An octopus at Bristol Aquarium is being set a series of increasingly complex tests and puzzles – with the help of giant water coolers.

Keepers at the Harbourside wildlife attraction are placing food items and treats inside the large, transparent containers to see how quickly Velcro – a giant Pacific octopus with a two-metre tentacle span – can work out how to get to them.

Already he has been able to use his long tentacles to extract food through the water cooler bottles narrow opening and now aquarists are planning to devise a series of more complex challenges.

Bristol Aquarium’s Mike Coe said: “Our aquarists are constantly providing Velcro with different sets of challenges, puzzles and other mental stimuli as part of an ongoing environmental enrichment programme.

“In the wild octopus have to use extraordinary dexterity and ingenuity to hunt and catch their prey and these types of puzzles and tests mimic those sort of challenges.

“Initially we were planning to use the water coolers, which were donated by local company Office Water Coolers South West, to help siphon water from our tanks but Velcro showed such an interest in them when they were first put into his display that we decided to utilise them as puzzles,” he added.

Giant Pacific octopuses are the world’s largest octopus species and are found from Japan to Southern California. The biggest recorded specimen had an arm span of 10 metres (33ft) and weighed 270kgs (600lbs).

Despite being closely related to the garden slug, octopus are believed to be as intelligent as pet dogs and can solve complex puzzles.

Individuals living in aquariums have been filmed sneaking out at night to raid nearby fish-filled displays. They mature incredibly quickly – going from the size of a rice grain at birth to being fully grown within the space of two years.