Lord Howe Island – protecting paradise

Feral Herald |

By Warwick Sprawson

The World Heritage listed Lord Howe Island is staggeringly beautiful. Evolving in isolation 600 kilometres off the east coast of Australia, its precipitous mountains, golden beaches and dense subtropical forests are home to hundreds of species of plants, insects and animals found nowhere else on Earth.

But behind the postcard idyll a battle is being fought. Around 1850 mice were inadvertently introduced to the island. Rats came in 1918, escaping a sinking ship. The rodent population boomed as they ate the island’s insects and seedlings, destroyed bird eggs and devastated crops, leading to the extinction of five bird and 13 invertebrate species, and threatening another 70.

In 2019 – after 20 years of studies, trials, planning and community engagement – a six month program of baiting, dog detection and monitoring was launched to eliminate rodents from the island. Led by the Lord Howe Island Board, the Rodent Eradication Project was supported by numerous partners, including the Invasive Species Council.

After an intensive effort, in October 2019 the last of an estimated 150,000 rats and 210,000 mice was eliminated from the island.

Darcelle Matassoni, Lord Howe Island Board’s 2021 Rodent Response Manager from April to August and Assistant Project Manager – Community during the latter stages of the eradication project, remembers feeling cautiously optimistic.

“We didn’t know for sure it was the last rat,” she says. “We needed more monitoring to be confident. But we were hopeful.”

Black winged petrels just are one of many native species bouncing back as a result of the rodent eradication project. Photo: Nicholas Carlile

As rodent monitoring continued, the project’s benefits were slowly revealed. The breeding success of the black-winged petrel increased from 2.5 per cent to more than 50 per cent. Numbers of the Lord Howe Island woodhen – a flightless bantam-sized bird – have more than doubled. Populations of the island’s many endemic species of land snail began to recover, including two critically endangered species. Plant species recovered too, with more seeds and seedlings, including those of the critically endangered little mountain palm.

The price of freedom (from rodents) is eternal vigilance. Since October 2019 there have been more than 80 reported rodent sightings, each one carefully followed up with no positive rodent signs confirmed.

So when a community member reported seeing two rats on 14 April 2021, the Lord Howe Island Biosecurity team followed their standard procedure for a reported sighting.

“Our biosecurity detection dog handlers went out to the area,” recalls Ms Matassoni, “but this time Zuma, our biosecurity detection dog, had a strong indication and went directly to a particular tree. The handler found a rat nest in the tree, still warm, then sighted a rat’s tail.”

After 18 months with no positive rodent signs, it was a momentous discovery.

Response team kicks into action

With confirmation rats were on the island, the team immediately launched the rodent response plan they had prepared for just this eventually. Supported by members of the NSW National Parks and Wildlife Service, the response team quickly deployed five detection dogs, 1493 bait stations, 1300 monitoring devices and 125 trail cameras to fight the outbreak.

“At that stage we didn’t know if it was just two rats or a lot more,” says Ms Matassoni, “so we planned for both the best and worst-case scenarios.

“After those first two rats it was a full eight days before we detected another rodent. The main cluster ended up being just a few hundred metres from where the original rats were detected. It shows just how hard they are to detect when they are in such low numbers.”

Highly-trained conservation detection dogs have played a critical role in the fight to keep rats from Lord Howe Island. Photo: Justin Gilligan

Genetic testing is currently underway to determine if the rats are survivors from the island’s initial rodent population or have been inadvertently reintroduced from the mainland.

To date 96 rats have been eliminated, with no sign of rodents detected since 28 July. Intensive monitoring will continue until the end of the year, to provide further confidence in the outcome of the response effort.

For Ms Matassoni the outbreak was yet another lesson in the battle to control invasive species.

“It emphasises the importance of ongoing biosecurity, in preventing other invasive species from establishing on the island.”

She smiles.

“After all, it’s an amazing privilege to play a part in protecting Lord Howe Island’s natural environment and saving species from extinction.”

Masked boobys breed on Lord Howe Island, and outer islands. Photo: Jack Shick | www.lordhoweislandtours.net

A watchful, hopeful eye

We’re keeping a hopeful eye on the Lord Howe Island situation. Normally the success of an island eradication requires no rodent sightings for a full two years of intensive monitoring.

The April 2021 outbreak now resets the clock on the official declaration of eradication. It also highlights just how vital island biosecurity is in the fight to keep rodent hitchhikers and other unwanted pests from arriving via regular cargo ships from Port Macquarie and elsewhere or in the luggage of arriving air travellers.

After the recent outbreak, biosecurity surveillance and animal control measures have already been upgraded.

If eradication is declared and the island’s rodent free status can be maintained, Lord Howe Island will be the world’s largest inhabited island that can boast it successfully eradicated rats. It will begin an exciting pathway to ecological recovery and inspire similar efforts in other island communities.

You can help support our work to accelerate island eradication efforts across Australia by donating today.

Banner image: Franz Zenhaus | Flickr | CC BY-ND 2.0

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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]
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