Historically the Grey Nurse Shark was mistaken for a man-eater, but we now know this is not the case despite it's large, powerful and toothy appearance. They in fact feed on fish, squid and crustacea and pose no threat to swimmers, surfers or divers. Grey Nurse Sharks tend to gather in groups at specific locations known as ‘aggregation sites’ and favour rocky gutters, cave entrances and overhangs
Commercial fishing of the Grey Nurse began in Australia in the 1850s. They were initially harvested due to their liver oil being ‘of excellent quality for burning in lamps’ and their skin producing the best quality shark leather. Additional threats came later, such as game fishing, bather protection nets and even groups of skin divers and SCUBA divers with spears and explosive powerheads helping to decimate the population. Due to their placid nature, Grey Nurse sharks were easy targets. Their slow growth, late onset of sexual maturity and low numbers of offspring do not lend the Grey Nurse shark populations to bounce back easily in the face of adversity. Thus by the late 1970s the Australian east-coast population had declined so much it was listed as ‘critically endangered’ and in 1984 it became the world’s first protected shark under New South Wales legislation.
The Grey Nurse is slow to recover and remains critically endangered. Although ‘protected’, inevitably they still become entangled in nets, litter or fishing gear, and become victims of by-catch. In most aggregation sites no baited hooks are allowed within a 200m radius, but line-fishing with lures is allowed. It is still very common to see sharks snared on fish-hooks when diving in aggregation areas – obviously the sharks don’t know the boundaries of the ‘protected’ area but you could also question how stringently the fishing regulations are adhered to.
On the positive side, many aggregation sites are now popular attractions for divers who visit to admire and photograph the sharks rather than kill them. The fact that people will pay for trips to see wild Grey Nurse should give more incentive to protect them – people want to see healthy sharks, not watch them dying from injuries. More and more people who are lucky enough to encounter Grey Nurse Sharks are becoming advocates for the species and there are now even trained groups dedicated enough to remove hooks and tackle from injured sharks. Dive communities such as ‘spot a shark’ and ‘reef check’ are building libraries of ID pictures to track and learn more about the sharks behaviour so we can help to protect them.
What can you do to help?
Support the establishment of a proper Sydney Marine Parkhttp://www.sydneymarinepark.org.au/
Don’t fish in known aggregation sites e.g. Magic Point (Maroubra).
Pick up any discarded fishing tackle or marine debris you find on a dive.
Take photos of sharks and donate them to research programmes e.g. http://www.reefcheckaustralia.org/grey-nurse-shark-watch.html