Evidence of early chemotaxis contributing to active habitat selection by the sessile giant clam Tridacna maxima

Drivers of density for the exploited giant clam Tridacna maxima: a meta‐analysis

“…Recruitment success is partly determined by the ability of larvae to find suitable substrate to settle on (Dumas et al . ). In small and enclosed lagoons, high water residence time (Andréfouët et al .…”

“…; Dumas et al . , ). Few studies reported on and explained variability of giant clam densities at wider scale.…”

Distribution of Noah’s giant clam, Tridacna noae

“…In ecological and physiological experiments on the small giant clam (e.g., Ambariyanto 1999;Dumas et al 2014), inadvertently mixing specimens of different species might lead to artefactually inflated variance in response to stimuli. Juvenile production of small giant clams (e.g., Gomez and Mingoa-Licuanan 2006) might be affected by lower fertilization success and higher embryo mortality if individuals of different species are induced to spawn in the same batch.…”

“…In Kosrae, adult small giant clams (22-28 cm) were collected as aquaculture broodstock. At Efate, adult small giant clams (N=10) were collected in the Mangaliliu marine protected area, to be transferred to the Vanuatu Fisheries Department facilities in Port-Vila for experiments on their larvae (Dumas et al 2014). At Bunaken and Madang, reef surveys focused on habitat mapping, but benthic macro-species considered important for fisheries (e.g., sea cucumbers, giant clams) were counted and photographs taken.…”

Larval ecology of the fluted giant clam, Tridacna squamosa, and its potential effects on dispersal models

“…Waterborne cues released from adults could attract competent larvae to actively settle nearby (Braley, 1987;Ricard and Salvat, 1977). More recently, Dumas et al (2014) experimentally showed that 5-day old Tridacna maxima larvae exhibited significantly stronger swimming activity towards 5-month old conspecifics (representing 'favourable habitats'), compared to cyanobacteria mats (representing 'unfavourable' habitats). Coupled with existing giant clam population data, results of larva attraction to conspecifics are particularly useful when attempting to model patterns of settlement and recruitment, i.e., in areas where giant clams are present, it potentially increases the chances of successful larval settlement and recruitment.…”