St Helena Bay and Elandsbaai on the West Coast, are two of three areas affected by a red tide.
Authorities from the Department of Forestry, Fisheries and the Environment (DAFF) confirmed the red tide is confined to those areas.
The Department’s Zolile Nqayi, said confirmation followed evidence of satellite images and reports, from Elandsbaai to the Olifants Estuary on the West Coast.
That is where scores of shellfish, white mussels and whelks, washed out over the weekend.
Nqayi said there is also a visible red tide in Walker Bay, Hermanus, which is bioluminescent- turning into flashes of colour at night.
The Department also said fish kills in the Hartenbos estuary, on Sunday, are related to sewerage discharge and ammonia toxicity and not the red tide.
Picture: Supplied