Pasua (Tridacna maxima) size and abundance in Tongareva Lagoon, Cook Islands

Pasua (Tridacna maxima), also known as pa’ua, are one of two species of giant clams native to the Cook Islands. Pasua are a culturally significant food item throughout the Cook Islands, and in the Northern Cooks remain a staple food source. Pasua are rare in the southern Cook Islands as a consequence of previous overharvesting but increasing numbers of pasua from the northern Cook Islands, especially Tongareva, are available for sale in Rarotonga. In response to declining numbers in the southern Cook Islands, a giant clam hatchery was established on Aitutaki in 1990 by the Cook Islands Ministry of Marine Resources (MMR) to help reintroduce clams to the lagoon.
The specific aims of the survey were to assess the size distribution, abundance and density of pasua in Tongareva Lagoon.
In addition, this survey aimed to provide baseline information for the Island Council regarding the establishment of specific size limits, the possible need for a rahui (harvest closure), and the ideal location of such a rahui if required.