Roving octopus to be freed

Sid's great escape from the Portobello Aquarium is about to become permanent.

The octopus, the aquarium's star attraction, mysteriously vanished from his tank last month.

Five frustrating days later, a baffled staff member spotted Sid making a dash for the door, said Tessa Mills, manager at the New Zealand Marine Studies Centre, which incorporates the Westpac Aquarium.

All the time, Sid had been using a seawater drain - part of the system used to pump fresh sea water through the aquarium - in a bid to reach the facility's sea water ponds outside.

"With a little gentle persuasion, Sid was finally back home in his tank, hungry but otherwise fine," Ms Mills said.

The sliding doors which provided access to a plastic case over his aquarium tank were now kept tightly closed.

"Once an octopus has learnt to escape, they have a tendency to continue escaping.

"We are still trying to catch a new octopus to replace Sid, who will then be set free."

Aquarist Dr Jean McKinnon said: "Sid's got quite good eyesight. We're watching him and he's watching us".

Aquarium senior aquarist Matthew Crane said an octopus's problem-solving ability made escape-proofing its tank "quite a challenge".

About 10 years ago, an octopus at the aquarium named Harry - after human escape artist Harry Houdini - escaped from the same tank now occupied by Sid, and was halfway up the steps to the nearby University of Otago marine laboratory when found.