An invasive-predator-proof fence just over a mile long has been installed to secure the border of wildlife sanctuary Mokio Preserve on Molokai. It aims to protect ground-nesting wedge-tailed shearwater and to secure invaluable future habitat for Laysan and black-footed albatross, Bonin petrels and Tristram’s storm petrels that nest on the sea-level-threatened shores of the Northwestern Hawaiian Islands.

The $1 million fence, built in partnership by the American Bird Conservancy and Molokai Land Trust, will allow the ground-nesting birds to raise chicks without predation by feral cats, mongoose, rats and mice — costly insurance against extinction.