Drumlining is a technique employed by the Western Australian Government to control the shark population.
By Olivia Shiels
In January this year the Western Australian Government commenced a shark culling program in response to seven fatal shark attacks in the state over the last three years.
The plan involves setting baited hooks known as “drum lines” about one kilometre off shore in various locations around Perth and the South-West.
The project is targeting great white, tiger and bull sharks over three meters in length. Targeted sharks found on the hooks are shot and disposed of by contracted fisherman.
While this method is simple in theory, practically there are many complications to overcome. The current figures suggest the program has not been successful in reaching their targets.
Of the 66 sharks caught on the hooks so far, 49 were below the three-meter requirement.
Sharks drown on hooks
By the time sharks are found on the hooks they have often succumbed to their injuries or are so badly wounded they die soon after being released.
Sharks need to swim in order to breathe, so once they are hooked they will often drown due to a lack of oxygen.
Moreover, while the “kill zones” are patrolled 24 hours a day, the sharks may struggle on the hooks for over 12 hours before being found by a contractor.
The hooks used on the drum lines are intended to cause serious damage to any creature that is caught.
Sea Shepherd Australia reported to Perth Now of the gruesome and inhumane suffering of sharks that become hooked on the drum lines. “We have seen lots of sharks with hooks in their heads being cut out and thrown back into the ocean- they are not going to survive or are wounded to the point where they cannot eat”.
95% of sharks caught have been tiger sharks
63 of the 66 sharks that have been caught so far have been tiger sharks. Tiger sharks are rarely known to attack and it show little aggression towards humans.
No great white’s have been caught, despite being the target species responsible for the most attacks on humans.
What are the alternatives?
Alternatives to shark culling are in place around the world and are constantly developing. Shark “spotters” patrol beaches in Cape Town, South Africa to prevent sharks swimming close to shore. The program has so far been successful in reducing the rate of attacks.
In Brazil, sharks spotted close to popular swimming beaches are captured, tagged and released eight kilometers off shore.
This program has reduced shark incidents in Brazil by 97 per cent, without killing any animals in the process.
In contrast, a culling program in Hawaii that saw over 4,500 sharks killed between 1959 and 1976 resulted in no significant decrease in shark bites, strongly suggesting the culling method is ineffective.
Tagging program helps reveal important information about sharks
The Department of Fisheries in Western Australia currently have a tagging program in place that collects vital information about shark migration patterns that can assist in predicting their movements along the coast.
This information can in turn help protect beach goers. However, the culling program means tagged sharks are being captured and killed and therefore this valuable information is lost.
Scientific information about the movements of the endangered great white shark has been gathered via the acoustic transmitters applied in the tagging program.
Research has revealed great whites have been known to travel between South Africa and Australia.
Important knowledge on where great whites nurse and feed can also be gained through the tracking devices.
The future of drum lining
Western Australia’s Environmental Protection Authority will assess the Government’s request to extend the shark culling program for three years
The EPA will assess the government’s proposal to extend the drum lining program until April 2017, after which the program will be reviewed.
The Federal Government will also be involved in assessing the extension of the program, after initially choosing not to analyze the environmental impact of the culling on endangered species.
The extension would see a 22-week program take place over three years.
The EPA will publish their recommendations in regards to the future of the program later this year.