The U.S. Army is looking to protect a rare, endangered bird on Oahu.
The Oahu elepaio, a native flycatcher, makes its home in the mountains above the Schofield training range and is found nowhere else in the world.
At just over five inches, the Oahu elepaio is small enough to fit in the palm of a hand, and yet the curious, feisty bird was a guardian spirit to Hawaiian canoe makers, helping them judge the quality of koa trees for potential canoes.
Today, this once thriving and treasured species is struggling to simply survive. Biologists estimate just over 1,200 Oahu elepaio exist, and their population is continuing to decrease due to low reproductive success and adult survival.
The Army says that’s due largely to invasive rats, which can climb trees and prey on elepaio eggs, chicks, and roosting adults.
A single rat and its offspring can produce more than a thousand hungry rats per year. In comparison, the elepaio lays an average of one to two eggs year.
The Army monitors a number of elepaio pairs and supports them with rodent control as a means of offsetting any potential harm military training could cause.
“We’ve been working with the elepaio since the ’90s,” said Kapua Kawelo, Natural Resources program manager, U.S. Army Garrison-Hawaii. “Over the years we’ve used bait stations, snap traps, and more recently, gas-powered, self-resetting traps.
“Unfortunately, these strategies haven’t been as effective as we want. We aren’t able to cover a large enough area due to severe terrain and limited access. As a result, the rat population is still rising,” Kawelo said.
The Army is looking into innovative solutions like rat birth control to limit population growth, but these solutions still need to be tested and proven effective.
In the meantime, the Army is proposing to conduct a broad-scale application of rodenticide in an area where it manages its largest number of elepaio pairs.
The management area is enclosed by fencing and is located in the Waianae Mountains above the Schofield training range.
“It’s a good area for a project like this because it’s fenced to keep pigs and goats out, and it’s not open to the public or service members,” Kawelo said.
Kawelo adds that the project would also benefit other native species rats prey on in the management area, such as the endangered Kahuli tree snail and plants like the endangered haha and mehamehame.
The proposed project would involve dispersing penny-sized rodenticide pellets in the fenced management unit prior to elepaio nesting season using a helicopter and specialized dispersal bucket.
The pellets contain .005% diphacinone and are approved for this type of conservation use by the U.S. Environmental Protection Agency and the Hawaii Department of Agriculture. Multiple measures would be put in place to safeguard health and safety, to include creating no-drop buffer zones around areas with surface waters, like streams; scheduling operations so they don’t occur during forecasted heavy rains; using only licensed applicators; and close monitoring to gauge effectiveness and impacts.
The Army has prepared a supplemental environmental assessment (EA) that analyzes whether the broad-scale application would cause significant environmental effects. Based on that analysis, the Army has also prepared a draft Finding of No Significant Impact (FNSI). The Army will not make a final decision on whether to proceed with the proposed action until after the public’s review.
The public can review the supplemental EA and comment on the draft FNSI during a 30-day public comment period, which runs now through Sept. 7.
The documents are available online here. Printed copies are available upon request and at the Hawaii State Library, Wahiawa Public Library, Waialua Public Library and Waianae Public Library.
Comments can be emailed to email@example.com or mailed to: USAG-HI DPW Environmental Division, 947 Wright Ave., Wheeler Army Airfield, Schofield Barracks, HI 96857.