REPRODUCTION
Although we know little about their breeding, we now know that whale sharks produce live young which hatch from eggs within the mother's body. With this mode of reproducing they are said to be ovoviparous. A pregnant female caught off Taiwan weighing 16 tons and measuring 11m in length, contained 300 embryos. It is thought that the young are about 60 cm long at birth.
Their growth rate is slow and they mature late at about 20-25 years when they are about 9 metres long.

DISTRIBUTION
Globally, whale sharks are inhabitants of the tropical and warm - temperate oceans, preferring waters of 21 degrees to 25 degrees centigrade. They are believed to migrate to areas rich in food. They tend to concentrate at certain places at the same time each year - such as off the KwaZulu-Natal coastline in the latter part of summer. One of the purposes of tagging whale sharks is to confirm this. We do not know if there are separate populations in each of the major oceans, or whether there is dispersal from ocean to ocean. Again, tagging will provide insights into their distribution.

CONSERVATION
Whale sharks are vulnerable to fishing. With an increase in popularity of whale shark meat, a fishery for whale sharks has developed off the coast of Taiwan. In this fishery about 250 are killed each year by means of harpoons or set nets. They are also fished off Asia, India and Korea. However, whale sharks are now a protected species in the Phillipines and in the Maldives.
Their seasonal occurrence in South African waters is regarded as an important attraction for ecotourism. The conservation challenge is how to look after these animals which are slow to reproduce, take a long time to mature and possibly have high mortality of juveniles.

Rudy van der Elst and Bruce Mann are acknowledged for the scientific information on which this web page is based.