If you’re planning to visit Hawai’i in the near future, you’ll no doubt be lured and amazed by the island state’s beauty. There’s a reason humans include the Big Island in their travel plans every year.

If you’re a cat, however, you’ll find the local attractions to be a somewhat restricted from now on. The state has recently completed one of the largest feline-focused public works projects to date — a 5-mile-long cat-proof fence around the perimeter of Mauna Loa, the world’s largest volcano.

Cats arrived on the Hawaiian Islands likely during one of Captain Cook’s three visits to the island. According to the U.S. Geological Survey’s Hawaiian Volcano Observatory, the progeny of those first few felines now reside on all of the main islands, at every elevation.

Feral cats in Hawai’i.

This coverage by cats has troubled the island for years now, as many of the native ground-nesting birds have been driven to extinction. A particular delicacy of the feral cats, the Hawaiian petrel, or ‘ua’u, is a federal endangered species.

The endangered Hawaiian Petrel.

The dark grey and white birds make a number of calls, according to the National Park Service, including one that makes the sound of their name, ‘ua’u.

But the ‘ua’u’s numbers are dwindling, and estimates split their last remaining nesting sites — containing only 50 to 60 breeding pairs — between northern Kohala and on the subalpine slopes of Mauna Loa.

Mauna Loa is the biggest volcano in Hawai’i, and possibly the largest on earth.

The national park has built a large-scale barrier fence around the primary nesting colony on Mauna Loa, the NPS reports. And the light system has been updated to “minimize disorientation of night-flying petrels.”

Segregating feral cats from petrel populations is crucial to the birds’ survival, and in some cases, more lethal methods have been undertaken. While we cannot deny the importance of population control methods, far more cats are killed every year for the sake of convenience. Follow the button below to sign our petition and help make convenience euthanasia a thing of the past.