‘True ingenuity’: the battle to save Hawaii’s historic fish ponds

On a clear day, Ku’uleini Keakealani peers into the Kīholo fish pond on the west coast of Hawaii Island, Hawaii, and sees an abundance of fish.

It’s a sight for sore eyes – Keakealani knows all too well how the development of the Big Island has threatened delicate ecosystems, waterways, and Indigenous ways of life. Her ancestors were once stewards of this place.

This particular fish pond, sandwiched between five-star resort hotels, is just one of many that Keakealani and her peers have sought to restore. There are dozens of these man-made, rockwall-enclosed sites across Hawaii, including one spanning 88 acres, and for centuries, Native Hawaiians have used these ponds to raise fish to feed their communities.

But over time, the ponds have been neglected, damaged by molten lava, polluted with the litter of island-hopping tourists, and in some cases overrun by mangrove trees, which can destroy fish ponds with their roots and dense biomass. Just over a decade ago, these ponds were almost barren of the native fish species that once fed families.

Today, however, Keakealani watches over the ponds that are now brimming with marine life.

“The ponds remain as one of many examples of the genius engineering and true ingenuity of our kupuna [elders],” Keakealani explains. “We relearn, re-establish, revitalize and reassume our places as kiaʻi loko [guardians].”

The fish ponds are seen not only as nurturing grounds for fish but as an important habitat for other native species. Each day, 3m to 5m gallons of submarine groundwater flows through the ponds and into the ocean, aiding the coral reefs and reef fisheries, according to the non-profit Nature Conservancy.

The ponds are also sacred to Hawaiians. Not only are they a relic from the past, reconnecting communities to their aquaculture heritage, before the islands were occupied by the US, but they provide vital cultural and physical sustenance to the Indigenous communities of today.

For the last decade, coalitions of community groups have been working with the Nature Conservancy to restore the fish ponds, both as a point of cultural pride and as a means to enhance the resilience of the coastline and address food insecurity. The ponds have been dredged to restore them to their original depths, the pond walls have been rebuilt, mangroves have been cleared and hundreds of volunteers gather at the ponds regularly to remove overgrown vegetation from around a pond’s edge and remove invasive species using handheld nets.

The efforts are starting to pay off.

At the 3.2-acre Kīholo pond, there has been a tenfold increase in the fish population since restoration work began in 2012, gains that are important to a state where food insecurity has been climbing at an alarming rate. Other restored fish ponds are similarly seeing gains.

Since 2019, there has been a 51% increase in the number of Hawaii residents who are food insecure, with the pandemic exacerbating an already serious problem. Almost half of families in Hawaii are struggling to feed themselves, and Native Hawaiians are particularly affected, with two in five families relying on food banks.

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“Food security is a really big issue here,” said Kim Falinski, a scientist who works for the Nature Conservancy in Hawaii.

Koa Shultz, executive director of the non-profit community group Kākoʻo ʻŌiwi, the organization that led the clearing of the mangroves, sees the fish pond efforts as part of a larger battle to restore the coastlines, as development rapidly erodes culturally and ecologically valuable areas.

“Our way of life is rapidly disappearing,” he said. “We are struggling for enough land to feed ourselves, and water to grow our crops. Resources are scarce on the island, and yet millions [of tourists] still come.

“We hope that the kind of work that is being carried out here, such as land restoration and Indigenous communities taking the lead, will be relevant to other areas in the world that are suffering similar issues,” he said.

Keakealani also said the work to restore the fish ponds had greater significance for Hawaii. “There’s so much more that happens when spaces like loko iʻa [fish ponds] are restored,” she said. “As we work to restore them, we also work on restoring ourselves as well.”