SeaweedClick to go to the Seaweed page to learn more
Red TideOutbreaks of red tide along the South African coast are reported periodically in the media, with warnings to the public about the dangers of collecting and consuming shellfish in the affected areas. Most red tides represent useful contributions to plankton production but some periodically produce harmful results. The toxic or harmful algal blooms are normally restricted to the West Coast and it is unusual for red tide in False Bay to be harmful.
Red tides usually occur along the South African Cape west or south coasts in late summer and autumn. The prevailing southerly winds at this time of year cause cold, nutrient-rich water to rise up from the deeper regions of the ocean to the surface, a process known as upwelling. At night you will see the fluorescence in moving water - looks most spectacular as a wave breaks. Best seen on dark nights with little moon but as the photo below shows, if there is enough it is spectacular with the moon. Click to go to the Ecology and History page for scientific information on red tides |
Rooiels has wonderful rock pools rich with life -- sea urchins, little fish, rocks with a range of limpets and bright coloured seaweed. The photo on the left has Porphyra capensis - purple laver or better known as the Japanese cousin "nori" hanging on the rocks. You can eat this as is - very chewy style biltong - or you can bake it in a hot oven with a little oil and eat it like crisps!
Get a glimpse of what lies below our sea by going on a dive with Nico Kessop by linking to this u-tube video here.
A comprehensive overview of the ecology, fauna and flora of our estuary is given in the Estuaries report which you can download here - or see on the website here.
Seashells on the Rooiels seashore....
Your browser does not support viewing this document. Click here to download the document.
The Venus Ear or Siffie (Haliotis spadicea) normally around 40mm is one of the 5 abalone found in South Africa.
The much larger Perlemoen (Haliotis midae) which grows to 230mm can be found usually where poachers have been. Click to Learn More Dwaf Fan shells (Chlamys tincta ) These colourful little bivalves have a single fin at its base, where the larger Scallop (Pecten sulcicostatus) has 2 fins
|
DUNES
We are still working on this page -- please share any information you have on this and any other topics |
Plough shells (Bullia) Live Plough molluscs are usually found ploughing into the beach where the waves subside and some folks say they indicate safe swimming areas. Plough shells are like the hyenas of the ocean, quickly eating up any dead fish or jelly fish they find.
Marginellas are small and pretty gastropods with smooth, shiny shells and a strong, lipped aperture with 3-5 ridges on the inner lip. Baby’s toes (Trivia aperta) are cute, pink, cowrie-shaped shells with ridges running right over the shell. Violet shells (Janthina) are very fragile blue/purple shells Some 18 species of Limpets can be seen along our shores. Keyhole limpet shells have holes at their apex through which a syphon protrudes. Paper Nautilus (Argonauta argo) This is the egg case of an octopus-like cephalopod. Nautilus shells can be washed onto shore in winter but few survive the waves or seagulls!
Chitons. These molluscs create eight overlapping shell plates over their backs. Slow-moving creatures, they can often be seen sheltering under rocks in tidal pools. We have some 10 different species in our area.
Links to history, geology, and various issues related to seashore and marine environment |