Loko Iʻa

Loko iʻa are Hawaiian fishponds. They are a form of aquaculture with very few parallels anywhere in the world, and at their height there were hundreds of them across the islands.

What makes them unusual

Most historical aquaculture traps fish and holds them. Loko iʻa do something more sophisticated: they raise them.

The characteristic mechanism is the mākāhā, a grated sluice gate set into a wall. The spacing of the grate lets small fish pass through freely into the pond, where they feed on algae in warm, sheltered, nutrient-rich water. As they grow they can no longer fit back out. The pond becomes a place fish enter voluntarily, grow, and cannot leave.

The result is a system that produces food continuously rather than seasonally, requires no feeding, and is harvested as needed. Estimates of yield from well-managed ponds are high enough that loko iʻa are best understood as infrastructure, not as a fishing technique.

Kinds of pond

Not all loko iʻa are the same. Some are built on the reef flat, enclosed by a curved seawall of stacked stone. Others are inland, taking advantage of natural depressions, springs, and stream flow behind the shoreline. Some are integrated directly with loʻi kalo, so that the same water system serves both.

Inland ponds of the kind found behind dunes and river mouths are fed by a mix of fresh and salt water, and that brackish balance is part of what makes them productive. It is also what makes them sensitive. Change the flow of water into or out of one and the whole system responds.

Loko iʻa today

Many loko iʻa were filled, built over, or cut off from their water sources during the last century and a half. A number are now being brought back by community organizations and practitioners across the islands, and that work has produced a considerable body of knowledge about how these systems function and what restoring one actually requires.