Anton Dohrn Seamount and East Rockall Bank (2009)
Commissioned by JNCC, the surveys were undertaken by the
British Geological Survey, University of Plymouth and Marin
Mättenik AB. Its key objective was to acquire high quality
acoustic and photographic “ground-truthing” data to enable the
distribution, extent and biological characterisation of Annex I
reef within both AoS.
Anton Dohrn Seamount
This survey acquired 215 line kilometres of multibeam
echosounder data and 10 photographic “ground-truthing” sites
targeted within Anton Dohrn Seamount AoS.
Although data is still being analysed and interpreted, initial
observations revealed the flanks and area immediately adjacent to
Anton Dohrn Seamount to comprise predominantly gravel-rich sediment
with bedrock outcropping on the steeper sections of the seamount
flanks. Interestingly, the parasitic cones surveyed within the
Anton Dohrn Seamount AoS comprised predominantly corals, including
large gorgonian species, small bamboo coral, the soft coral
Anthomastus sp. and the antipatharian Leiopathes
sp.
This video footage shows some of the life that we found living
on the parasitic cones and "flies through" some of the multibeam
bathymetry data to show the shape of the seafloor around these
cones. Multibeam data sourced from SEA
7 (© DTI, 2005), MESH geophysical survey (© Wallis, 2006)
and JNCC (© JNCC, 2009). Seabed imagery © JNCC
East Rockall Bank
Within East Rockall Bank AoS, 692 line kilometres of multibeam
echosounder and 168 line kilometres of sidescan sonar data were
acquired.
17 photographic “ground-truthing” sites were also targeted.
Initial observations indicate East Rockall Bank to comprise
predominantly gravelly muddy sand on the eastern flank of the Bank
with gravel- and sand-rich sediments dominating the crest of the
Bank. Significant bedrock reef was encountered along an escarpment
located on the eastern flank of Rockall Bank roughly coincident
with the 500m bathymetric contour. This laterally extensive feature
primarily comprises volcanic bedrock with possible sedimentary
bedrock cropping out at sea bed colonised by large stylsaterid
hydrocorals and sponges.
Preliminary observations and
interpretation of the data acquired during the course of this
cruise suggest that several sites at both AoS may fit the
definition of Annex I reef under the EC
Habitats Directive. Once reporting is completed (end March
2010), the sites will undergo assessment against site selection criteria for possible
consideration as SACs.
The cruise report available below summarises operations and
initial observations onboard the M/V Franklin during
cruise 2009/03-JNCC on behalf of JNCC.
Further Reading
- Stewart, H., Davies, J., Long, D., Strömberg, H. & Hitchen,
K. 2009. JNCC Offshore Natura Survey: Anton Dohrn
Seamount and East Rockall Bank. 2009/03-JNCC Cruise
Report. Report No. CR/09/113.
Project Partners
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work then please contact us