The Garden Island
LEHUA — Two Border Terriers spent most of last week crisscrossing the rugged, hot, wind-swept terrain of tiny Lehua Island.
Lehua is a State Seabird Sanctuary and the site of an intensive restoration project over the past nine months to protect seabirds by removing invasive rats.
In 2017, the partners of the Lehua Island Restoration Project applied a conservation bait to remove the population of invasive Pacific rats which eat the chicks of nesting seabirds and devour the native plants that help support a large variety of bird life here.
Since the operation last summer, monitoring teams continue to observe more albatross on Lehua Island than previously seen. There continues to be no sign of rat predation on plants or seabird eggs, something that was commonplace a year ago.
“Whole island eradications are very complex and seeing a few surviving rats is a reflection of this,“ explained Sheri Mann, Kauai branch manager for the DLNR Division of Forestry and Wildlife. “The Lehua Island Restoration Project Partnership is working to ensure the island is free of invasive rats. An extensive network of motion-triggered cameras picked up seven rat images since last fall and the team is working diligently to address the situation.”
That’s where the small dogs come in. Border Terriers have a long-established reputation of being able to pick up the scent of rodents.
Henry, 6, and Reese, 3, are owned by Charlotte Metzler of Hawi, Hawaii Island, who along with certified professional dog trainer Kyoko Johnson of Country Canines spent months preparing the pair for their Lehua deployment.
The training included trips to Oahu’s Kaena Point Natural Area Reserve. The natural environment there closely duplicates what the dogs encountered on Lehua.
“The major thing we wanted to do in training is to desensitize the dogs to the presence of seabirds, so they can focus on their task of finding rats above ground or in burrows,” Johnson said.
Once Henry or Reese caught the scent of a rodent, their human handlers and monitoring staff with DOFAW and Island Conservation marked the location.
“With the help of these dogs, we are able to actively search for recent rat activity and can tailor more effective responses of those specific areas,” said Mele Khalsa of Island Conservation.
It was a tough week of sniffing for Henry and Reese. The grass on Lehua was well over their heads and much of the ground they traversed was steep, loose lava rock.
While Lehua is only 279 acres in size, its topography made the canines’ rat search very challenging with the need for lots of water and rest stops.
Dogs have been successfully used in other conservation projects around the world. Conservation detection dogs have been used previously in Hawaii to locate endangered species like the Hawaiian hoary bat and the wedge-tailed shearwater to measure impacts of wind farms.
The U.S. Fish and Wildlife Service, one of the partners in the Lehua restoration effort, used dogs in a pilot study to try to detect avian botulism in the Koloa Maoli, the endangered Hawaiian duck.
During their first deployment to Lehua, the dogs showed significant interest in three locations. All of these potential rat burrows were targeted for additional bait application and marked to check in the future. Plans are being made for Henry, Reese and their handlers to return to Lehua for additional searches.