Aquacultural fishpond technology allowed the ancient Hawaiians to move beyond mere harvesting of fish and other marine products (i.e. crustaceans, shellfish, and seaweed) to intensive fish production and husbandry.
Reportedly, a total of 449 ponds that were constructed prior to A.D. 1830, most during the prehistoric period. They were built on all the major islands.
Broad shallow reef flats or natural embayments provided an environment where ponds could be constructed easily in sweeping semicircular arcs out from the shoreline.
Along the shoreline were ponds with (kuapa, or pa) and sluice gates (mākāhā). The distinctive feature of the kuapa ponds was the sluice gates.
The mākāhā was stationary with no moveable parts. This was the technological innovation, probably an adaptation from an earlier form used in irrigation agriculture (taro), that enabled the Hawaiians to progress from tide-dependent fishtraps to artificial fishponds which could be controlled at all times of the tide.
Ponds varied in form, construction, methods of operation, and in the species of fish raised. Ponds or loko, were divided into two major categories: shore and inland ponds.
Huilua Fishpond at Kahana Valley in Koʻolauloa on the Island of Oʻahu has been traditionally classified as a loko kuapa pond. It was a working fishpond (with modifications) until the late-1960s.
Huilua Fishpond is one of only six remaining fishponds out of an estimated ninety-seven such structures that once existed on
coastal Oahu and one of the few ancient Hawaiian fishponds that were still operational well into this century.
It is also one of only ten ponds left in the Hawaiian Islands which have not been denuded of their archeological sites during the course of historic coastal development. A large majority of ponds throughout the Islands have also been destroyed by natural agencies such as tsunamis (tidal waves) and sea storms.
Huilua is a shallow, brackish water enclosure of approximately 4 ½-acres that is roughly shaped as a right triangle with the right angle of the base forming the northwest or seaward corner of the pond.
The base or western wall abuts and partially deflects the effluent from the Kahana estuary as it discharges into Kahana Bay. This wall, approximately 500 feet in length.
At the extreme south end of the western wall are located two parallel mākāhā or sluice gates. The makai gate is longer by approximately 10 feet than the mauka gates.
Huilua Pond has been an important element in the long-term habitation of Kahana Valley and is expressive of that habitation. It was an important part of the valley’s cooperative subsistence economy from the late 19th Century until the late-1960s.
At that latter time, the konohiki fishing rights for Kahana Bay were condemned and acquired by the State of Hawaiʻʻi to allow public access to the bay.
Huilua Pond became a part of Kahana Valley Cultural Park, a ‘living park’ concept developed by the Hawaii Department of Lands and Natural Resources whereby approximately 150 persons, many of whom grew up there, reside in the Park.
The ancient Hawaiians believed that walled fishponds of the loko kuapa type were inhabited by moʻo (water spirits) who were also akua (gods) and kiaʻi (guardians) and relied upon them to protect the ponds in order to assure an abundance of fish.
Ritual pollution included the violation of kapu (taboos, i.e., women could not fish nor be involved in the work of the pond), neglect of ritual obligations associated with the pond, poaching, and so on.
Informants on the Kahana Valley oral history project related: ‘Huilua Fishpond has a moʻo that lives in a deep hole at the northwest corner of the fishpond where the western wall meets the northern.’
When the moʻo leaves the pond and then later returns ‘there are always dried leaves floating on the top of the water to indicate its presence’.
Oral history informants from Kahana Valley also related that their elders and grandparents propitiated the traditional fish god Kuʻula, otherwise the fish might disappear from the pond.
While the koʻa was not used within living memory, they reported that a fish stone (pohaku kuʻula) required prayers and proper care in order to keep the fish in the pond. The location of the sacred stone is not clear. (Lots of information from NPS and DLNR.)