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BiologyDespite the bronze whaler being a fairly common species, its biology is relatively poorly known due to confusion with other species (3). It is a viviparous shark, and thus the embryos develop within the mother and are provided nutrition via a yolk-sac placenta. Gestation is thought to last for about one year, after which a litter of 13 to 24 pups, measuring 59 to 70 centimetres, are born. Male bronze whalers reach maturity at around 13 years; females are mature at around 20 years (5). Schools of adult and juvenile bronze whalers appear to segregate. Juveniles are present in shallow water all year round, whilst adults are found inshore only in spring and summer. Adult males occur in subtropical regions throughout the year, whereas females and immature sharks migrate to these regions during winter, and then return to temperate regions (and inshore) in the spring to breed (1). However, despite this migration, there is very little movement between adjacent regional populations (5). 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 (1). Bronze whalers can be found singly, or in loose schools of up to one hundred individuals (1). They feed on bony fishes, such as sardines, mullets, hake and soles, as well as other prey such as sawfish, squid and cuttlefish (3) (5). Large numbers follow the winter sardine run off the southern Natal coast, South Africa to feast on one of their preferred prey (5). This powerful and fast shark is considered to be a dangerous species, and there have been a few provoked and unprovoked attacks on swimmers and divers (3).