.
ReShark, the world’s first shark rewilding program and which Eerdman heads up, is bringing these reef sharks back one egg at a time.
“The reefs were recovering well, the reef fishes were recovering well, but the sharks were taking a bit longer, because they’d been hit so hard, so they started the movement to create a shark and ray sanctuary in Raja”, he told RNZ’s Nine to Noon .
Leopard sharks, which are native to Indo-Pacific waters, once thrived in the shallow coral reefs of Raja Ampat, but demand for their distinctive long tails in the shark fin trade decimated populations.
Things started to look up when Raja Ampat became the first shark and ray sanctuary in Southeast Asia in 2012.
Erdmann was visiting Singapore Aquarium in 2015 when he realised there might be a solution to Raja Ampat’s declining leopard shark population.
“They had this just enormous number of leopard shark pups that had recently hatched, and it was actually becoming a problem for them.”
While doing poorly in the wild leopard sharks were reproducing “literally like rabbits” In captivity, he says.
Over the next five years, in association with a number of aquariums throughout the world, a plan was hatched to transport eggs laid in aquariums back to the wild.
It’s a complex procedure, he says.
The eggs are incubated for two months in their home aquarium before being shipped to Raja Ampat, he says, packed in hyper-oxygenated water before eventually being taken by speedboat to one of of two custom-built nurseries.
A leopard shark swims near the water surface after being released in Misool, Raja Ampat.
Mark Erdmann
There, they are taken care of by ‘shark nannies’.
“Basically they’re aquarists, they’re women mostly, though a few guys, who have been purpose-trained in how to raise these animals, and they are now some of the world’s top experts in leopard shark husbandry.”
These nannies incubate the eggs and once hatched make sure the shark pups are fed on a diet of live food, he says.
“Their first food will be snails, actually, and you’d be amazed within hours of hatching, these little shark pups are quite proficient at literally sucking the snails out of their shells, a little escargot in the morning, and they can get to the point where they’re eating up to 100 snails a day, and growing very quickly, I might add.”
Eventually the sharks are transferred to a sea pen and are tagged and released into the wild at somewhere between five to eight months of age.
Some 68 pups have now been released in Raja Ampat with the aim to get to 500.
“Based on modelling, we believe that that will get us to a point where it is very much a self-sustaining breeding population.”
Members of the Women Divers Association of Raja Ampat.
ReShark
The recovering leopard shark population has also proved a tourism boon, he says
“It’s not a bitey, bitey shark. No one gets angry about having more leopard sharks around. They’re a beautiful bottom shark, they’re harmless, and quite frankly, they are a strong tourism asset for the region.”
