Browsing by Author "Ryan, P.G."

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    An Analysis of Beach Debris Accumulation in Table Bay, Cape Town, South Africa
    (1995) Swanepoel, Deborah; Ryan, P.G.
    Two sites in Table Bay, South Africa, were examined for stranded debris between October and December 1994. One beach (Milnerton) is a popular recreation area in the metropolitan area whereas the other (Koeberg) is closed to public access. Daily and weekly accumulation rates were measured for both sites. A total of 40 041 items were collected, of which 81.7 % was plastic. Half of this was styrofoam. The majority of the debris was related to floating recreational litter, packaging material and polystyrene trays. Indications of increased inputs during the peak holiday season were recorded at the public beach (Milnerton). Locale was found to influence debris abundance and relative composition. Within-site variation was great, and longer sampling periods are necessary to overcome this variability. Daily and weekly sampling intervals were compared; weekly sampling yielded relatively lower totals and weights of articles than daily intervals. Total article weights were positively correlated to total article number. There were few foreign articles and articles supporting epiphytic marine organisms. Most persistent litter washed ashore, but appeared to derive from local, land-based sources. Daily accumulation rates were generally not correlated to weather conditions.
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    The Prince Edward Islands Millennium Expedition: News and views
    (Academy of Science of South Africa (ASSAf), 2003) Crawford, R.J.M.; Underhill, L.G.; Bester, M.N.; Cooper, J.; Greyling, M.D.; Petersen, S.L.; Ryan, P.G.; Wilkinson, W.
    An expedition to survey bird and seal populations on the Prince Edward Islands took place from 11 to 31 December 2001. The first priority was to undertake a count of the breeding birds during the peak of the summer breeding season. An additional objective was to obtain estimates of the numbers of fur seals (Arctocephalus species) breeding at Prince Edward Island.