Threatened species on Lord Howe Island are making a striking comeback after the introduction of a rodent eradication program several years ago.
Key points:
- The Lord Howe Island woodhen’s population has doubled in the past year
- The numbers of more than 30 other threatened plant and animal species found on the island are also recovering
- Extensive monitoring will continue, with a focus on strong biosecurity controls
Among the species flourishing on the World Heritage-listed isle, which sits about 600 kilometres east of Port Macquarie on NSW’s Mid North Coast, is the Lord Howe Island woodhen.
It’s a flightless bird, endemic to the island, and the most recent woodhen census revealed its numbers had more than doubled in the past 12 months.
Atticus Fleming, the chairman of the Lord Howe Island Board and head of the NSW National Parks and Wildlife Service, said the woodhen was once on the brink of extinction.
“The Lord Howe Island woodhen is probably the most famous of all the species on Lord Howe — it’s an emblem for the island, and the population has increased to over 1,100 birds in the latest survey,” he said.
“That is an incredible return of that species when you think, going back to the 1970s, there were only 30 birds.
“And going back four years, before the rodent control program, there were only 250 birds.
“So the population has increased four or five-fold since we’ve undertaken the rodent control program which is just an incredible result … the population has basically doubled in the past 12 months.”
‘It shows species can rebound’
Lord Howe Island was the focus of a large-scale, state government-led rodent control program in 2019.
Before the program, the island was being heavily impacted by thousands of rodents, which were damaging plants and animals.
Now, with rodents removed, more than 30 threatened plant and animal species found on the island are recovering.
Other bird species thriving include the black-winged petrel, masked booby and Lord Howe currawong.
“The masked booby is breeding on the main island for the first time since the rodents were there,” Mr Fleming said.
The Lord Howe wood-feeding cockroach, presumed extinct on the main island, has meanwhile been rediscovered at a site in the north of the island.
Experts have also rediscovered four species of snail previously thought to be extinct.
Mr Fleming said the successful conservation of the woodhen in particular was a great example of what could be achieved.
“It’s a real symbol now for how, if you get the settings right for threatened species, you can get a great result,” he said.
“If you remove the threats and provide good, practical, boots-on-the-ground protection, these species can rebound.
“So really Lord Howe, which has always been spectacular, is now coming alive again, with all of these rare and endemic species found nowhere else in the world.
“This success is built on a great community effort; the island community has done a really great job.”
NSW Minister for Environment James Griffin said the results were “extraordinary”.
“The NSW government’s rodent control program is a world first for a permanently inhabited island, and the results for the biodiversity on Lord Howe are remarkable,” he said.
More work to be done
The recent woodhen census was conducted by a team of staff from the Lord Howe Island Board, Taronga Conservation Society Australia and contractors who systematically searched the remote island for three weeks.
Mr Fleming said monitoring of plant and animal species would continue.
“There’s a lot of science still to do,” he said.
“Because when you remove a threat like this, obviously we get a bounce back in native species, but we are also seeing a bounce back in some of the weed species.
“So, you really have to track everything that’s happening on the island and respond to any unintended consequences.”
There will also be a focus on maintaining strong biosecurity measures.
“I was in Port Macquarie only in the past week, talking to some of the team who do the biosecurity at that end, making sure rats don’t get on the supply boat that goes [from there] across to Lord Howe Island,” he said.
Mr Fleming said the rebounding wildlife would be obvious to visitors to the island.
“Many of the woodhens are actually in the settlement area … so you will see so many more than you did even 12 months ago,” he said.