Comparison of Hole and Seaweed Habitats of Post-Settled Pueruli and Early Benthic Juvenile Lobsters, Panulirus-Japonicus (Von Siebold, 1824)

Abstract

The habitats used by pueruli and early bcnthic juvenile Panulirus japonicus were examined at 5 locations along the coast of southern Japan. At Kawazu in the Izu area, from reefs covered by agar algae (Rhodophyta: Gelidiaceae) and Ecklonia cava (Phaeophyta), of a total of 67 juveniles sampled, 64 were sampled from small holes in the rock face and 3 specimens were taken from within the agar algae. At the remaining 4 locations, no agar algal beds occurred and the macroalgae cover was dominated by Laminariaceae and/or Sargassum spp. At these sites, the 81 pueruli and 268 juveniles sampled were observed only within holes on the reef surface and not in association with the macroalgae. Diurnal use of both small holes and the dense foliage of agar algae, allows almost complete concealment of the main part of the body of the juvenile which may not be provided by other macroalgae. Agar algae, however, occur intermittently along the coast of Japan, with extensive beds being found only in the Izu area. It is concluded that holes within the reef face, rather than seaweed, are the main diurnal microhabitat of post-settled pueruli and early benthic juvenile P. japonicus.