The sampling frame - The quadrat. In the background - the antenna
tower.
Due to limited time and resources it was decided to use quadrate sampling, as we estimated the above limitations would have less effect on a small isolated sampling area like the shipwreck. Inter-specific relationships and competition also reduced with size and age of the settling corals. A sunken vessel differs from a natural reef site as the surfaces are generally flat and smooth. A vessel is small, confined and can be only compared to a similar vessel positioned close by.
Four preliminary dives supplied information which helped us decide on the distribution of the quadrates on the wreck surfaces. They were distributed to scatter the sampling evenly. The quadrate areas were marked and numbered with epoxy glue at the top right corner of the quadrate. The markings are permanent and allow for future monitoring. The sampling area was then photographed from 60cm, which aided the size and coverage calculations. It was also aimed to help with the inter-specific relationships and distribution of species on the more crowded samples. Later, most colonies were photographed in close up with a macro lens supplying 1:1.5 scale photos. Initial identification of the colonies was done on the shore, using the close up photos, then counting and measuring was completed under water.
All observations were done by scuba diving and assisted by one or two other divers
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