WHALE SHARK REPRODUCTION

Historically, there was great scientific debate about the mode of development of whale sharks. It was unclear whether it is oviparous (egg cases expelled from the female’s body and hatched on the sea floor) or ovoviviparous (egg cases hatching in the mother’s uteri, with the female giving birth to live young).

Finally in 1995, an 11-meter female whale shark was harpooned off the eastern coast of Taiwan and 300 fetal specimens, ranging in length from 42 to 63cm, were taken from the two uteri.

This discovery proved that the species is a live bearer, with an ovoviviparous mode of development. The egg-capsules of this whale shark were amber colored, with a smooth texture, and possessed a respiratory fissure (opening) on each side. The sex ratio was approximately 1:1.
It would appear that female whale sharks give birth as they feed in the rich waters of the Kuroshio Current. It is also apparent that the southeast waters off Taiwan are an important birthing area during summer months.