The Grey Nurse shark (Carcharias taurus) is Critically Endangered on the east coast of Australia with a population of less than 1500 remaining. It is estimated they will be extinct within twenty to thirty years. This is largely due to significant hunting in the 1960’s and 70’s as they were seen as the bad shark and also by commercial and recreational fishing. Many are also still caught in the shark nets used to protect Queensland and NSW beaches.
Grey Nurse sharks practice an amazing method of reproduction which includes intra-uterine cannibalism until there is only one left in each side of the uterus. After a 12 month pregnancy two pups that are 1 to 1.2 metres in length are born. It is the ultimate survival of the fittest.
Grey nurse rescues
I have been fortunate enough to have been involved with some amazing rescues of Grey Nurse sharks at a place appropriately called Magic Point just south of the Sydney heads. This is a well-known juvenile aggregation site for these sharks.
The SEA LIFE Trust has provided some of the funding for these rescues.
The first occurred in February 20th 2014 with a shark with a noose around its neck. It was a juvenile female – the future breeding stock.
The divers carefully escorted the shark into a large plastic sock and it was then transferred to the surface via a stretcher.
There I removed a piece of bungee cord, administered an antibiotic and vitamin to assist with the recovery. The shark swam off strongly and has since recovered very well. It was seen in December 2015 near Coffs Harbour, some 500 kilometres north.
The second was also a female and had a hook stuck in the right side of its mouth. It was similarly caught but this time brought onto the boat and the hooks (yes there were two) removed. Again we have been fortunate to follow this shark’s progress due to the citizen science group Spot-a-Shark (see www.spotashark.com). This group photographs Grey Nurse sharks and IDs them by their spot patterns. This same shark was seen at the Tollgate Islands near Batemans’s Bay some 280 kilometres south also in December 2015.
This is an ongoing project as unfortunately there are often sharks with hooks and other fishing gear that need removal. The Manly SEA LIFE Sanctuary and SEA LIFE Sydney Aquarium have supplied the divers for these rescues and I thank them very much. It is an amazing opportunity to make a difference to the lives of these extraordinary sharks.
Article written by Dr Rob Jones of The Aquarium Vet