Abstract
The natural distribution of the juvenile Chilean sea urchin Loxechinus albus was investigated to understand the ecology of the juvenile period from May 1987 to February 1989 in eastern coastal waters of Chiloé Island, Chile. Searching for juveniles by scuba diving and observing suspended bivalve culture lines was conducted. Juvenile L. albus at 38.5 individuals/m2 were found in Linao in February 1989. This was the maximum density noted in this study, and the juvenile size was 2.8-7.8 mm in test diameter. The habitat of juveniles was at the tip of the peninsula, where tidal drift was optimal and the depth was less than 6 m. Moreover, the bottom was pebbles or rock bed, and shell detritus or gravel was found. On the other hand, juvenile L. albus were also found on the suspended culture lines for oysters in Linao and Hueihue. Especially in Linao, approximately 540000 juveniles of 3.5 mm in test diameter were observed attached to suspended oyster culture lines in December 1988. The possible predation of juvenile L. albus in natural waters by juvenile crabs was suggested. According to findings on juvenile ecology, a fishing bank formation mechanism was discussed.
