A shark at an Aberdeenshire aquarium has laid a “very rare” twin egg.
A dogfish shark at Macduff Marine Aquarium laid the unusual double-yolked egg in the centre’s kelp tank on Wednesday.
Aquarium staff have been raising dogfish for 16 years, but this is the first time a double-yolked mermaid’s purse has been discovered.
Macduff Aquarium shark expert, Dr Lauren Smith, said it may even be a world first for a dogfish held in captivity.
Dr Smith said: “I have been studying and working with sharks for nearly ten years and have never seen or heard of twins in this species.
“The female normally lays two hard egg capsules in quick succession, but not normally two eggs in one purse.
“There are no reports of this phenomenon that I can find in the literature. This could be a first and we’re very excited to see how it develops.”
A young dogfish starts life as a tiny embryo nourished by a yolk sac within the mermaid’s purse and can take up to nine months to hatch.
Every year aquarium staff release dogfish into the wild near Macduff to boost local populations.