Primorsky Aquarium becomes the first in Russia to breed an ancient shark species
A baby zebra bullhead shark (Heterodontus zebra) has hatched at the Primorsky Aquarium – it is the first successful breeding of this shark species in Russia.
The egg from which the pup emerged had been deposited by the mother shark in January, thus the incubation, i.e. the development of the embryo in the egg case before hatching, lasted for 11 months. But our aquarists have been waiting for the birth of this pup much longer ̶ for three years.
“The zebra bullhead shark breeding program has been run at the Primorsky Aquarium since 2018,” explained Natalia Gireva, Head of the Tropical Marine Species Department. “Very few public aquariums in the world keep Heterodontus zebra. This shark is not adequately studied, and it is very important to understand its reproductive biology. There are five adult bullhead sharks at the Primorsky Aquarium: three females and two males. The elder female has already had three reproductive cycles, each cycle producing 6-8 batches of eggs. All of these eggs have so far been unfertilized, but we’ve been repeatedly observing the fish’s behavior and fine-tuning incubation conditions, and at last – you see – there are six zebra bullhead sharks at the aquarium!”
The length of the young is 177 mm from the tip of the snout to the tip of the tail and the weight is 35 g. It chewed itself out of the egg case as a fully developed baby shark, able to swim around. Outwardly the pup looks very much like the parents, but its fins are larger in relation to the body and the coloration is brighter: while adults have light and dark brown vertical stripes, the stripes of the young are cream and black.
The zebra bullhead shark, or the striped bullhead shark, belongs to the genus Heterodontus, which altogether includes nine species and is one of the most ancient genera of modern sharks. These fish appeared about 242 million years ago and did not change much since the age of dinosaurs.