Title Effects of volcanic ashes of Miyake Island on the behaviour and survival of the small abalone, Haliotis diversicolor diversicolor, under culture conditions
Authers Hideaki AONO, Kentaro NIWA, Toyomitsu HORII and Hiroaki KUROGI
Keywords abalone, Haliotis diversicolor diversicolor, volcanic ashes, Miyake Island
Citation Bull. Fish. Res. Agen. supplement No. 17, 57-62, 2006
Due to the eruptions of Mt. Oyama in Miyake Island from July 2000, accumulation of enormous amount of volcanic ashes was observed on the sea bottom around the island. Since it was not understood clearly how marine benthic animals behave against suspended ashes and how accumulated ashes affect the animals, we examined the effects of volcanic ashes on the small abalone, Haliotis diversicolor diversicolor, under short term culture conditions. When 150-250 g/L of ashes were added to beakers containing abalones, most of the animals immediately began to crowl upward. Some of them detached from the beaker wall and dropped onto the accumulated ashes (about 14 to 22 mm thick), and more than one-third of animals died within 48 hours. Anatomical and microscopic observations of the dead abalones showed that the mantle cavity and the gaps between gill lamellae were filled with ash particles. These results indicate that the abalone avoids suspended ashes, and accumulation of which is leathal to the animals.
URI http://www.fra.affrc.go.jp/bulletin/bull/bull17/aono.pdf