Perna mussels have been introduced into Japanese waters since 1967. We investigated the occurrence and wintering of the Perna mussels in Ise and Mikawa Bays, central Japan. Most of specimens collected in the bays are identical with Perna viridis, but several specimens were difficult to identify to a specific level based on the past taxonomical studies. It is difficult to identify the specimens of the Perna mussels introduced into Japanese waters where commercial vessels have often come from oversea. Several specimens of P. viridis and Perna spp. were wintering at Nagoya port located in the innermost of Ise Bay and also at cooling water discharge of the Thermal Power Plant in Hekinan city located in Mikawa Bay.

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The adhesion characteristics of marine adhesive proteins and the preparation of antifouling surfaces toward the marine and freshwater sessile animals have been investigated. The attachment of marine invertebrates, blue mussel and barnacle, and the freshwater mussel was tested using non-treated material surfaces, such as glass and silicone, together with glass surfaces modified with nine kinds of silane coupling agents. Based on the relationship between the sessile animal attachment and the surface free energies of the substrates, the percent of sessile animal attachment was significantly reduced for the substrates with lower surface free energies. The mean number of secreted byssuses per one attaching mussel also decreased with decreasing surface free energies of the substrates. The analytical approach based on the component division of the surface free energies of the substrates may suggest a promising strategy for the preparation of antifouling surfaces. Our working hypothesis for the preparation of ecologically clean antifouling materials takes into account the combination of wettability of both the marine adhesive proteins and the modified surfaces. This component division of the surface free energies could be an alternative solution to antifouling material science.

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The present paper deals with growth and attachment of isolated utricles from various parts of thalli in Codium fragile (Suringar) Hariot, with utricles from different stages being studied in laboratory culture in order to select suitable utricles for conducting assays on seaweed attachment. Clavate utricles were observed in the thalli at three stages: utricles without a gametangium, those with a gametangium before and after gamete release, and slender utricles without a gametangium. The clavate utricles were abundant except for the basal parts of the thalli, so that these utricles were used in the present study. The utricles isolated from six parts of the thalli and those at three different stages had the ability to form medullary filaments and attach to the substratum by their elongated filaments. However, the ability of the isolated utricles to elongate their filaments differed among the parts of the thalli used for isolating the utricles, and the ability of the utricles to form and elongate their filaments differed among the stages of the utricles. Furthermore, utricles with a gametangium were obtained only in a certain period when the thalli were fertile. Therefore, the clavate utricles without a gametangium isolated from the higher orders of axes are more suitable for use in assays on seaweed attachment.

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Fouling was studied on ships travelling five main shipping routes in the Far East. Monodominant fouling communities of living sessile organisms comprising 18 to 49 species per ship were found. The biomass density varied from 573 to 4198g/m². A latitudinal gradient of decreasing biomass density was observed from the most southern (Haiphong, Vietnam) to the most northern (Anadyr, Russia) transport route. The maximum number of species per ship showed the same pattern. The species-diversity index increased towards the south, but it abruptly decreased for the ships of the Russia-Vietnam route. The predominance of the barnacles Balanus improvisus and B. amphitrite on ships of the Russia-Japan routes is an indication that these ships may facilitate the introduction of these species to Peter the Great Bay. An analysis of the biogeographical composition of the fouling community revealed a high percentage of warm-water species on ships of the Russia-Japan routes. The incomplete process of acclimatization of the warm-water species B. improvisus, B. amphitrite, and Hydroides elegans in Peter the Great Bay is discussed.

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Among the species of the zooxanthellate stony coral Hydnophora Fischer, which are found throughout most of the Indo-West Pacific faunal province, only a few are known to be parasitized by the coral-eating barnacles comprising the tribe Hoekiini ROSS and NEWMAN, 1995. The single-plated wall in these sessile cirripeds, nestled cryptically between and tending to mimic the hydnons of the host, assumes an unrivaled spectrum of outlines and overall shapes that seemingly defy description. Indeed, the range of disparate morphological features as well as the number of species in this poorly known taxon are far greater than previously believed.
The present collection includes Hoekia monticulariae (GRAY, 1831) from Singapore, and two species from unspecified localities in the Philippine Archipelago, Hoekia philippensis n. sp. and Ahoekia microtrema n. sp. The latter provide insights into the lacuno-circumferential system and structural organization of the marginal fringe, or inner lamina of the wall. Fringe width, height and density, or ratio of solid to void, as well as how the fringe is accessed, varies with each genus, but the net effect is that the surface area covered by tissue, through which it is believed these barnacles mediate their relationship with the host coral, is essentially comparable in all of the species. In a manner similar to certain other invertebrates, such as corallivorous gastropods, these barnacles likely foster the development of energy sink sites that promote regeneration of the tissue consumed by the barnacle.

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