Are shark culling drumlines doing more harm than good?
Series: Shark Culling Drumlines (Part 2)
Despite shark populations plummeting globally, including in Australian waters, despite taxpayers' money needed more than ever as we recover from the COVID pandemic, and despite Australia committing to protect vulnerable species, shark culling drumlines are being used increasingly by Queensland (QLD) and New South Wales (NSW) governments.
There are two types of drumlines in use in Australia today. One is the traditional drumline (pictured below), and the other is the Shark-Management-Alert-In-Real-Time drumline, also known as a catch-alert drumline (pictured below). These drumlines raise concerns because baited drumlines attract sharks close to shore, compromise public safety, and serve no proven purpose other than culling sharks.
Both drumline designs consist of a drumline buoy, a baited hook, chain and an anchor. The fishing hooks are about as long as your arm and baited with fish like mackerel and shark meat. A drumline aims to lure sharks in, so they take the bait and get stuck on the line. Once caught on the hooks, the distressed sharks become bait for larger sharks. Other marine animals also get caught on drumlines.
Essentially, a drumline is a floating trap anchored to the sea bed used to lure and capture large sharks using baited hooks, attracting sharks close to shore, compromising public safety.
In 2019, the QLD government tendered (#DAF19031) for 383 traditional drumlines to be placed by contractors at approximately 86 locations, including locations in supposed marine parks such as the Great Barrier Reef.
In QLD, the contractors check these traditional drumlines every 21 days, meaning any sharks caught on drumlines are predominantly dead when removed. This activity is a culling measure designed to catch and kill sharks, targeting 19 species, including great white sharks, bull sharks, tiger sharks, and others, in the name of public safety. Many other shark species and marine life are killed, including turtles, dolphins and rays.
These drumlines were first used in 1962 and have been placed in more and more locations since then across QLD. Since 1962, there has been a 92% decline in great white sharks and hammerheads based on data collected by the QLD government's own shark culling devices.
New South Wales
Over 300 catch-alert drumlines are in place in NSW between Bega and Tweed. They are similar in design to the traditional drumlines, except they have a GPS alert tracker installed to notify authorities when an animal gets caught on the hook. When an alert is triggered, the NSW catch-alert drumlines are responded to within 30 minutes for the shark or marine animals to be tagged and released, though delays can occur.
The catch-alert drumlines are set every morning (weather dependent) offshore at a depth between 8-15 metres of water. They are collected at the end of each day and are not left overnight. The government stated that these drumlines would be placed approximately 500 metres from the shore. However, following the shark incident at Little Bay in Sydney, on 16 February 2022, additional catch-alert drumlines have been placed in locations frequently used by swimmers and spearfishers, such as South Bondi and located only about 50 metres from shore.
So, are drumlines effective?
Traditional drumlines are undoubtedly effective at catching and killing; however, they do this indiscriminately, and 97% of dead sharks on QLD drumlines are considered at-risk species. In the Great Barrier Reef alone, 80% of sharks caught on these drumlines were found dead. The following sharks found alive, regardless of whether they are protected or endangered, are euthanised:
great white sharks
hammerhead sharks (all species),
Catch-alert drumlines predominantly catch target sharks, particularly great white sharks, representing 44% of all sharks caught. Overall, catch-alert drumlines present a 3% fatality rate (over 1 in 5 blacktip sharks and smooth hammerheads representing the greatest number killed). However, the catch-alert drumlines are much better at minimising the impact on wildlife than the traditional drumlines, although there are still concerns about the long term impact and survival rate of the animals caught.
Significant injuries to sharks due to large fishing hooks, such as the hooks on a drumline are sadly common. Whilst sharks are sometimes released alive and uninjured from drumlines; they do not always survive. Sharks released with a significant injury will slowly starve to death if they cannot hunt or eat and, in a weakened condition, become potential prey for other animals.
The case of the great white shark
Ironically, the great white shark is a target of traditional and catch-alert drumlines. It's ironic because the great white shark is listed as vulnerable under the Australian Environment Protection and Biodiversity Conservation Act 1999 and is also listed as endangered internationally by several mechanisms. For example, the great white shark (scientific name Carcharodon Carcharias) is listed in Appendix II of the Convention on International Trade in Endangered Species of Fauna and Flora (CITES) and also on Appendices I and II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS).
In addition, the NSW Shark Meshing (Bather Protection) Program (SMP) 2020/21 Annual Performance Report states that:
"Traditional shark bite mitigation programs such as the SMP invariably affect non-target species, and the SMP is listed as a key threatening process."
