According the research and reporting by noted archaeologists, 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.
The Hawaiian walled fishpond stands as a technological achievement unmatched elsewhere in island Oceania. Hawaiians built rock-walled enclosures in near shore waters, to raise fish for their communities and families. It is believed these were first built around the fifteenth century.
Only in Hawaiʻi was there such an intensive effort to utilize practically every body of water, from seashore to upland forests, as a source of food, for either agriculture or aquaculture.
The ancient Hawaiian fishpond is a sophisticated land and ocean resource management technique. Utilizing raw materials such as rocks, corals, vines and woods, the Hawaiians created great walls (kuapā) and gates (mākāhā) for these fishponds.
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.
The cultivation of fish took place in Hawaiian agricultural pondfields as well as in specialized fresh and brackish water fishponds. Walled, brackish-water fishponds were usually constructed on the reef along the shore and one or more mākāhā.
Samuel M. Kamakau points out that “one can see that they were built as government projects by chiefs, for it was a very big task to build one, (and) commoners could not have done it (singly, or without co-ordination.)” Chiefs had the power to command a labor force large enough to transport the tons of rock required and to construct such great walls.
In 1848, when King Kamehameha III pronounced the Great Māhele, or land distribution, Hawaiian fishponds were considered private property. This was confirmed in subsequent Court cases that noted “titles to fishponds are recognized to the same extent and in the same manner as rights recognized in fast land.”
Lo‘i Kalo (terraced pondfields)
A second technological invention by Hawaiian Polynesians was the development of their extended stone-faced, terraced pondfields (lo‘i) and their accompanying irrigation systems (‘auwai) for the intensive cultivation of wetland taro (kalo.)
The terraces were irrigated with water brought in ditches from springs and streams high in the valleys, allowing extensive areas of the valleys to be cultivated. The irrigation ditches and pondfields were engineered to allow the cool water to circulate among the taro plants and from terrace to terrace, avoiding stagnation and overheating by the sun, which would rot the taro tubers.
An acre of irrigated pondfields produced as much as five times the amount of taro as an acre of dryland cultivation. Over a period of several years, irrigated pondfields could be as much as 10 or 15 times more productive than unirrigated taro gardens, as dryland gardens need to lie fallow for greater lengths of time thin irrigated gardens.
In addition, walled pondfields not only produce taro, but were also used to raise an additional source of food, freshwater fish: primarily the Hawaiian goby (‘o‘opu nakea) and certain kinds of shrimp (‘opae.)
Captain George Vancouver visited O‘ahu in 1792 and wrote about the taro gardens in tine Waikīkī-Kapahulu-Mo‘ili‘ili-Manana complex that he observed:
“Our guides led us to the northward through the village [Waikiki], to an exceedingly well-made causeway, about twelve feet broad, with a ditch on each side. This opened to our view a spacious plain…the major part appeared divided into fields of irregular shape and figure, which were separated from each other by low stone walls, and were in a very high state of cultivation.”
In 1815, the explorer Kotzebue added to these descriptions by writing about the gardens and the artificial ponds that were scattered throughout the area:
“The luxuriant taro-fields, which might be properly called taro-lake, attracted my attention. Each of these consisted of about one hundred and sixty square feet, forms a regular square, and walled round with stones, like our basins. This field or tank contained two feet of water, in whose slimy bottom the taro was planted, as it only grows in moist places. Each had two sluices. One to receive, and the other to let out, the water into the next field, whence it was carried farther.”
Dryland Field System
The third form of subsistence intensification involved the systematic cultivation of dryland crops in their appropriate vegetation zones as exemplified by the Field Systems in Kona, Kohala, Kaupō and Kalaupapa (Ka‘ū reportedly also has a field system.)
Cultivation of the soil in Kona was characterized by a variety of non-irrigated root and tree crops grown for subsistence, each farmer having gardens in one or more vegetation zones. Each crop was cultivated in the zone in which it grew best.
Reverend William Ellis described the area behind Kailua town in Kona above the breadfruit and mountain apple trees as, “The path now lay through a beautiful part of the country, quite a garden compared with that through which they had passed on first leaving the town.”
“It was generally divided into small fields, about fifteen rods square fenced with low stone walls, built with fragments of lava gathered from the surface of the enclosures. These fields were planted with bananas, sweet potatoes, mountain taro, paper mulberry plants, melons, and sugar-cane, which flourished luxuriantly in every direction.”
Farmers found, farmed and intensified production on lands that were poised between being too wet and too dry. Archaeological evidence of intensive cultivation of sweet potato and other dryland crops is extensive, including walls, terraces, mounds and other features.
The fields were typically oriented parallel to the elevation contours and the walls; sometimes these were made up of a grid of rain-fed plots, defined by low stone field walls built, in part, to shelter sweet potatoes and other crops from the wind.
Since the dryland technique was away from supplemental water sources, this was truly dryland agriculture. There was no evidence to level terraces as in irrigated pondfield systems (taro lo‘i,) and there was no evidence of water control features or channels; so the conclusion was the system was strictly rainfed.
The inspiration (and much of the information) for this post came from research from Dr. Marion Kelly. The image is a portion of an 1893 map prepared by Wall showing pondfields and fish ponds in Waikīkī (note, the “rice fields” used to be taro loʻi.) In addition, I have added other images in a folder of like name in the Photos section on my Facebook page.