Metamorphosis from a pelagic to a benthic stage is a critical transition in the life cycle of sessile marine invertebrates. The barnacle Semibalanus balanoides attaches permanently during settlement, and once attached, its gross location in the adult habitat is fixed. The partitioning of benthic habitat among barnacles in a recruit cohort is often mediated by settlement timing because early set...

We propose an integrative approach that explains patterns of recruitment to adult populations in sessile organisms by considering the numbers of individuals and their body size. A recruitment model, based on a small number of parameters, was developed for sessile organisms and tested using the barnacle Semibalanus balanoides, a marine invertebrate inhabiting North Atlantic intertidal shores. In...

Chthamalus anisopoma is a rock-inhabiting barnacle which appears in two radically different morphs: the shell may be either conical or bent at a right angle. Based on field experiments, it was previously concluded that the two morphs are phenotypic variants, with the bent morph being induced by the presence of a predator gastropod. In the present study we used molecular data in order to examine...

Gregarious settlement, an essential behavior for many barnacle species that can only reproduce by mating with a nearby barnacle, has long been thought to rely on larval ability to recognize chemical signals from conspecifics during settlement. However, the cyprid, the settlement stage larva in barnacles, has one pair of compound eyes that appear only at the late nauplius VI and cyprid stages, b...

Secreted anterior adhesives, used for temporary attachment to epithelial surfaces of fishes (skin and gills) by some monogenean (platyhelminth) parasites have been partially characterised. Adhesive is composed of protein. Amino acid composition has been determined for seven monopisthocotylean monogeneans. Six of these belong to the Monocotylidae and one species, Entobdella soleae (van Beneden e...

Acorn barnacles of the genus Tetraclita are common space occupiers in the intertidal zone of rocky shores in tropical and subtropical waters (Newman and Ross 1976). In spite of their ecological importance, there is taxonomic confusion about these barnacles because of their high levels of morphological variation. Darwin (1854) considered T. squamosa to constitute a complex with 12 subspecies. Ov...

A focus on the development of nontoxic coatings to control marine biofouling has led to increasing interest in the settlement behaviour of fouling organisms. Barnacles pose a significant fouling challenge and accordingly the behaviour of their settlement-stage cypris larva (cyprid) has attracted much attention, yet remains poorly understood. Tracking technologies have been developed that quanti...

We tested the hypothesis that nutrient enrichment affects recruitment of the oyster Saccostrea glomerata and the barnacle Hexaminius popeiana, which are dominant occupiers of space on tree trunks in temperate mangrove forests in New South Wales, Australia. We measured recruitment on artificial settlement plates at high and low intertidal levels under ambient conditions and where we manipulated ...