Fence built to save Hawaii's native birds

To protect Hawaii's native birds, conservationists at the Kīlauea Point national wildlife refuge on the island of Kauai are trying something new: building a sprawling wall around the birds' nesting ground.

The Kīlauea Point national wildlife refuge is aiming to keep invasive species out and encourage native habitat to thrive. While Hawaii is still flush with life today, many of those birds are now gone – roughly 67% of all endemic Hawaiian birds have been wiped from existence since humans first arrived on the islands.

Kīlauea Point holds Hawaii's largest population – approximately 160 pairs – of Nene, an endemic listed as Vulnerable (Chris Hawes).

Although habitat loss – and more recently, climate change – have played a role in that decline, one especially persistent threat to these native birds has been predatory invasive species, which were introduced – inadvertently or otherwise – to the islands by humans.

The fence – the second of its kind in Hawaii – was installed at the behest of the Nihoku ecosystem restoration project, which is dedicated to preserving the archipelago's coastal ecosystems and establishing safe breeding grounds for Hawaiian seabirds.

In 2014, the wildlife refuge unveiled a state-of-the-art, predator-proof fence; standing two meters tall and spanning 624m across, it creates a physical barrier that blocks invasive predators from accessing nesting seabirds and their young. The fence is capped with a rolled hood to stop attempts of climbing over, and an underground extension of its base wards off predators who can burrow and dig.