KOHALA COAST — Cody Dwight hopped in a chopper for a flyover of Kohala Mountain and was thrust into what he described as a scene straight out of the BBC’s acclaimed nature program, “Planet Earth.”
KOHALA COAST — Cody Dwight hopped in a chopper for a flyover of Kohala Mountain and was thrust into what he described as a scene straight out of the BBC’s acclaimed nature program, “Planet Earth.”
“The entire hillside was moving,” Dwight said. “It looked more like the Serengeti than Hawaii.”
What Dwight witnessed was a herd of feral ungulates galloping across a mountainside they’ve decimated over the years through overgrazing.
He couldn’t put a precise number on it, but Dwight guessed there’s well over 1,000 goats roaming the mountain unchecked. And goats aren’t the only threat. Wild pigs live there in mass quantities, too.
Dwight, coordinator of the Kohala Watershed Partnership, said ungulates pose the greatest threat to the region’s watersheds, though they are hardly the only concern. Deforestation, invasive plants, climate change and diseases, like rapid ohia death, all threaten Hawaii Island’s watersheds, and by extension, its water stores.
Facing a multitude of obstacles, the partnership is addressing the largest concern first — ungulates.
To help them do so, the National Oceanic and Atmospheric Administration recently awarded the partnership with nearly $650,000 for fiscal year 2017 through its community-based restoration program.
The money will be used to fence off approximately 8,500 acres of what the partnership refers to as the Kawaihae 1 watershed and remove up 1,000 feral goats from the landscape, according to a release from the office of Sen. Mazie Hirono.
The partnership will use the majority of the funding to construct about 9 miles of 4-foot hog wire fence, built of galvanized steel, meant to keep ungulates at bay.
Since the decimation of the overstory and understory — which were made up of native plants and trees that helped slow the flow of water down the mountain after large rain events, allowing it to percolate the soil and replenish aquifers — the grasslands are the last solid line of defense against torrents of water rushing to the ocean, carrying with them a substantial portion of the area’s water supply and eroding the mountain in the process.
“Now we don’t have that ground cover anymore, so when we have these large storm events and overgrazing from unmanaged ungulates, that water just hits the surface layer and it’s off and running,” Dwight said.
He added erosion has worsened with more severe weather events, bringing with it threats like mudslides. A smaller mudslide occurred in Kawaihae in 2015, Dwight said, after a fire that was immediately followed by a storm producing powerful rains. The erosion that occurred in that incident flattened about 3,200 feet of steel fence.
It’s erosion that has caught NOAA’s attention, not the first organization one might consider when it comes to land-based endeavors to protect watersheds.
But Katie Ersbak, planner for the statewide Watershed Partnerships Program, of which the Kohala Watershed Partnership is a part, explained that in places like Hawaii, what happens mauka quickly impacts events makai.
Heavy runoff full of sedimentation disrupts the ecology of nearshore waters, she said. It impacts nutrient cycling and further endangers Hawaii’s coral reef systems — already under siege from rising ocean temperatures that have led to the worst coral bleaching events in history over recent years.
While aesthetics aren’t the concern of either NOAA or the partnership, Ersbak explained there are also tourism concerns to consider.
“People don’t want to go into the water if there’s a bunch of muck floating around,” she said.
The rest of the NOAA grant will fund an outplanting of several thousand native trees across 10 acres and help pay to construct 20 sediment check dams — rock walls built in head cutting gullies that allow water to run through to the ocean but check the flow of eroded soil.
“Check dams are not a solution, but they treat symptoms,” Dwight said.
The grant is part of a three-year partnership, and as much as $1.5 million in total might come Kohala’s way through 2019. The fate of the other roughly $850,000, which would be dispersed over the next two years, is tied to NOAA’s Habitat Conservation and Restoration budget. The program funding the watershed partnership’s ungulate management is a part of that budget.
The Trump administration has shifted federal priorities since assuming office in January and has proposed cuts to the NOAA budget that might affect the ability to fund the watershed partnership’s grant in its entirety, as well as several other environmentally-based endeavors currently backed by federal funding.
“Protecting and restoring our forested watersheds is critical for the health and function of Hawaii’s ecosystems,” Hirono said in the release.