Some examples of the introduction and transfer of mollusc populations.
The Pacific oyster (Crassostrea gigas) and the Manila clam (Ruditapes philippinarum) are among the most significant examples of the introduction of non-indigenous species into new environments. The causes, conditions, results, and economic and biological repercussions of these examples are examined. The introduction of fish has been attempted for hundreds of species, whereas the introduction of molluscs has involved no more than a few dozen recorded species. With regard to the deliberate introduction of molluscs, none has led to significant ecological disruption; conversely this has led to the establishment of permanent coastal activities which do not greatly disturb the natural biotopes.