Minerals Report - International Seabed Authority

global mid-ocean ridge system. He pointed out that as vent sites become the
focus of mineral exploration and deep-sea mining, it would become necessary
to develop mitigative measures to avoid significant loss of habitat or
extinction of populations. In his presentation he gave a technical overview of
vent biology and ecology. Dr. Juniper stated that high animal densities and
the presence of unusual species are now known to be common characteristics
of deep-sea hydrothermal vents in the world’s oceans, with the composition
of fauna varying between sites and regions. He noted that deep-sea
hydrothermal vents occupy very small areas of the seafloor and many sites
contain animal species found nowhere else.
He pointed out that since the discovery of hydrothermal vent
communities, several interesting questions have been raised by biologists
regarding vent colonization, community survival in extreme conditions, and
gene flow along the global ridge system. Dr. Juniper informed participants
that the results of studies indicate that most hydrothermal vent species
colonise new sites by producing larvae, that are transported by ocean
currents. He stated that as gene flow is maintained through the exchange of
larvae, the populations and assemblages of species would continue to
resemble each other. New techniques in molecular technology are being used
to study this subject.
He stated that more vent species have been discovered on the
northeastern Pacific rise than on any other spreading ridge, because of a
longer history of research in this area, and the area’s relation with seafloor
spreading. In this regard, he pointed out that the significant archetypical
organisms (tubeworms) of vents in the eastern Pacific were conspicuously
absent from the known vent sites in the Mid-Atlantic Ridge. He noted that
seafloor eruptions provoke rapid and significant changes in the location and
style of venting and said that the biological consequences of perturbation of
the hydrothermal systems are considerable. He pointed out that active
hydrothermal vents are extremely dynamic environments and studies of how
vent communities respond to local environmental change could provide an
appreciation of their capacity to recover from human perturbations.
Dr. Juniper said that global hydrothermal vent faunas are one of the
most unusually adapted assemblages of organisms found in the oceans.
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