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The Migrant Biota
5. Passive transport on ships or in ballast tanks has no relevance to the
problem of migration through canals. This is a process enhanced by human
navigation, with or without canals.
6. As every natural environmental phenomenon, canal migration is exposed
to severe restriction through danger of pollution. The prevalence of a limited
diversity of cosmopolitan pollution-resistant species in the world ocean will definitely be hastened by the existence of interoceanic canals.
7. Therefore, there is an added urgency for investigating interoceanic faunal
movements. Many opportunities, such as Lessepsian migration, have already
been lost, because of the lack of organized and cooperative research during the
different stages of a historical process. However, much like the danger facing
irreplaceable climax communities in the sea, the unique opportunities for studying contemporary models of big scale faunal replacements and readjustments
should be protected as much as possible from deleterious human interference.