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Bristol Blue Reef Aquarium sees 'birth' of baby sharks
Shark and ray cases at Bristol's Blue Reef Aquarium
Staff have had an unexpected supply of eggs Bristol's Blue Reef Aquarium

Staff at Bristol's aquarium have had an early Easter present in the shape of dozens of egg-cases.

The egg-cases - which are also known as mermaid's purses - are being collected from the Blue Reef Aquarium's native giant harbourside display.

They will then be moved to special nursery tanks where they will be able to grow and develop safe from the unwanted attentions of the other fish.

The eggs have been laid by the attraction's sharks and rays.

Among the native shark species laying eggs are a number of dogfish that were themselves hatched at one of Blue Reef's sister aquariums several years ago.

Blue Reef's Dan de Castro said: "We've seen a steady increase in the numbers of eggs being produced over recent weeks and it's rapidly becoming a full time job for us just to keep collecting them.

"Not all the eggs will be fertile but we're confident that quite a number are and we can already see the tiny sharks wriggling about inside some of the protective egg-cases.

Shark and ray cases at Bristol's Blue Reef Aquarium
Dozens of egg-cases, also known as mermaid's purses, have been spotted

"It will be particularly good to be able to show people just how small most species of shark are when they are born and how long they take to develop.

"This slow development is a major cause of concern as it means they are vulnerable to over-fishing and by-catch."

Young dogfish are about 10cm long when they eventually hatch, after spending up to 11 months developing inside the egg capsule.

Each capsule is usually secured to rocks or seaweed by tendrils which prevent it from being washed away by tides or currents.

Once the sharks have hatched the empty egg-cases are often found washed ashore on beaches.

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