The video, grainy and almost colorless, resembles security camera footage.
A feral cat crouches on lava rock, pausing before it enters a small crevice in the rock, its tail disappearing into the hole.
In the next shot, the cat emerges with a kill and bounds away.
The footage is taken from a National Park Service game camera and depicts an event staffers at Hawaii Volcanoes National Park hope won’t be happening again any time soon: the killing of an endangered storm petrel chick.
Feral cats are such a threat to Hawaii Island’s native storm petrel, or ‘ua‘u, population that a cat-proof fence was recently completed on the slopes of Mauna Loa in an effort to protect the birds and their chicks during nesting season.
The fence spans 5 miles and encompasses 600 acres of park habitat. More than 6 feet high, it is curved at the top to prevent cats from climbing over.
Work on the project began in 2013.
The fence is located at a remote site located at elevations between 8,000 and 10,000 feet on Mauna Loa. All materials and construction equipment — along with work crews — had to be flown in via helicopter.
“To our knowledge, this is the largest fence of its kind in the U.S.,” NPS biologist Kathleen Misajon said in a statement. “To build such a fence is an incredible feat, and an important victory for a native species that is extremely rare on Hawaii Island.”
There are 75 nesting pairs of storm petrels at the national park, in addition to a smaller group that lives on Kohala’s slopes.
The storm petrel spends most of its life at sea. It comes ashore only during breeding and nesting season. ‘Ua‘u arrive in April to prepare nests in lava rock crevices. They return in early June to these burrows, where they lay a single egg. Both parents take turns incubating the egg and feeding the chick.
Chicks hatch in August and stay in the burrow until November.
Because nesting takes place on the ground, storm petrels are vulnerable to predation during this time.
Construction cost just more than $1 million, park spokeswoman Jessica Ferracane said. Most funding came from the park service, with help from the U.S. Fish and Wildlife Service, the American Bird Conservancy, Hawaii Pacific Parks Association and National Fish and Wildlife Foundation.
The Pacific Cooperative Studies Unit at the University of Hawaii also worked on construction.
Elsewhere in Hawaii, a cat- and rat-proof fence protects nesting seabirds at the Kilauea Point National Wildlife Refuge on Kauai. That fence encompasses just less than 8 acres.
There also are fenced enclosures on Maui and at Kaena Point on Oahu.
Email Ivy Ashe at iashe@hawaiitribune-herald.com.
