Minerals Report - International Seabed Authority

cultivating sulphide oxidising bacteria inside their plume. He further stated
that the tubeworms draw hydrogen sulphide (H2S) through red plumes; the
red colour coming from the haemoglobin, the same as found in human blood.
Effectively, he continued, the tubeworms draw hydrogen sulphide into their
gut where they have colonies of bacteria that react with carbon dioxide to fix
organic carbon, producing foodstuffs for them to live on.
Dr German pointed out that no one expected to find these life forms
when they were first discovered in the 1970s in the Pacific Ocean. Their
significance he also said is that they actually produce a base of a food chain on
the seafloor that is independent of sunlight. In the Atlantic Ocean, he referred
to shrimp that are found at black smoker hydrothermal fields. He said that
each shrimp is about as long as a finger, maybe just a few centimetres long,
but because the shrimp are found in large quantities, it’s a different way of
accumulating huge biomass at any one site. At any hydrothermal field, he
noted there is very low biodiversity. He emphasized that at any field, while
there isn’t a huge range of species there are species that have adapted and that
cope with these environments, proliferating in their present state in huge
abundances.
Turning his attention to the mid-ocean ridges, Dr German said that the
mid-ocean ridges were the driving forces of plate tectonics in every major
ocean basin. The whole chain, he noted, starts in the Arctic Ocean and extends
through the Atlantic Ocean, the Indian Ocean out to the Pacific Ocean, about
60,000 kilometres of almost one continuous geologic feature. He also said that
the mid-ocean ridge system is not only the largest single geologic feature on
the earth but that it might also be the largest ecosystem. Through
biogeography he further noted, while scientists can determine that different
species live in different parts of the system, they still do not know what lives
in most of the world’s ocean basins and hydrothermal sites, because they
haven’t been to these areas to look for the associated biodiversity.
Dr German informed participants that when he started working in this
field there were only two known hydrothermal sites: the site at the northerneast
Pacific rise and the site at the Galapagos rift. He also informed
participants that the prevailing scientific theory until the early 1980s was that
hydrothermal activity occurred only on fast spreading ridges. In this regard,
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