Most of Lord Howe Island closed to visitors after outbreak of plant fungus

The majority of Lord Howe Island has been closed to nonessential visitors due to an outbreak of myrtle rust, a highly infectious plant fungus.

Lord Howe’s permanent park preserve, which covers about 70% of the world heritage–listed island, was “temporarily closed to all nonessential visitors, effective immediately”, the Lord Howe Island Board said.

Myrtle rust was discovered on the island on 3 February. Despite ongoing treatment and preventative fungicide spraying, weekly sweeps had identified three additional infected sites, two of which were around 230m from the boundary of the permanent park preserve, the board said.

Myrtle rust affects plants of the Myrtaceae family, which includes eucalypts, paperbarks and tea trees. The fungus affects flower buds and new growth, affecting the ability of plants to photosynthesise.

There is concern myrtle rust may affect Myrtaceae species endemic to the island, including the mountain rose (Metrosideros nervulosa), the scalybark (Syzygium fullagarii) and the Gnarled Mossy cloud forest, a critically endangered forest which crowns Mount Gower, the island’s highest mountain.

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The fungus produces thousands of spores – which remain viable for up to three months – that are readily spread by wind, rain and on clothing, skin, hair, footwear and equipment.

“Due to the escalating risk, closure of the permanent park preserve is being implemented to prevent spread by human activity,” the board said. “The rust has the potential to change the way our mountains and forest look, it may alter food webs and ecology, and potentially affect world heritage values.”

Authorities held an information session on Thursday evening at the island’s community hall, with experts from the NSW Department of Planning and Environment, and the Department of Primary Industries.

The board has not given a timeline for when the preserve will reopen, noting “the closure will be in place until there is confidence that the necessary hygiene practices can be implemented consistently and effectively … and support a managed level of visitation”.

Prof Robert Park, director of the Australian cereal rust control program at the University of Sydney, said myrtle rust was first detected in Australia in 2010 on the NSW Central Coast.

“Rusts are among the most feared of all plant pathogens – they spread rapidly over thousands of kilometres on wind currents and can cause huge losses in plant production,” Park said.

“Myrtle rust rapidly invaded the entire east coast of Australia and has caused the near extinction of at least three rainforest species. It was detected at Lord Howe Island in 2016, and eradicated, but has now managed to spread there once again. This second incursion clearly illustrates how incredibly difficult rust diseases are to manage once they are introduced into a new region.”

Operators on the island are keen to emphasise that while the preserve is shut, other activities are still open to tourists.

“We are still open for business except for certain activities,” said Stephen Sia, treasurer of the Lord Howe Island Tourism Association. “There are still plenty of places that visitors can visit … The settlement area in itself is quite nice to walk around, and all the [11] beaches are open, and people can still swim.”

Sarah Shields, media manager for Capella Lodge, said: “The walks in the parks are a big part of the island’s activities on offer but at this time of year … you would be spending a lot more time in the water.

“March is a really peak time for Lord Howe Island in terms of its marine activities.

“The priority for the island at the moment is to stop the spread of myrtle rust everywhere … We support what [the island board] are doing [but] we would like also for the board to find a way in which the businesses can also coexist while the board is dealing with this matter.

“It’s almost like Covid revisiting the island again – exactly three years ago we shut down the island.”

The permanent park preserve, which also covers Ball’s Pyramid and islands neighbouring Lord Howe, was established in 1982 to protect the region’s biodiversity. It is home to 241 native plant species, of which more than 100 are only found on the island.

The Lord Howe Island Board was contacted for comment.