Kate Lee releases a captive-bred juvenile wobbegong shark into Cabbage Tree Bay Aquatic Reserve, Manly. Photo: Sea Life Conservation Fund
Sharks are very misunderstood animals and receive a largely undeserved reputation as vicious animals, although they have a unique "sixth sense" that allows them to locate their true, much smaller, prey.
These are some of the findings from research conducted by the Sydney Aquarium into shark behaviour.
There are more than 350 species of shark, but only four or five are considered to be dangerous to humans, the aquarium says.
A juvenile wobbegong shark, born in captivity at Sydney Aquarium as part of Sea Life Conservation Fund’s breeding program, is released into Cabbage Tree Bay Aquatic Reserve, Manly. Photo: Sea Life Conservation Fund
For most sharks something as big as a human would not be considered as prey as we are too large, it says.
Instead they may think of us as a threat and prefer to stay as far away as possible.
Attacks on humans in the wild are not as common as the media would indicate, and deaths are even rarer, the aquarium says.
Rays move to new home
Sydney Aquarium aquarists conduct a meticulous operation to capture and move an enormous leopard ray from its old to its new home. Photo: Kent Miklenda
No shark is thought to target humans as prey.
In most cases where a person is bitten, it is a case of mistaken identity, the aquarium says.
For the most part, sharks are generally placid animals and not to be feared.
From left to right: Marty Garwood, Rob Harcourt, Vic Peddemors, Kate Lee (holding the wobbegong shark), Marija Honkavaara, Claudette Rechtorik and Rob Townsend, getting ready to release the shark into Cabbage Tree Bay Aquatic Reserve in Manly. Photo: Sea Life Conservation Fund
This month, the Sydney Aquarium is relaunching as the SEA LIFE Sydney Aquarium following a $10 million overhaul.
The aquarium will become home to the largest variety of sharks and rays in the world.
In conjunction with its conservation arm, the Sydney Aquarium Conservation Fund, the attraction has completed research on the grey nurse and wobbegong sharks.
Among the findings:
- Sharks have a sixth sense, called electroreception. The underside of the grey nurse shark's snout is dotted with pores. Each of these leads to an organ (ampulae of Lorenzini) that can detect electricity.
- The electroreception capabilities of sharks gives them the ability to detect and attack prey at close range without needing to see the prey as well as navigate using the earth's magnetic field.
- The grey nurse shark's reputation as a maneater is undeserved as they cannot eat anything as large as a human and are placid sharks that will not bite defensively unless severely provoked.
- The grey nurse's name comes from its ability to "nurse" (or round up) small fishes into a tight school, for feeding.
The aquarium's oldest shark is Josephine, who is estimated to be 25 years old and has been at the aquarium for almost 20 years.
- In Australia in the '70s, grey nurse sharks were hunted almost to extinction due to fear of attack. The release of the movie Jaws in 1975 is thought to have had a huge influence on this. There are thought to be as few as 500-1000 left on the east coast of Australia.
- When the NSW government declared grey nurse sharks a protected species in 1984, they became the first protected sharks in the world.
- The freckles of a grey nurse shark are the equivalent of a human fingerprint, or the spots on a wobbegong shark.