In an interesting twist, research is now being conducted that looks at whether cable protection zones (CPZ) have a beneficial environmental effect by acting as quasi marine reserves.
The University of Auckland in collaboration with the Department of Conservation and Telecom New Zealand (TNZ) is investigating this possibility by determining if the CPZ contains larger fish populations than surrounding waters.
The pilot study, run by Auckland University’s Dr Nick Shears, is based on the Southern Cross Cable Network and PacRimEast landing corridor at Auckland, New Zealand.
Data is gathered via a baited underwater video system which involves lowering the video system to the seafloor on a tripod at stations located inside and outside the CPZ. Each station is occupied for 30 minutes and records the number of fish that try to feed. This video data is analysed in order to determine if there are any differences in the species, size and abundance of fish occupying the CPZ as compared to those outside of the CPZ boundaries.
Results from the inner Hauraki Gulf show little difference in snapper numbers between inside and outside the CPZ, however the seafloor in this area is very muddy and there is little bottom structure to attract fish. In contrast, in the outer Hauraki Gulf, there are large reef systems in the CPZ and the results are much more interesting. The video camera and diver surveys have shown good numbers of a variety of fish species thought to be attributable to areas of undamaged habitat. “We have been quite surprised at the diversity of species and abundance of fish at the reef sites within the CPZ. The diving is spectacular and we have seen large schools of Kingfish, golden snapper, tarakihi and many other species, which may not have been there without the CPZ” said Dr Shears.
“This was just a preliminary study and I believe that there is huge potential for this project” said Dr Shears. “If CPZ’s do in fact function like quasi marine reserves, then the benefits to our marine eco-system are significant. The percentage of the Hauraki Gulf effectively functioning as a marine reserve will increase from less than1% to around 5%”. Funding has been secured to continue this study in spring 2004.
Protection of the working cables has been of paramount concern throughout the course of the research. Both the Marine Safety Authority and TNZ have been involved to ensure that the cables were not at risk from any work associated with the study.
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