Nursery and grow-out culture of the abalone Haliotis asinina on a reef flat: A comparison of growth and survival using different culture containers

Abstract

The study was conducted to compare four different culture containers [cage, recycled oil container, tray (control), and tube] in the nursery and grow-out culture of the abalone Haliotis asinina on a reef flat. For nursery culture, early juvenile abalone with mean shell length (SL) of 1.30 ± 0.006 cm and mean body weight (BW) of 0.45 ± 0.007 g were stocked in the containers at 100 ind m−2 and reared until they attained the 3 cm SL size required for grow-out culture in three of the four culture containers. For grow-out culture, juvenile abalone harvested from nursery culture with mean SL of 3.23 ± 0.018 cm and mean BW of 7.33 ± 0.131 g were stocked in the containers at 50 ind m−2 and reared until they were harvestable at 5 cm SL cocktail size in three of the four culture containers. The 3 cm SL grow-out size was attained at 90 days of culture (DOC) in recycled containers, trays, and tubes, while the 5 cm SL cocktail size at 180 DOC in the same containers. Abalone reared in tubes had the highest mean SL after 90 DOC in nursery culture (3.21 cm), while those in trays after 180 DOC in grow-out culture (5.30 cm). However, at the end of the nursery and grow-out culture, there were no significant differences in mean SL among the abalone reared in these three culture containers. In both culture phases, abalone reared in cages had the lowest mean SL, 2.88 and 4.44 cm, respectively. Survival was highest in trays (98.64%) during nursery culture and in tubes (96.57%) during grow-out culture. With comparable results in recycled containers, trays, and tubes for both growth and survival at the nursery and grow-out phases, tubes are recommended for use when culture is to be done on reef flats. Tubes are the most stable and durable among the four culture containers tested. They can withstand strong winds and waves and may be reused for several culture runs.