Abstract
The experimental area was located on Tokawa-cho, Choshi City, Chiba, in which the acrylic panels were fixed to the shore rocks and exposed to the barnacles settlement for a given time. In experimental tanks, barnacles settled on the panels were consumed by the limpets which are commonly seen at this shore. The limpets used could be categorized into four groups; L1 (4∼5mm), L2 (8∼9mm), L3 (12∼13mm) and L4 (22∼23mm). The groups L2 and L4 respectively consumed 24 barnacles larvae for 18 hours, and the group L3 8 larvae, but the group L1 could not consume barnacles of any size.
The limpets of 1.79∼3.16cm shell length damaged the barnacles larvae which had grown up to 1.2mm in about 14∼15 days after their settlement. The other predious shell, Thais claviger, is emphasised as one of the grazers in this shores, and it might consume more barnacles larvae than limpets, though details are unknown.
According to the above observation, the influence of limpets on the formation of barnacles' life zone could be discussed, especially on the critical period of barnacles just after their settlement.
