Sharks and rays all belong to the same group of cartilaginous fishes- the elasmobranches. Unlike other fishes their skeletons are not made from bone but from flexible cartilage. At S.E.A. Aquarium we are fortunate to care for over 40 species of sharks and rays.
Sharks and rays are highly threatened by unsustainable fishing practices and are targeted for their fins and their meat. As they produce few young, grow slowly and reach late maturity they are susceptible and cannot easily recover from this fishing pressure. Many of the species at S.E.A. Aquarium are listed as Vulnerable or Near Threatened on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. It is therefore important to raise public awareness for these species in an attempt to help protect them in the natural environment.
Using in-house expertise we aim to mimic the natural environment and create the optimum conditions for reproduction. Our sharks and rays are so comfortable in our large habitats that they are mating instinctively and producing healthy young. The success of our current breeding programs is an encouraging step forward towards our larger conservation effort.
To date our in-house breeding includes six species of shark and four species of ray:
- Zebra sharks (Stegostoma fasciatum)
- Epaulette sharks (Hemiscyllium ocellatum)
- Whitespotted bamboo sharks (Chiloscyllium plagiosum)
- Brownbanded bamboo sharks (Chiloscyllium punctatum)
- Indonesian bamboo shark (Chiloscyllium hasselti)
- Bonnethead sharks (Sphyrna tiburo
- Blackbotched stingray (Taeniura meyeni)
- Whip stingray (Dasyatis akajei
- Blue-spotted stingray (Neotrygon kuhlii)
Breeding of Zebra Shark
Zebra sharks (Stegostoma fasciatum) are broadly distributed bottom dwelling sharks typically found on shallow coral reefs and sandy flats. Female zebra sharks produce egg cases in which fertilised eggs can grow and develop. The egg case will be attached to fixed structures such as coral or rock using it’s naturally produced sticky fibers called ‘tendrils’. The juvenile shark will remain in the egg cases until they are ready to hatch as fully developed sharks.
As zebra sharks are found on shallow reefs they are affected by the damage caused by inshore fisheries. Not all zebra shark populations are in decline. In Australia, they have a wide distribution and are caught in small numbers. Populations, however, have declined in areas where they are fished for their fins and meat, particularly areas such as Malaysia, Thailand and Indonesia. Zebra sharks are listed as Vulnerable on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species.
The aim is to study their growth and development so as to better understand the reproductive biology and growth of these animals under human care. Egg capsules are collected and transferred to a hatchery. During this time they are monitored by the team who ensure their conditions are optimal and stable. Upon hatching, the sharks will be transferred to a nursery habitat where the juvenile sharks are given the chance to develop without the concern of natural predation from other animals.
By successfully reproducing these animals we can exchange them with other facilities to increase the genetic diversity, which is important to prevent inbreeding in animals under human care. By breeding these sharks we can also exchange them with other facilities to reduce the impact on wild populations. Being able to study the development of these animals allows us to increase our understanding of their reproductive strategies and develop our in-house husbandry methods.