Hunting and aerial baiting videos
Click on the images below to see videos of the eradication work that has been carried out on Macquarie Island.
Hunting on Macquarie Island video
|Aerial baiting on Macquarie Island video
Pest Eradication Principles
Eradication of a species from an area is distinct from control. It requires 100 per cent removal of a pest species from the target area, otherwise it cannot be deemed successful.
Unlike control methods which are intended to be ongoing and seek to reduce a population but without attempting to remove all individuals, eradication is intended as a once-off operation to remove all individuals, and gain a cessation of the impacts caused by invasive species.
Almost all forms of pest control or eradication become more difficult with successive attempts (this is for a variety of reasons). This is true for both the methods that were employed in the Macquarie Island eradication project – poison baiting and hunting. When targeting pest populations it is important that the first attempt is the best possible one.
As a result it is vital that eradication projects are meticulously planned.
Eradication projects also need perseverance. The last individual animals are usually the most difficult to get, and the most expensive and time consuming. This can be dispiriting, but it is an inevitable and critical part of an eradication project.
Finally, having achieved eradication from a target area, robust biosecurity measures need to be in place to ensure that the risk of reinvasion is extremely low. A few stray rodents reaching an island in the future could undo all the work and cost of eradicating them.
During the planning phase, the project employed four staff; the project manager, assistant project manager, project officer and administration officer.
About 30 staff were employed in the peak activity of aerial baiting, including helicopter pilots and ground support staff, field assistants, and other specialist roles such as GIS support. About 12 hunters and dog handlers were recruited annually for three years of follow-up rabbit hunting and monitoring operations.
Helicopters were the vital platform for the first stage of the eradication project – the aerial baiting, that was completed in 2011. Their manoeuvrability and ability to hover, together with the ability to spread bait evenly from under-slung buckets, made them the only choice to deliver the accurate baiting required on Macquarie Island.
Despite the weather conditions, winter was chosen as the preferred time for baiting, as this is when most of the wildlife are absent from the island and pest populations are at the lowest point in their annual cycle.
All transport of materials and staff to and from the island is by ship. The P&O icebreaker RV Aurora Australis was chartered for all voyages in support of the eradication project..
The bait is comprised of pellets of coarsely ground grain, a lure to attract animals, and a small amount of wax to repel water. The bait contains the toxin brodifacoum; an anti-coagulant often used in domestic rat poison. The concentration of the toxin is 20 parts per million (ppm). This is less concentrated than commercially available bait for domestic use such as Talon, which contains 50ppm of the same toxin.
The project used approximately 300 tonnes of bait. The bait was chosen for its successful track record in island eradication projects in New Zealand, Australia and the Pacific and because it performed well in the initial bait trials on Macquarie Island.
There are no roads on Macquarie Island. Getting around the island involves walking. Ten field huts, strategically located around the island, provided hunters and dog handlers with bases from which to conduct hunting operations. Five of these huts were installed by eradication project staff and three have since been removed. One will be left for other work purposes on the west coast and the other will be removed.
Dogs were used to detect rabbits and rodents on the island. An important part of their training was to teach the dogs not to disturb native animals. The young springer spaniel pictured is beginning to learn this with chickens. Dogs undertook a two-stage assessment and certification process to ensure that dogs were focused on rabbits and averse to native species. The 11 rabbit detection dogs, mostly springer spaniels and Labrador retrievers, went to the island in April 2011.
Rodent detecting dogs joined the project in 2013 and spent 12 months on the island. Winter 2013 marked two years since the completion of aerial baiting and the task of rodent dogs was to scour the island to determine whether rodents had been successfully eradicated. Following a year on the island, the rodent dogs were removed together with the rabbit dogs and the hunting team in April 2014.
| Macquarie Island discovered by sealing brig, Perseverance
| Island seals exploited for skins
| prior 1820
| Cats established on Macquarie Island
||Oiling industry established based on elephant seals and penguins
|| Rabbits and weka introduced by sealers to Macquarie Island
| Early 20th C
|| Rats and mice recorded as established on the island (likely to have been much earlier)
| 1911 - 1914
|| Mawson established a research station on the island
|| Cessation of penguin and seal exploitation industry on island
|| Macquarie Island established as a wildlife sanctuary
|The Australian Government established the Australian National Antarctic Research Expeditions station on island
|| Rabbit damage to vegetation record by botanists
||Poisoning trials conducted to assess viability for rabbit control. Myxoma virus introduced unsuccessfully.
||Rabbit fleas introducted to provide a vector for eventual release of myxoma virus to control rabbit numbers. Flea releases continued for the following decade.
| The Tasmanian Government Parks and Wildlife Service commenced an active role in management of the island
| 1978 - 79
||Rabbit population reached an estimated 150,000
| 1980s - 90s
||Rabbit population reduced to about 10% of late 1970s levels through ongoing myxomatosis release program
||Cat control program escalated
| 1998 - 2000
||Intensive cat eradication program resulted in last cat being destroyed in June 2000
| 1999 - 2003
||Rabbit population observed to be growing. Reduced effectiveness of myxomatosis evident.
Production of virus ceases 1999.
| 2004 - 05
||In response to increasing rabbit numbers and rodent impacts on burrowing seabirds a Natural Heritage Trust funded project produced a draft eradication plan for these species
||The 2006 Macquarie Island Nature Reserve and World Heritage Area Management Plan is finalised including recommendation to undertake an eradication program for rabbits, mice and rats.
||The Tasmanian and Australian Governments announced a joint commitment to fund a $24.7 million eradication project – the largest of its kind in the world to date for these three species
| 2007 - 10
||Key staff are employed and commence planning for the eradication project. All necessary environmental impact assessments, operational plans, regulatory processes (including quarantine, bait approvals, shipping, aviation, occupational health and safety and other assessments and approvals) are prepared. Five new huts are installed to support hunting operations.
|Aerial baiting begins on Macquarie Island after the team arrives a month late due to shipping delays. Adverse weather conditions limit helicopter operations and decision is taken to cease further baiting and withdraw the team in late July.
||Baiting team arrives on Macquarie Island in April. Aerial baiting completed in July. Hunters and dog handlers arrive in late July to begin hunting of surviving rabbits. Thirteen rabbits killed in hunting operation. No further rabbits killed since November 2011. Hunting continued during 2012.
||Rabbit hunting continues. Rodent detection dogs deployed to the island for 12 months to determine the presence or absence of rats and mice.
||Project declared successful in April 2014 upon return of team from Macquarie Island to Hobart.
The Eradication Plan and Associated Documents