a new creature is added to this page monthly. just click on the thumbnail images below:

Bronze whaler…the 'New Zealand Shark'
Dave Abbott/ Clinton Duffy

Taxonomic key:

Kingdom: Animalia
Phylum: Chordata
Class: Elasmobranches
Order:
Family: Charcharinidae
Genus: Carcharhinus
Species: brachyurus

Introduction
The bronze whaler or copper shark (Carcharhinus brachyurus) was first described scientifically from specimens collected in New Zealand waters, and was originally known as the New Zealand whaler. At 2.8 -3.4m in length It is one of the largest of reef shark species, and one of the most abundant large shark species occurring in New Zealand coastal waters. It is also the only Carcharhinus species likely to be encountered by divers around mainland New Zealand.

Distribution
This is a widespread species in warm temperate waters and some tropical seas, with confirmed records from the Mediterranean Sea, parts of the African coast, Brazil, Argentina, Peru, California, Japan, China, Korea, New Zealand and southern Australia. In New Zealand bronze whalers (usually shortened to "Bronzie") are most abundant north of Cook Strait, although it is possible they may reach Foveaux Strait and Stewart Island during summer months.

Biology
The biology of the bronze whaler is poorly known due to confusion with other Carcharhinus species. In South Africa males are reported to mature at about 235 cm, and females at about 245 cm. Age at maturity is reported to be five years off South Africa. Reproduction is viviparous, and litters are reported to range from 7 to 20. Size at birth is 60 cm to 70 cm. Pupping appears to occur in shallow coastal waters, including harbours and large inlets, during late spring-early summer. Large schools of bronze whalers, sometimes numbering hundreds of individuals, sighted inshore near the mouths of large harbours and estuaries in northern New Zealand at this time may be breeding aggregations, and after pupping the females may move offshore to mate. Recent diver observations at the Poor Knights Islands [see 'Shark Research' page] and reports of multiple captures of bronze whalers by game fishermen on the Middlesex Bank and Three Kings Rise during winter suggest these offshore habitats may be important winter feeding grounds.

Conservation
The conservation status of bronze whaler populations worldwide is unknown. Although not thought to be threatened, Bronze whalers are likely to have low resilience to targeted commercial fishing. In New Zealand adults and juveniles are taken as bycatch in commercial and recreational gill net and line fisheries, and despite low reported commercial landings of fins and meat, misidentification and non-reporting of catch could give a false impression of the full impact of these fisheries. Recreational fishers occasionally target this species during fishing competitions, but generally most recreational captures are accidental. The breeding aggregations and nursery areas of Bronze whalers are also vulnerable, with recreational and commercial gill netting common in almost all of the known New Zealand nursery areas, while the catchments of most large harbours and estuaries in their range are subject to continuing development and urbanisation.

Although public awareness of the need to conserve shark populations/ end practices such as shark 'finning' is growing in New Zealand, there is much yet to be done if the survival of Bronze whaler and other shark populations are to be ensured. Sharks are spectacular and beautiful creatures when seen in their own environment.

For more details on 'Eye on the Sea's bronze whaler research project or additional information on sharks in general check out our Shark Research page.