be refined and modelled more extensively. Indeed, the next steps
consist in coupling the hydrodynamic larval dispersal model with
a larval bioenergetic growth model (Thomas et al., 2011b). The result
would be a model of larval dispersal taking into account currents
but also environmental and food conditions. Development
of a bioenergetic growth model is also planned for adults. A series
of experiments in Ahe Atoll planned in 2012–2013 will collect new
data to meet these goals, also using new methodological
approaches.
Another objective for French Polynesias is to expand the research
to other lagoons where natural spat collection occurs. A priority
is Mangareva Island in the Gambier Archipelago. Mangareva
consists of a large deep lagoon surrounding several small high islands
where black pearl farming is still active and productive.
On-going projects will investigate larval dispersal and Pinctada
margaritifera ecophysiology in very different environmental and
hydrodynamic conditions than those found in Ahe or Takapoto. It
is also planned to monitor occurrences of spawning events using
the condition index (ratio of wet weight of the visceral mass to
shell weight) (Le Moullac et al., 2012). Together, spawning monitoring
and larval dispersal modelling will enhance the accuracy
of the spat collecting forecast system that French Polynesia aimed
at.
All these future activities on Ahe and Mangareva are currently
planned in the POLYPERL (2012–2014) and BIODIPERL (2012–
2013) recently funded projects. Finally, we point out that the professionals
involved in pearl farming in the various atolls and islands
are generally supportive of research activities. Their
support is essential, and a great motivation, to conduct the researches
presented here elsewhere. Therefore, on the long run,
additional atolls should be studied, such as Arutua and Kaeuhi.
The modelling, environmental and ecophysiological work pioneered
in Ahe should provide for these atolls an objective foundation
to establish spatial zoning plans in their lagoons. For the
benefits of farmers, space and concessions would be allocated
according to the most optimal areas for collecting larvae, and for
growing juvenile oysters and grafted adults.