The Grey Nurse Shark

A story of ‘Not to judge a book by its Cover’

Just a little warning, this story is based on the reasons why in particular the east coast population of the Grey Nurse shark is critically endangered.

Previously we talked about the facts of what the shark is, where it is and where it goes during migration. Also, why you can find them in aquariums around the world and their favourite habitats. Worldwide, these sharks are classified as vulnerable; however in Australia’s east coast they are listed as critically endangered as there are fewer than 1500 individuals left.

Lets start with the history of them before the Conservation Protection in 1984. Side note, you maybe wondering why I used the quote ‘not to judge a book by its cover’. Well, when you see a Grey Nurse Shark in the wild or in a aquarium you first notice is teeth. The fearsome appearance of the shark did scare people during a time when the public perception of a shark was a mindless killing machine. 

This led to a time when killing any shark for the sake of protecting beaches, to put minds at ease, this was the thing to do back then and the first response after a shark attack happened. Yes; some sharks are dangerous to us if we provoke them or a case of being mistaken for prey and the Grey Nurse shark  was one of the sharks that is relatively placid. Still its appearance is what fuelled human misrepresentation of what the Grey Nurse was and began years of senseless killings. This happened between the 1950′s to the 1970′s, so two decades of nearly hunting them out to extinction.

During that time the invention of a underwater firearm known as a ‘Powerhead’ was used to kill sharks (Powerheads used rifle or handgun ammunition in a tube like device and fires when you poke the shark with force, it activates the firing pin and bang, the shark is dead). Many divers who hunted these sharks used these aquatic firearms. The mentality during that time was ‘A good shark is a dead Shark’.

This hit the East Coast Population hard as these sharks have a slow reproduction recovery as it takes them 6 - 8 years to hit sexual maturity and they pup every second year to 1 - 2 juvenile Grey Nurse sharks. So repopulation is the next biggest challenge as Grey Nurse Shark from the east coast never migrate outside of the east coast of Australia.

Now we are in a time where we learnt that sharks are important to the ocean’s eco-system. Still, the Grey Nurse sharks still has threats from fisherman land base fishing and boat fishing in areas known as nursing grounds (Bryon Bay, Magic Point etc.). Recently a dive team from Sea World did a dive operation at Bryon Bay, NSW, Australia to remove a fishing hook of a Grey Nurse sharks as discarded fishing tackle is one of the many threats to these sharks. Hooks in particular are responsible for 70 percent of Grey Nurse Shark deaths.

The Australian Government researched and concluded that the East Coast Grey Nurse shark needs to be at 5000 individuals for the species to survive long term, so each of the 1500 individual sharks are important right now for the survival of these important sharks.

Now its 2018 and still these sharks are not out of the woods and its up to us to support conservation efforts to protect and for the population to grow to that vital number, otherwise they will be gone from the east coast for good and the efforts would have been for nothing.

Grey Nurse Shark (Carcharias taurus)

Grey Nurse, Sand Tiger or Spotted Ragged Tooth Shark, these sharks are the most popular elasmobranchs in the Aquarium World.

These sharks can be found in both the east and west coasts of Australia (as they are rare in the Northern Territory and Tasmania), the eastern seaboard of the USA and all the coastline of South Africa. The Grey Nurse shark was the first elasmobranch species to receive protection status when the New South Wales Government implement it in 1984.

Despite their fearsome appearance, these sharks are relatively placid in terms of behaviour making them the top shark to have in Aquaria.

They’re known to grow to a length of 318cm and have a annual migration in each country they're known to be at. The migration range is known to be more than 1000km. During this migration, the adults swim north to feed and mate before returning southward to pup in area known as nursing grounds.

Their favourite habitat are caves, overhangs and reefs shallower than 20 metres, they favour both temperate and tropical waters. On the ICUN Red list, they are classified as vulnerable globally; however on Australia’s East Coast they are listed as critically endangered as there are fewer than 1500 individuals.