| Summary: | Maintenance and Update Frequency: notPlanned Statement: Initial transect survey (further details can be found in Section 3 of preliminary report) Knowledge of the vegetation, substrate and urchin density distributions at the this site was required before the pilot study was to proceed. The site were divided into equidistant sections. These have been marked with numbered boards at the site to enable re-location. Transects were run perpendicular to the shore at each of these marks. The transect line consisted of a lOOm length of 7mm rope marked every meter with lead 'net' weights and canvas 'flags' every 5 meters with the distance inscribed. Using a meter length of PVC pipe, urchins were counted for five meter lengths of the transect line within a distance of a meter from the line. Two divers were used for each transect. The divers did alternate 5 meter sections contiguously. Diver 1 (principal investigator) used a 0.25m2 quadrat, laid at each 10m mark (always starting from '0') to record vegetation cover. The quadrat was divided by seven lines running horizontally and vertically giving 49 intersection points. These and one of the corners gave 50. Substrate was divided into Reef, Boulders (0.5 1.0m diam.), Rocks (0.1-0.5m diam.), Rubble (0.02-0.lm diam.), Sand and Shells. Algae were divided into species as best as possible underwater. Algal cover and substrate were given a reading based on the number of points intersected. Total cover for algae can come to a number greater than 50 due to successive layers of algae. Recordings were made only for the extent of hard substrate as urchins are not generally not found on sand. Main survey (further details can be found in section 4 of main report) Initial clearings at Hope Island resulted in little recovery of macroalgal vegetation. This indicated that intended clearings of urchins at this site to improve roe quality would be unlikely to succeed. It was postulated that limpets may be an additional herbivore controlling vegetation so manipulations were conducted of ...
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