LIHUE — Lehua island is changing.
Plants are starting to regrow over the rocky, 279-acre, crescent-shaped island about 35 miles across the Kaulakahi Channel from Kauai. The reefs are looking robust and healthy, the seabirds are coming back in abundance.
There are still signs of rats on the islet, too, but so far the Lehua Restoration Project — the goal is to eliminate the rat population and create a seabird sanctuary — is working.
That’s all according to the state Department of Land and Natural Resources Division of Forestry and Wildlife, as well as Island Conservation.
Representatives from those organizations teamed up for an update on the project at the request of The Garden Island, and outlined the status of the project in a written statement.
“There is noticeable positive impact to the environment,” the statement said. “With increased survival of seabirds populating the island, the nutrients they bring to the island have benefits to Lehua from the top of the island all the way to the ocean below.”
In 2017, DLNR teamed up with Island Conservation in a project to eliminate a population of invasive Pacific rats on the island, which eat the chicks of nesting seabirds and plants that support the bird life.
Using an aerial application method with helicopters, the partners blanketed the island in rodenticide pellets, which triggered concern among some fishermen and community members on Kauai.
A major concern was that the rodenticide pellets would impact the fishery and poison marine and potentially bird life in the area.
Project representatives said Friday that monitoring continues on that front and “show(s) no negative impacts from the rat bait pellets on the surrounding environment.”
The last sign of rats on the island were found in early-to-mid 2019, when a monitoring team found some rat fecal pellets. Cameras placed on the island to detect rats haven’t seen one since December, and there are no signs of the rodents in rat traps or in tracking tunnels.
“The population of Pacific rats on Lehua island remains extremely low,” project partners said. “No signs of rat predation have been seen since the island was treated in September 2017. Prior to this date, rat predation was commonly seen across the island.”
The seabird population, on the other hand, is growing, and some species are expanding their range, the most notable being the Bulwer’s petrel.
Though the rat population is nearly non-existent on the island, the birds still face predation from barn owls and cattle egrets.
Many of the plants that are growing back are providing shelter for birds like the Bulwer’s petrel, though most of them aren’t native plants yet. Repopulating the island with native plants is part of the project down the road.
As they rolled out the first few phases of the project, partners said there was a chance for a second aerial application of rodenticide on Lehua should the first fail.
“There are no plans for a second round of aerial rodenticide application at this time. We will continue to monitor the rat population and do spot treatments when and where they are seen and will reassess our strategy if rodent sightings begin to increase,” partners said in their statement.
Dog detection will continue as well, during times when birds aren’t nesting in burrows. Traps have been deployed continuously as monitoring and killing devices, and none have trapped rats since September 2017. Bait stations have also been used to spot-treat at rat-sighting areas.
Source: The Garden Island