Number 1 Seabird Threat

Feral Herald |
One of the beneficiaries of eradication of invasive species on islands is Gould's petrel. Photo: Tony Morris (creative commons licence)
One of the beneficiaries of eradication of invasive species on islands is Gould’s petrel. Photo: Tony Morris (creative commons licence)

A new conservation issue emerged a couple of decades ago when Tasmanian wildlife officer Nigel Brothers showed that fishing operations were driving down albatross and petrel numbers by accidentally killing them as bycatch. The threat of long-line fishing caught public attention and led to reformed fishing practices, though seabird numbers continue to fall.[1]

An issue for seabirds globally with a much lower profile but even higher threat level is invasive species. A review of Birdlife International’s assessments of threatened birds published in Bird Conservation International in 2012 found that 75 percent of threatened seabird species are threatened or potentially threatened by invasive species compared to 41 percent threatened as bycatch and 40 per cent at risk from climate change plus severe weather.[2]

The invasive species causing problems on seabird breeding islands around the world include rodents, cats, pigs, goats, dogs, rabbits and cattle, all of which have been removed from some islands to improve seabird survival. By late 2006, rodents had been eradicated from 332 islands. Seabirds are especially vulnerable to predators on land because their extreme adaptations for life at sea render them clumsy on ground.

Subantarctic Macquarie Island was the Australian island with the best-known problems due to the combined impacts of cats, rabbits and rats. Endangered blue petrels were nesting only in small numbers on offshore stacks in the years before cats were eliminated. The problems were complicated by subantarctic skuas multiplying on a diet of rabbits and then becoming major predators of prions and other small petrels at their burrow mouths. Since a massive eradication program of cats, rabbits and rodents, vegetation has been recovering and seabirds returning to nest in growing numbers. Stephen Garnett says that ‘a suite of breeding seabirds once thought to be highly threatened in Australian territory has increased so much they can probably come off threatened species lists’.[3]

Skuas are predatory birds that can benefit from invasive rabbits or rodents, and the resulting build up in their numbers can then increase predation pressures on threatened seabirds. Photo: Su Yin Khoo (creative commons licence)
Skuas are predatory birds that can benefit from invasive rabbits or rodents, and the resulting build up in their numbers can then increase predation pressures
on threatened seabirds. Photo: Su Yin Khoo (creative commons licence)

Another conservation success due to an island eradication program is Gould’s petrel on NSW’s Cabbage Tree Island.[3] In 1989 it was the sole Australian breeding site with just 250 breeding pairs. Chicks were being killed by pied currawongs because rabbits had eaten out the understorey. Chicks were also becoming entangled in the sticky fruits of pisonia trees (Pisonia umbellifera). Since eradication of all three, and establishment of an additional breeding population on another island, numbers have climbed to over 1000 breeding pairs.

Another success was Lord Howe Island’s endemic woodhen, which has recovered from a population of just 10 pairs in the 1970s to 220 today due to the eradication of pigs and cats.[3] The New South Wales government is committed to eradicating rats from Lord Howe Island, and ISC is represented on the technical committee advising on the NSW Environmental Trust. Other Australian seabird islands facing predator problems include Norfolk Island, Christmas Island and Phillip Island.


[1] Some of this blog was previously published in Feral Herald in July 2012.

[2] Croxall J, et al. (2012) Seabird conservation status, threats and priority actions: a global assessment. Bird Conservation International 22: 1-34

[3] Garnett S. (2013) How birds are saved. Wildlife Australia 50(2): 30-32.

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Help protect NSW!

Our expert team has written a list of policy asks detailing exactly what the next NSW government needs to do to stamp out some of the worst invasive species impacts across the state. But they will only become a reality if every key political candidate at the 2023 NSW state election hears about it from you!

Dear National Deer Management Coordinator,

Please accept this as a submission to the National Feral Deer Action Plan.

[Your personalised message will appear here] 

I am very concerned about the spread of deer and am pleased that a national plan has finally been developed. Without urgent action, funding and commitment from all levels of government it is clear that feral deer will continue to spread and damage our environment.