By the NSW government's admission, traditional shark nets and drumlines significantly threaten to negatively impact already threatened species, such as the targeted white shark and non-target species such as marine reptiles and mammals, to name a few. Furthermore, the threat from these outdated devices is so significant that the government has reported that they can cause non-threatened species to become threatened.
The Australian Government Department of Agriculture, Water and the Environment states that:
"Great White Sharks are particularly vulnerable to non-natural sources of mortality as they have late reproductive maturity (10 years for males and 18 years for females), long gestation periods (exceeding 12 months) and produce only 2-10 pups every 2-3 years."
Contrary to common public belief, great white sharks are not increasing in numbers or 'swarming' our oceans. For example, approximately 200 tagged great white sharks were seen across NSW in the entire year of 2020, but only 300 individuals since 2015.
Shark populations continue to plummet worldwide
An estimated 100 million sharks are killed annually by commercial fishing, discarded as bycatch or other destructive fishing practices. As a result, almost all shark populations worldwide have plummeted, and according to the IUCN Red List, a third of shark species are vulnerable to extinction. Globally shark populations have declined by 70% in the last 50 years.
Catch-alert drumlines have a reduced shark fatality rate. However, little information exists on the long term health of sharks that are caught and then released.
In one year alone, between September 2020 and August 2021, the catch-alert drumlines around Byron Bay caught 103 great white sharks on separate occasions meaning each shark has probably been caught more than once in those 12 months. So how can we be sure the stress and injury this causes to the shark do not cause long term health issues for the shark?
Aside from the costs of maintaining shark culling programs in NSW and QLD, the impact of these programs on vulnerable species and the marine environment, and the irony of catching and killing the same species Australia commits to protect; the other concern is the level of swimmer safety provided by these programs.
Does stringing up a curtain of baited hooks up and down our metropolitan beaches, attracting more sharks, sound safe?
And why do the QLD and NSW governments continue using drumlines that harm animals and the marine environment despite the availability of modern technologies such as drones, eco shark barriers and other modern solutions?
Drumlines catch sharks and other marine creatures that thrash around at the end of hooks and essentially become bait, attracting more and more animals into the area, including larger sharks. The close proximity of drumlines to beaches and, therefore, swimmers is a significant concern. It's yet another device providing beachgoers with a false sense of security.
Drone technology is preferred to drumlines (and shark nets) and can be used to spot a shark in waist-deep water no matter the visibility. In addition, the scientific evidence supports that drones effectively keep beachgoers safer.
Now is the time to end shark culling in Australia!
Complete the NSW Department of Primary Industry's Shark Management Survey 2022 that closes on 16 June 2022 or go to our Act Now page for other ways you can speak up about the outdated shark control programs in NSW and QLD.
Your opinion counts.
References, links and further reading
Australia's Shark Cull Exposed - Tiger Shark hooked through its head and killed by Queensland Gov!, YouTube, Envoy Foundation.
Heartbreaking Footage of Juvenile Dolphin Caught on Drumlines in Australia, Gold Coast, 2014, YouTube Sea Shepherd.
Cavanagh, R. D., Kyne, P. M., Fowler, S. L., Musick, J. A. and Bennett, M. B. (eds) (2003).
The Conservation Status of Australasian Chondrichthyans: Report of the IUCN Shark Specialist Group Australia and Oceania Regional Red List Workshop, Queensland, Australia, 7-9 March 2003. The University of Queensland, Brisbane.
CITES, Convention on International Trade in Endangered Species of Fauna and Flora, Other shark species included in the CITES Appendices, Appendix II.
CMS, Convention on the Conservation of Migratory Species of Wild Animals, Appendix I and Appendix II.
Current Program - SharkSmart, NSW Department of Primary Industries.
Death or injury to marine species following capture in beach meshing (nets) and drum lines used in Shark Control Programs - Department of Agriculture, Water and the Environment, Australian Government.
Roff, G., Brown C. J., Priest, M. A. & Mumby, P. J. 2018. Decline of coastal apex shark populations over the past half century. Communications Biology, 1, 223.
Shark Control Program Bait, QTenders, Tender Reference DAF1903, Tender Overview, Section 1, Queensland Government, 2019.
Shark populations on the Australian East Coast - what are they doing and how do we know?, article by Envoy: Shark Cull documentary.
World's largest shark management program deployed to NSW beaches, NSW Government, Media Release, 19 September 2021.