Shark who hasn't been kept with male since 2019 gives birth at US zoo

A baby shark has been born in the US without a father - but not because he swam away.

Last week, the Chicago Zoological Society announced a baby epaulette shark pup had hatched at Brookfield Zoo.

This was considered somewhat unusual as its mother had not been housed with a male shark since arriving at the zoo as a three-year-old in 2019.

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Epaulette sharks usually begin reproducing at around seven years.

Last year, the society said, the female had begun laying monthly clutches of infertile eggs.

However one, after incubating for five months, hatched out the pup in August, the culmination of a process known as parthenogenesis whereby an embryo develops from an unfertilised egg cell.

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Now about two and a half months old, the shark measures about 15cm and is expected to reach about 75cm to 90cm in length when fully grown.

Parthenogenesis is a natural occurrence in some invertebrates, but less so in complex vertebrates, including sharks.

"We are happy to report that our epaulette pup has been eating well on her diet of finely chopped capelin, minced squid tentacles, and other finely chopped seafood," said Mike Masellis, a lead animal care specialist at Brookfield Zoo.

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Our colleagues at New England Aquarium have been a great resource as shark pups produced parthenogenetically can be very delicate.

"We are looking forward to guests being able to see the pup."

Epaulette sharks are usually found in warm, shallow waters off Australia.