Page 18 - UNEP_MAP2015

2.1 Topographic features of remarkable biological relevance

2.1.1 Banks, seamounts and submerged volcanoes

Seamounts are considered as highly productive and biodiversity hotspots, since they
produce retention areas for phytoplankton and create the conditions that support a diversity
of important habitat types. According to a very recent census of the banks, seamounts and
underwater volcanoes in the Sicily Channel carried out under the IUCN–MAVA
PROMETEOS project (PROtection of the MEdiTErranean Open Seas: Contributing to the
establishment of Marine Protected Areas over offshore seamounts and submarine canyons)
this area is featured by several structures that can be classified as seamounts according to
the definition given by Staudigel et al. (2010), who stressed that it is important to:

 Have a simple definition that explains which features are included under the umbrella
of seamount research and which are not, providing an essential condition for defining
the seamount research community,

 Respect and be aware of differences among disciplinary definitions, as they may
stand in the way of consistently applying one disciplinary data set to another.

Geoscientists define seamounts as constructional features, so that formation processes are
at the heart of their views and definition. Biologists define seamounts as habitats that are
controlled by specific ocean environments, including the shape and summit depth of the
feature studied.

Staudigel et al. (2010) have combined these diverse perspectives under one inclusive
umbrella definition that describes seamounts as: any geographically isolated topographic
feature on the seafloor taller than 100 m, including ones whose summit regions may
temporarily emerge above sea level, but not including features that are located on
continental shelves or that are part of other major landmasses.

According to this definition it is possible to identify at least 34 main structures of which it was
possible to find the official name (tab. 1) and at least 9 more, likely banks, seamounts or
volcanoes that have not been possible to find the name in the scientific literature or
elsewhere (tab. 2).

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