Pb. Mortensen et al., Distribution, abundance and size of Lophelia pertusa coral reefs in mid-Norway in relation to seabed characteristics, J MARINE BI, 81(4), 2001, pp. 581-597
Citations number
58
Categorie Soggetti
Aquatic Sciences
Journal title
JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM
This paper presents results on the distribution, abundance, and size of Lop
helia pertusa coral reefs in mid-Norway (62 degrees 30'-65 degrees 30'N) as
compiled from own investigations, earlier scientific reports, reports from
fishery surveys and fishermen. Detailed bathymetrical mapping covering an
area of similar to 600 km(2) along the Halten gas-pipeline, and two nearby
areas across the shelf revealed 70 Lophelia reefs. In general, the reefs oc
curred close to breaks and escarpments. High densities of up to nine reefs
per km(2) were found in areas with a rugged seabed topography and with a sl
ope >0.6 degrees. These seabed features have probably positive influence on
the transport and concentration of food particles and thus control the loc
al distribution of Lophelia. The area covered by individual reefs varied be
tween 1230 m(2) and 37,310 m(2) with a mean of 5628 m(2). The height of the
reefs was positively correlated with the area. Reefs < 10,000 m(2) had a c
ircular outline, while larger reefs were elongate, aligned parallel to the
depth contours. Along the pipeline the average density of Lophelia reefs wa
s 0.09 km(-2) which indicates that the total number of reefs is <similar to
>6300, covering similar to 35 km(2) within the whole study area.