Baby Shark Twins Born in the UK for First Time

Baby shark twins successfully born in the UK for the first time are celebrating their first anniversary in a major milestone for British marine conservation and breeding programmes.

Aquarists at SEA LIFE Blackpool are delighted both of the blacktip reef pups have safely reached this landmark birthday, after a year of delicate care and close supervision.  It involved the tricky task of weighing and measuring them to record their progress.

Some nights aquarists even slept over at the aquarium to monitor the remarkable pair.  In the wild the survival rate of baby sharks is less than one in 10, with shark populations falling and many species now endangered or threatened.

It marks an important step forward as in the wild most shark pups die shortly after birth, facing threats from larger predators including other sharks and even their own mother!

Unusually in the natural world, shark pups have to be completely independent, hunting and feeding themselves, right from birth.

The pups, who have their own nursery display, which is hugely popular with visitors who can observe them close up. They look exactly like miniature sharks, with all the tell-tale signs.

Named Koda and Cleo, they now measure almost twice as big as when they were born. Male pup Koda is now 75 centimetres (cms) long, while female pup Cleo is fractionally bigger at 76 cms.  Similarly, their weight has almost doubled, increasing to 6.5 kilograms (kgs) for Koda and 5.6 kgs for Cleo.  It involved a highly-skilled operation to carefully catch each shark pup in a giant net and then weigh and measure them, using a weighing device and tape measure!

Matthew Titherington, general manager at SEA LIFE Blackpool, said: “This is an important moment. Baby sharks really struggle to survive in the wild, compounding already falling numbers due to shark fishing. I’m incredibly proud of the team and their achievement in successfully rearing the first shark pup twins to their first birthday. They are both in great health, excellent condition and continue to grow well.

“These were the first shark pup twins born in the UK. We are dedicated to providing the best possible care for the many species we house here, but more than that want to do everything we can to support populations of these vulnerable species. Our shark pup twins provide a valuable boost to research surrounding this species, as well as strengthening breeding programmes across Europe, helping to safeguard shark populations.”

The twins are fed twice a day and their favourite food is fresh mackerel.

It’s an extraordinary success story and highlight’s SEA LIFE Blackpool’s role as a marine breeding and conservation centre, as part of its ‘breed, rescue, protect’ campaign. It is now the hub for all blacktip reef breeding programmes across Europe. Aquarium curator Scott Blacker and his team provided round-the-clock care for the pups during their crucial first days.

He said: “To have both pups healthy and continuing to grow well after their crucial first year is a huge result for all of the aquarists and wider team here. I’d like to thank them all for their commitment and hard work. Long nights and careful monitoring have been required to provide the best possible care for the twins. We’re delighted to have reach this milestone,” he added.

Last year they were safely delivered in a special birthing area, screened off from other creatures, after five years in the planning. Aquarists supervised both births before immediately removing the pups for their safety to a special quarantine tank.  This had followed meticulous planning over the previous 12 months to try to identify when female sharks were pregnant and at what stage – a notoriously difficult task for marine experts.

A detailed plan was developed for every stage of the pregnancy, birth and nursery stage, including diet and welfare. A special area was created within the main shark display, where the female could be looked after, when curator Scott and his team believed the expectant shark was in the later stages of pregnancy. Aquarists monitored the small pups round the clock for the first few days, hand-feeding pieces of fresh salmon to them, to encourage them to start feeding.

It marked a big breakthrough as the important first ‘litter’ to have been born in the UK. Visitors can now see them swimming together in the special shark nursery area.

The International Union for Conservation of Nature has officially listed blacktip reef sharks as near threatened. Significant local declines in some parts of the world have been seen in recent years, primarily caused by overfishing and plastic pollution. Their low reproductive rate means shark populations can struggle to recover from depleted numbers.

Blacktip reef sharks give birth to live young and the specific details of their early life vary depending on the regions they live in. Gestation periods vary between seven to eight months off Australia to up to 11 months in the Indian and Pacific oceans.

Young blacktips develop exceptionally quickly, growing by up to nine inches per year during their first two years of life and gaining weight at a rate of 100 grams per week. Some blacktip reef shark populations living around specific tropical islands have been decimated by overfishing, chiefly for their fins, which are highly prized in China for shark-fin soup. 

SEA LIFE Blackpool works closely with its charity partner, the Sea Life Trust, as part of its popular 'breed, rescue, protect' campaign, to develop and support ocean conservation projects worldwide, including threatened and endangered species, such as turtles, sharks and sea horses.