A female zebra shark (Stegostoma fasciatum) has hatched at The Deep, Hull’s award-winning aquarium, a first of its kind for the attraction. The shark, which was only 23cm long (72 grams) upon hatching, is growing steadily.
Zebra sharks take a long time to mature, so The Deep was delighted when mating behaviour, and ‘practice eggs’ were finally seen in the Endless Oceans display. ‘Practice eggs’ which do not contain a yolk are the first signs that a female shark is maturing.
Katy Duke, Curator at The Deep said “The team here were very excited at the prospect of eggs, and sure enough after a few months, an egg with a yolk was found. The egg was placed into a holding tank in our quarantine area and watched closely for signs of development.
“We used a technique called ‘candling’, which is where you shine a light through the egg casing underwater and we were absolutely delighted to see a shark embryo in there. Later on in her development our Vet and Science Officer used an ultrasound to take a better look inside the egg and was able to measure the size of the baby sharks heart which was 6mm in diameter – the size of a pea.
“She hatched out early on Monday morning – in fact, on our first check of the egg that day there appeared to be no change; however minutes later she had pushed her way out.
“She is doing very well and although these first few months are a delicate time, she is enjoying feeding on prawns and mussels and has grown to 25cms. We have taken some advice from colleagues in America on feeding and growth rates, so we are able to provide the best possible care.”
The gestation period for this type of shark is around 6 months in the egg. When zebra sharks hatch they have black and white stripes, which develop into more of a leopard print later in life, giving them their other name of leopard shark.
The Deep currently holds the European studbook for zebra sharks, so this newest arrival is a fantastic achievement. The studbook helps to coordinate all the breeding efforts for this species across Europe sharing vital knowledge on their reproductive biology.
The zebra shark will be kept at The Deep while her growth rates are closely monitored. Eventually she will likely be transferred to a new home at another aquarium so she can be paired with an unrelated mail and one day lay her own eggs.
See The Deep’s Facebook page at www.facebook.com/TheDeepHull