An Analysis of Beach Debris Accumulation in Table Bay, Cape Town, South Africa

Abstract

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 maj ority 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.