Detailed visual seabed survey at drilling site 7218/11-1
Detailed visual seabed survey at drilling site 7218/11-1
Detailed visual seabed survey at drilling site 7218/11-1
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Somespongesform densereefs,and providehabit<strong>at</strong> for a wide rangeof organisms,in a similarway<br />
to coralreefs(seeBuhl-Mortensenet al.2010).<br />
Figure13. Left: unidentifiedspongefrom the deep-w<strong>at</strong>er licenseBønna,home to a popul<strong>at</strong>ion of gammarid<br />
crustaceansand Right: a Geodia colony, offering substr<strong>at</strong>e and shelter for other organisms.Photo left:<br />
Akvaplan-niva/Oceaneering/Eni right: Illustr<strong>at</strong>ionphotograph,unknownloc<strong>at</strong>ion.<br />
All spongesgive habit<strong>at</strong> to other organisms,but the ecosystemimplic<strong>at</strong>ionsvary with scale.Small,<br />
individualspongecoloniesare hometo mainlysmallinvertebr<strong>at</strong>esand bacteria,whereaslargereefformingspongescanoffer<br />
protection alsoto largerinvertebr<strong>at</strong>esandfish.<br />
3.4 Red-listed sponges<br />
The Norwegianred-list for species(Artsd<strong>at</strong>abanken,2010) lists one sponge,Geodiasimplicissima<br />
underc<strong>at</strong>egoryDD(d<strong>at</strong>adeficient).Listedin termsof countiesin Norway,there are no spongeslisted<br />
asbeingthre<strong>at</strong>enedor in declinein northern Norway(Table2).<br />
Table2. Extractfrom Table8 in Kålåset al., 2010.Countydistribution of the numberof thre<strong>at</strong>enedand near<br />
thre<strong>at</strong>ened speciesbased on d<strong>at</strong>a from the Rødlisted<strong>at</strong>abase,and concernsknown current occurrencesor<br />
assumedcurrentoccurrencesbasedon earlierobserv<strong>at</strong>ions.<br />
Akvaplan-niva AS, 9296 Tromsø<br />
18 www.akvaplan.niva.no
Change language