*2.1. Description of the Study Site and Sampling Points*

Nahoon beach and its canal are located in East London, Eastern Cape, South Africa on the coast of the Indian Ocean (geographical coordinates: 32.99◦ S and 27.95◦ E). As shown in Figure 1 below, the study area was in Buffalo City Metropolitan Municipality in the Eastern Cape, as highlighted in the map. The Nahoon canal is observed as an extension of the Nahoon River, which flows into the beach. A total of six sampling points for the beach and the canal (three points each) were mapped along the sea shore. Nahoon canal point 3 flowed into the Nahoon beach at point 1, and Nahoon canal point 2 had some domestic effluent flowing into it. There was a release of final effluent from the East Bank Reclamation Works (sited in East London, South Africa) into the Indian Ocean at Bats Cave, which is represented by sampling point 2 on the beach site in this study.

**Figure 1.** A map showing the location of the study area.