The feral deer population in Australia is growing rapidly and spreading across the country, damaging our natural environment, causing havoc for farmers and foresters and threatening public safety. Unlike much of the world where deer are native, our plants and wildlife haven’t evolved to deal with these heavy hard hooved animals with a voracious appetite.
With no natural predators and an ability to adapt to almost all environments, they could occupy almost all of Australia unless stopped. Despite this, state and territory governments have been slow to respond and in Victoria and Tasmania they are still protected by law for the enjoyment of hunters.

This plan should be adopted by all governments but must also be underpinned by dedicated funding and clear responsibilities. A plan without funding or accountability is a plan that will fail and Australia cannot afford for this to fail.

In order to prevent the spread of feral deer and reduce their impact on our native wildlife, ecosystems and agriculture, I ask that the following recommendations be adopted for the final National Feral Deer Action Plan:

1. All federal, state and territory governments should adopt the National Feral Deer Action Plan and declare feral deer to be a priority pest animal species.

2. All federal, state and territory governments should commit to:

  • Contain deer to the existing large population areas.
  • Reduce and eradicate smaller and isolated populations.
  • Protect important environmental assets such as world and national heritage areas.
  • Develop and fund regional plans and strategies to manage deer populations which involve land managers across all tenures.

3. In order to drive action and the success of this plan, there should be dedicated Commonwealth funding and support for:

  • A permanent national feral deer coordinator position.
  • A permanent federal feral deer action committee with representatives from the commonwealth and state and territory governments and the environmental and agricultural sectors.
  • An ongoing public education campaign on feral deer.
  • A network of regional feral deer coordinators to drive local action across tenures.

4. The expected outcomes for the plan need to be more ambitious, with clear interim targets including:

  • Within one year, all States and Territories should have in place arrangements to implement the National Feral Deer Action Plan, including allocating dedicated funding for implementation.
  • Within one year, feral deer management plans should be developed for key environmental assets of national significance, including the Tasmanian Wilderness World Heritage Area, the Greater Blue Mountains, the Australian Alps, the Gondwana Rainforests and the Wet Tropics of Queensland.
  • Within five years coordinated landscape scale management should be in place where land owners, land managers, government and community are demonstrably working together.

5. A national feral deer containment map with three zones should be adopted. It should be more ambitious than the zone map in the current draft plan and there should be greater clarity in the naming of the zones. Improvements that should be adopted include:

  • Renaming the zones to better reflect the management intention to ‘Containment Zone 1’ (the current large population zone), ‘Containment Buffer Zone 2’ (the current buffer zone) and ‘Eradication and prevention Zone 3’ (the current small isolated population zone).
  • The NSW northern rivers area should be in the eradication and prevention zone as there are few feral deer currently in this region and eradicating isolated populations and preventing spread into this area is still possible.
  • The whole of South Australia should be in the eradication and prevention zone as eradication is the goal of the SA Government.
  • The Tasmanian region in the containment zone should be smaller to reflect greater ambition and potential for eradication of deer populations.
  • In eastern Victoria areas such as Wilson’s Promontory, Westernport islands and the Mornington Peninsula should be in the eradication and prevention zone.

6. There should be consistent laws and regulations across all states and territories that:

  • Recognise feral deer as a pest animal and treat them as such.
  • Establish a clear responsibility for all landholders and managers to be involved in feral deer control programs.
  • Set clear penalties to stop the wilful or negligent release of feral deer.
  • Prevent new deer farms in areas where no feral deer are present and phase out all deer farms in the eradication and prevention zone.
  • Enable enforcement of compliance, including on government land.

I support the follow principles being adopted in the final National Feral Deer Action Plan:

  • Feral deer are a pest and should be treated as such on all tenures, except on approved deer farms.
  • Federal, state and territory governments have a responsibility to fund the outcomes under this plan.
  • All land managers in areas where feral deer are present have a responsibility to be involved in feral deer control programs.
  • The focus of management efforts should be on eradication of isolated, satellite populations, protection of key environmental assets currently impacted and stopping the spread to new regions.
  • Feral deer control should be undertaken humanely, safely and professionally according to agreed protocols and all tools which meet this criteria should be adopted, including aerial control.
  • Funding for coordination, regional planning and community engagement is necessary for effective feral deer management.
  • Ongoing management and follow up control efforts are required to achieve long lasting results.
  • Rules and regulations should be consistent across jurisdictions and land tenures.
  • Recreational hunting is not an effective strategy for feral deer control and should not be relied upon.
[Your name]
[Your email address]
[Your suburb], [Your state]