the species places sixth in the number of unprovoked attacks on people. During the tracking period through 2013, the University of Florida attributed 20 attacks to the species. (In comparison, great white sharks topped the list, with 279 attacks.) Though large and powerful, the copper shark is not particularly aggressive towards humans unless in the presence of food. Copper Sharks have been known to harass and attack spear fishers in an attempt to steal catches. Copper sharks have bitten several swimmers in Australia and New Zealand, where the species is common. (The species is commonly called bronze whalers in this part of the world.)
Fatal attacks attributed to the copper shark (bronze whaler) include the 2014 death of a swimmer in Tathra, New South Wales, Australia, and the 1976 death of a swimmer in Te Kaha, New Zealand. Three out of ten shark attacks in New Zealand are attributed to Copper sharks. Witnesses also attributed a fatal attack on September 2011 in Bunker Bay, Western Australia to a copper shark.
One problem with counting attacks on humans is that the copper shark is so similar to other requiem sharks. Victims and witnesses are unlikely to correctly identify which type of genus Carcharhinus shark is responsible for the attack. Experts trying to confirm shark attacks by species warn that their statistics undercount the number of attacks by requiem sharks like the copper.
Like many large, active sharks, this species adapts poorly to captivity; it tends to bump into the sides of its enclosure, and the resulting abrasions then become infected with often fatal consequences.
Commercial fisheries for the copper shark exist off New Zealand, Australia (though the "bronze whaler fishery" of Western Australia actually takes mostly dusky sharks), South Africa, Brazil, Uruguay, Argentina, Mexico, and China; it also contributes to the bycatch of other commercial fisheries across its range. This species is caught in gillnets and on bottom longlines, and to a much lesser extent in bottom trawls and on pelagic longlines. The meat is sold for human consumption. The copper shark is also popular with recreational fishers in Namibia, New Zealand, Australia, South Africa, Argentina, Mexico and California, predominantly by anglers but also by bowfishers and gillnetters. In New Zealand, it is the Carcharhinus species most frequently caught by sport fishers and sustains a small, summer recreational fishery in northern North Island, that mainly captures pregnant and post-partum females and for the most part practices tag and release. A tag and release program is also practiced in Namibia.
The International Union for Conservation of Nature (IUCN) has assessed the copper shark as Near Threatened worldwide. While the global population is unknown, the long maturation time and low reproductive rate of this species render it highly susceptible to overfishing. Regionally, the IUCN has listed this species under Least Concern off Australia, New Zealand, and South Africa, where fisheries are generally well-managed; the local copper shark population for each of those three countries is contained almost entirely within their respective Exclusive Economic Zones (EEZ). Reported catches by New Zealand have steadily declined from a peak of 40 tons in 1995/96 to 20 tons 2001/02, though it is uncertain whether this reflects a genuine decline or changing fishing habits.
In the eastern Pacific, the copper shark is rare and little fishery information is available, leading to an assessment of Data Deficient. However, catch declines across all shark and ray species have been documented in the heavily-fished Gulf of California. Off East Asia, the copper shark has been assessed as Vulnerable; though species-specific data is unavailable, shark populations overall have been decimated in the region. The number of large adults have been too low to sustain targeted fisheries since the 1970s, and most of the current shark catch consists of small juveniles. Additional threats to this species include the degradation and destruction of its coastal nurseries from development, pollution, and aquaculture, mortality from shark nets used to protect beaches in South Africa and Australia, and persecution by fish farmers in southern Australia.
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No estimates of population size or biomass are available. Global population structure is unknown. Stock structure is not known for any fished population.
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- Anna Leask; Kieran Campbell; Andrew Koubaridis (Feb 27, 2013). "Shark victim named". New Zealand Herald.
He spoke of the concern he held for his friends when he saw a large bronze whaler shark, assuming his wife was already safely ashore.
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- "Shark Victim Named". NZ Herald.
A DECADE OF SHARK ATTACKS IN NZ
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- Burgess, George. "ISAF Statistics on Attacking Species of Shark". International Shark Attack File Florida Museum of Natural History, University of Florida. Retrieved 12 April 2014.
Positive identification of attacking sharks is very difficult since victims rarely make adequate observations of the attacker during the "heat" of the interaction. Tooth remains are seldom found in wounds and diagnostic characters for many requiem sharks (family Carcharhinidae) are difficult to discern even by trained professionals. That said, this list must be used with caution because attacks involving easily identified species, such as white, tiger, sandtiger, hammerhead and nurse sharks, nearly always identify the attacking species, while cases involving difficult to identify species, such as requiem sharks of the genus Carcharhinus, seldom correctly identify the attacker. Thus the list is skewed to readily identified species.
- "ISAF Statistics on Attacking Species of Shark". International Shark Attack File Florida Museum of Natural History, University of Florida. Retrieved 12 April 2014.
A number of requiem sharks in the genus Carcharhinus likely are involved in many more attacks than they are credited in this list and, if the list could reflect that reality, Carcharhinus bites would push such species as the sandtiger, hammerhead and nurse sharks towards the bottom of the list.