Quantifying the physical and biological attributes of successful ocean seeding sites for farm-reared juvenile abalone (Haliotis midae)

摘要

In short term experiments of under 3 mo, carried out in McDougall's Bay, on the northwest coast of South Africa, survival of seeded juvenile abalone (Haliotis midae) has been shown to be directly linked to both tile size of the abalone at seeding and to the physical attributes of the seeding site. The presence of the sea urchin (Parenchinus angulosus) has been shown to be insignificant in terms of short-term survival of juvenile H. midae. Within the context of selecting the right seeding site attributes, short-term survival was shown to be up to a minimum average of 59 percent for animals with an average size of 26.61 mm (SD +- 1.33 mm), compared to a minimum average of 24 percent for animals with an average size of 13.87 mm (SD +- 1.73 mm). The fact that the presence of urchins played no significant role in the survival of juvenile abalone, ranging in size from 13 to 27 mm, changes the idea of what the characteristics of successful seeding sites might be. A positive correlation has been established between habitat consisting of stacked boulders, of diameter less than 30 cm, and abalone survival.