Talk to any rancher and he’ll typically say he’s growing grass, not cattle. The more grass he can grow, the more cattle he can have to harvest it.
So, too, with Hawaiian fishponds; but instead of grass, the pond grows algae. The more algae grown, the more shrimp to eat it, and small animals to eat the shrimp, and small and then larger fish to feed on the pondlife.
Practically every culture in the world has practiced aquaculture (cultivation of aquatic life forms to serve the food needs of man) in some degree.
Ancient Egyptians, Mesopotamians and Assyrians stocked artificial ponds with fish; Greeks and Romans raised oysters, and Romans raised eels. Early Germans bred freshwater fish in ponds. Carp culture spread from Asia Minor and by A.D. 700 was established in Europe. (Apple & Kikuchi)
Hawai‘i had intense true aquaculture. As far as is known, fishponds existed nowhere else in the Pacific in types and numbers as in prehistoric Hawai‘i.
Only in the Hawaiian Islands was there an intensive effort to utilize practically every body of water, from the seashore to the upland forests, as a source of food, either agriculturally or aquaculturally. (Apple & Kikuchi)
There were three main technological advances resulting in food production intensification in pre-contact Hawai‘i: (a) walled fishponds, (b) terraced pondfields with their irrigation systems and (c) systematic dry-land field cultivation organized by vegetation zones. (Kelly)
Hawaiian fishponds are more productive than the natural habitat of coastal reef. The primary fish selected for the ponds were herbivores, usually mullet (‘ama‘ama) and milkfish (awa.)
A fishpond is essentially a pasture, in which algae (limu) is raised as food for the selected herbivores. Cultivation of algae depends on managing the environment of the pond, including fresh water/salt water balance, adequate sunshine for algae growth and seasonal cleaning to allow a fresh growth of algae. (Hiatt; Kelly)
Since the types of algae that mullet consume grow best in brackish water. Hawaiian walled fishponds were often located (a) on the shoreline near the mouth of a stream, (b) where fresh water escapes in springs along the shore, or frequently (c) in the sea. (Kelly)
The general term for a fishpond is loko (pond), or more specifically, loko iʻa (fishpond). Loko iʻa were used for the fattening and storing of fish for food and also as a source for kapu (forbidden) fish.
Loko kuapā, what we consider the typical coastal fishpond, are artificially enclosed by an arc-shaped seawall and containing at least one sluice gate (mākāhā.)
Loko pu‘uone are formed by development of a barrier beach paralleling the coast, and connected to the ocean by a channel or ditch; it’s a shore fishpond containing either brackish or a mixture of brackish and fresh water.
“The large salt or brackish water ponds, entirely enclosed, have one, two or four gates called mākāhā. These are of straight sticks tied on to two or three cross beams the sticks in the upright standing as closely as possible, so that no fish half an inch in thickness can pass them, while the water and young fry can pass freely in and out.” (McDonald)
“After five or six months fish would begin to be seen in the loko kuapā. During the high tides of ʻOle (ʻOle kai nui) the people who took care of the pond would rejoice to see the fish moving toward the kuapa walls, like waves of a rough sea, until the sluice, makaha, was filled with fish.”
“If the depth of the water at the sluice were a yard or more, the width of the mākāhā an anana, and the thickness of the kuapā walls an anana, this area would be filled with fish, piled one over the other until the fish at the top were dry; if a stone were placed on them it would not sink.” (Kamakau)
Fishponds, loko i‘a, were things that beautified the land, and a land with many fishponds was called a ‘fat’ land (‘āina momona.) They date from ancient times. (Kamakau)
It is not known when Hawaiian fishponds began to be constructed, but some fishpond walls have been carbon-dated to the 1400s. An estimate of 340–360 Hawaiian fishponds was noted for the period before the arrival of Captain James Cook in 1778.
An inventory in the early 1900s found 360 loko i‘a in the islands and identified 99 active ponds with an estimated annual production total of about 680,000 pounds, including 486,000 pounds of ‘ama‘ama and 194,000 pounds of ‘awa.
Loko i‘a were extensive operating systems that produced an average of 400–600 pounds per acre per year, a significant amount considering the minimal amount of fishpond ‘input’ and maintenance effort apparent by that time. (Keala)
‘Āina Momona performed by Kawika Kahiapo: