International Octopus Day

8 October was International Octopus Day and kicked off Cephalopod Awareness Week. Perhaps the reason octopuses have their very own special day is because they have the highest brain-to-body mass ratio of all invertebrates, or because they practise observational learning.

Shera, one of the resident octopuses at uShaka Sea World

The consensus, however, among uShaka Sea World staff as to why octopuses have their very own day is simply because they are just so interesting.

In the aquarium you will find Shera, an adult female octopus, in one of the exhibits as you enter Snorkel Lagoon. She was given the name Shera from the Masters of the Universe TV series as she is particularly strong. Octopuses can exert a force greater than their own body weight, and Shera proved no exception to this.

Shera is a common octopus (Octopus vulgaris) which, as their name implies, are commonly found worldwide near the tropics. Ask anyone who has worked with octopuses in aquaria and they will tell you that each octopus has an individual personality and responds differently to threatening, feeding and alerting behaviours. They are shy, blasé, active or passive, and either reactive or proactive.

Shera loves to play and even has a favourite colour – yellow.

All cephalopods are active predators and need to locate and capture their prey, which has probably been the driving force behind the development of their intelligence. At 15 months Shera is a fully grown adult but, with a naturally short lifespan of around 18 months, she is by our standards an older lady.

Having three beating hearts, thousands of highly sensitive suction cups, eight prehensile, dexterous arms (essential for tool use and manipulation) as well as the capacity to change skin colour and texture through nervous control of chromatophores means that, although their lifespans are short, they are well suited to thrive.

Young visitors (left to right) Jordan Nieuwenhuys (9) and Cullan Rush (6) comfortably settled at the exhibit window, mesmerised by Shera the octopus

This does not guarantee they will thrive indefinitely. More than 50 000 tons of octopus are caught each year. Octopuses have only recently been added to the SASSI List, as they are caught as bycatch and are consequently vulnerable to overfishing.

The favourite diet of most octopus species is crabs and, according to Shera’s principal aquarist, Jose Ganness, who has trained her using three different hand signals, she differs from the majority and prefers prawns to crabs. She also enjoys mussels.

Asked whether he believes that octopuses are intelligent creatures, Ganness replies: “For an animal without a backbone, Shera most certainly outsmarts any other creature I have worked with with no backbone. It only took her a week to interpret three different hand signals given to indicate movement to another part of the exhibit.

"It is commonly known that dolphins and seals respond to human hand signals with training; well, so can octopuses – but they learn much faster,” said Ganess.

We love octopuses – we just don’t hug them.

Bony fish

There is a great diversity of bony fish species. Some…

Meet our dolphins

Gambit is believed to be the largest bottlenose dolphin in…

Gambit the dolphin – a living legend at 41

A special birthday is being celebrated today at uShaka Sea…

Sardines

Sardines are small silver fish that are also known as…

Mazda Wildlife Fund supports ORI Coral Reef Research

The Mazda Wildlife Fund has supported the Oceanographic Research Institute’s…

uShaka Sea World is celebrating African Penguin Awareness Day on Saturday 8th October 2011

Penguins are our business. We all need healthy oceans to…

Why care about the oceans?

Not many people realise that carbon emissions are harming the…

Eco House opens in February

The Eco House in the aquarium will show you how…