A young Great white shark temporarily housed at the Monterey Bay Aquarium has died just nine days after it was released back into the Pacific.
Jon Hoech, the Aquarium's director of husbandry announced the sad news saying: "This is a very difficult day for all of us, and for everyone who saw and cared about this animal. Based on the shark's behaviour and condition prior to release, we had every confidence that he'd do well back in the wild. Unfortunately, that's not how things turned out. We're surprised and saddened by the outcome."
The shark had been resident in the popular attraction's million gallon 'Open Ocean' exhibit for 55 days, growing 5cm/2" in length and gaining nearly nine pounds in weight during its stay, but aquarium staff took the decision to release it back into the wild when it was seen was rubbing itself against the exhibit's sides which they feared might cause abrasions that could become infected.
The shark had electronic tags attached prior to its release, but one of these popped free on October 29. The tags are designed to do this only when the shark hasn't moved for four days, indicating the shark died very soon after release. The scientific team behind the tagging are now studying the data contained in the retrieved tag. It's not known what killed the shark but entanglement in fishing nets, being hit by a boat, attack by another shark or an unknown illness, undetected before its release, are all being considered.
The Aquarium's vet, Dr. Mike Murray said: "Our first concern is always the health and well-being of the animals under our care. It became clear that it was time to release him. While we determined it was best not to keep him on exhibit any longer, we had no reservations about whether the shark would do well in the wild. That's why his death is both distressing and puzzling."
The shark was the sixth specimen kept by the aquarium, with all the previous fish being successfully released with tags back into the wild, the only previous fatality occurring four months after release when one was killed in fishing nets.
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