The clouds cleared around Kauai and Ni’ihau Wednesday morning and the Lehua Island restoration project began.
“Well, they’re doing it. We’ll see what happens,” Harold Vidinha said as he and his son Kevin guided their fishing boat through the channel between Lehua and Ni’ihau at about 7 a.m.
For the next four hours, the island was carpeted with poison-laced rat bait, dropped by helicopter, which fell onto the top of the island, through the stark, rocky cliffs that lead to the ocean, and onto the shoreline.
In between loads of green pellets containing cereal grains and the restricted use pesticide diphacinone, Hawaiian monk seals swam between the fishing boat and shore, green sea turtles showed their faces, and spinner dolphins put on a few short shows.
The operation’s goal is to rid the island of a widespread invasive rat infestation. The rats forage on native plants and seeds, as well as the young of birds that nest on the island.
“The operation was executed as planned — successfully, safely and under the close watch of regulators from the Hawaii Department of Agriculture, and an independent monitoring team from the U.S. Department of Agriculture,” according to a press release from the Department of Land and Natural Resources,
“I am pleased with the planning, preparation and execution of this project to restore Lehua Island. It was carried out very professionally and with the utmost care,” said Scott Enright, head of HDOA and the man who oversaw the operation from the ground on Ni’ihau.
DLNR is partnering with the non-governmental organization Island Conservation and the U.S. Fish and Wildlife Service on the project.
Once the rats are gone, the plan is to introduce native Hawaiian plant species to Lehua and create a bird sanctuary, hopefully inviting other species — like Newell’s shearwaters — to nest there.
Lehua Island, also known as Lehua Rock, is a horseshoe shaped landmass with steep cliffs, rocky ledges and little vegetation. It is home to 17 seabird species and 25 native plants.
“It’s a good place for ‘opihi. People from Ni’ihau, they come gather here all the time,” Vidinha said.
Wednesday kicked off multiple helicopter trips back and forth from the bait and refueling station on Ni’ihau to Lehua. In addition to aerial broadcast of the poisoned bait, the operation used people on the ground to hand distribute the bait.
The main concern of residents was that the pellets would end up in the water and harm marine life — including some endangered species. But, the project secured state and federal permits that allow a “negligible amount of bait drift into shallow near-shore waters,” according to DLNR.
“The permits also acknowledged that this poses little risk to the environment,” the release said. “Lab studies have shown that fish reject bait containing diphacinone. Furthermore, fish are among the least likely animals to be affected by the rodenticide. What little bait drifts into water from the over-land application sinks to the sea floor and degrades quickly.”
In addition, the bait distributed over the land was done so with deflectors in place to direct the bait inland, according to Patty Baiao, Hawaii program manager for Island Conservation.
“Despite the low risk, the operation is using proven strategies to avoid, minimize, and mitigate risks whenever possible,” she said.
But people on Kauai and Ni’ihau were worried bait pellets would end up in the water, Vidinha said, and he pointed out that some did.
The pellets also collected in tide pools and above the high water mark around Lehua’s shoreline.
As the fishing boat got closer to the shore after a drop about 8 a.m., a black crab snagged a bright green bait pellet and scuttled up the shoreline.
“They said crabs don’t eat it,” Vidinha said.
Using a helicopter to spread bait across the island was also a concern for Kauai residents.
“From a firsthand look, using a helicopter isn’t going to work with that terrain,” Vidinha said. “It’s bouncing right off and into the ocean.”
DLNR Chair Suzanne Case said time will show the plan will be successful.
“A safe, careful, by-the-book operation, together with the downstream conservation outcomes of this project in coming years, will provide the proof-of-concept the community is seeking for this important conservation intervention,” she said in a press release.
Three community meetings about the Lehua Island restoration project on Kauai preceded Wednesday’s operation. Dozens of federal and state permits affirming that the operation poses very little risk to people, marine mammals, fish, sea turtles, birds, or other wildlife were secured in advance of the operation, DLNR said.
The bait drop happened between 6 a.m. and noon and it was the first of three scheduled to happen in the next few weeks, weather permitting, according to DLNR.
When the first drop commenced, the public was notified just before 7:30 a.m. through a press release from DLNR.
“I hope that this killed all the rats and that no other animals are harmed in the process,” said Shyla Moon, board member of the hunting farming and fishing association and Western Pacific Regional Fishery Management Council Kauai advisory member.
She continued: “I’d also like to ask the project managers to give the public future notice before another drop.”
Ultimately, the goal is to bring National Tropical Botanical Garden on board with the project and turn Lehua into a botanical and bird sanctuary.
Lehua is one of the largest and most diverse seabird colonies in the main Hawaiian Islands, but the rats are threatening it.
“The invasive rats forage on native plants and seeds, which imperils the entire ecosystem,” DLNR said. “These impacts can contribute to erosion which can in turn impair near-shore marine and coral ecosystems and fisheries. Native birds like the threatened Newell’s Shearwater are likely being restricted from breeding on Lehua Island due to predation by rats.”
And while people on Kauai are in support of creating a bird sanctuary, they are also concerned about what the diphacinone is doing in the water around Lehua.
Gordon LaBedz, family physician and vice chair of the Kauai Surfrider Chapter, said he supports bird conservation, though he’s not fully on board that the poison will kill just one species.
“Many of our birds have gone extinct and we are losing more all the time,” he said. “Let’s hope that the poison only kills rats and nothing else.”
There will be a monitoring program post-aerial application to address potential environmental concerns, according to HDOA.
The time of when the public was notified of the drop by DLNR was adjusted in this story from just before 8 a.m. to before 7:30 a.m.