Shark discovered hiding in aquarium

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Stunned aquarium staff in the UK have discovered something they didn't know was in their tank - an extra shark.

The shark has been living undetected in their ocean tank for years.

Staff at Blackpool Sea Life Centre in England were baffled when two shark eggs were discovered in a tank occupied by resident sharks which give birth only to live young.

The centre's marine experts speculate that one of several former curators must have introduced a small tropical carpet shark to the display without recording the fact, and it has been in hiding ever since.

- AAP