Cold-water coral reefs - WWF UK

Cold-water coral reefs
7. Gaps in scientific knowledge
The previous chapters briefly summarized our current
knowledge of cold-water coral ecosystems and also
highlighted gaps in scientific understanding. Filling these
gaps is of crucial importance, in particular:
❏ Understanding the biological and ecological processes
and interactions of cold-water corals, the
associated species diversity and environmental
regulating factors.
❏ Ensuring that cold-water corals are not damaged or
destroyed accidentally, and enabling society to make
choices on conservation and exploitation.
When cold-water corals became a major international
research topic in the past decade, scientists needed a
forum to discuss their results within the steadily growing
community interested in cold-water corals, including
political bodies and environmental associations. The
International Deep Sea Coral Symposium series starting
in 2000 in Halifax, Canada, and continuing in 2003 in
Erlangen, Germany, has helped to meet this need. The
third symposium is to be held in the United States in 2005.
These symposia are supplemented by thematic
workshops and the publication of their proceedings
(Willison et al., 2001; Watling and Risk, 2002; Freiwald and
Roberts, in press). In addition, interim workshops
organized by NOAA and the Irish Marine Institute have
brought together leading scientists from the United
States and Europe to identify scientific research needs
(McDonough and Puglise, 2003). Based upon these expert
meetings, scientists have identified broad areas of work,
which require multidisciplinary efforts, to improve the
understanding of the ecosystem.
❏ Mapping: Using multibeam and other technologies
to develop low-resolution maps covering large areas
for identifying potential locations of cold-water
corals, and to develop high-resolution maps for
areas where corals are known to exist. Using still
cameras and voucher specimens to ground-truth the
bathymetric data and to develop habitat characterization
maps.
❏ Oceanographic data: Collecting high-quality oceanographic
data in order to improve knowledge of the
physical factors that affect the distribution and extent
of cold-water coral habitats.
❏ Geology and geomorphology: Collecting data on the
underlying geology of cold-water coral habitats, as
well as on their morphology. Using this information to
enhance understanding of colonization, reef succession,
recolonization after physical damage, and for
better understanding the habitat preferences of
selected species.
❏ Biology and physiology: Collecting and analysing
specimens in order to better understand coral species
and their genetics, to better characterize symbiotic
relationships, and to understand more about their life
history.
❏ Ecology: Collecting data on use made by other species
of cold-water coral habitats in order to understand
their wider importance.
❏ Human activities: Collecting information on human
activities that may harm cold-water coral habitats in
order to be able to better manage those activities.
❏ Socio-economic data: Collecting information to
understand the interconnectedness of cold-water
corals and human livelihoods.
❏ Time-series data: Collecting standardized data over
long periods to help identify changes in habitat over
time.
It is clear that there is a significant need to build an
information base on the growing body of research into
cold-water corals. A basic task is to locate and map
further areas of cold-water coral habitat to complement
existing information on their distribution, to understand
patterns of occurrence around the world, and to provide
location and extent information towards protection of
reef areas from damaging activities. The integration of
data sets into a GIS environment is essential to synthesize
this information. We already have some information on
the physico-chemical requirements for cold-water coral
reefs to develop, as a start to looking at where they are
likely to occur worldwide (water temperature 4-13°C,
some elevation or increased current, availability of
nutrients).
As research and surveying in deep and often
distant waters is very expensive, a modelling approach to
narrow down the areas to target with more detailed
mapping will be essential, particularly for high seas areas
and areas far from land. Such target areas could then be
surveyed using low-resolution multibeam survey to cover
larger seabed areas. High-resolution mapping with sonar
can then be undertaken for potential coral habitats,
together with optical tools such as towed or mobile
camera systems (ROVs, autonomous underwater vehicles
(AUVs), manned submersibles) to confirm the presence
and nature of the reefs identified. These data would not
only provide information on the presence or absence of
corals and associated megafauna, but also on the seabed
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