Dramatic Changes On The Banks Of The Bot River Estuary

It’s amazing to see the changes that have taken place in the last six months, on the the Bot River Estuary.

Everywhere the banks of the estuary are taking on a more beach-like appearance. On clean white sand, sea shells, sea weed, red-bait and cuttlefish are in evidence. The water tastes salty and it’s not unusual to see large shoals of tiny fish being preyed upon by diving sea birds, kestrels and duikers.

Bot River Estuary
Looking North over the Bot River Estuary, the renowned Arabella Estate is visible at centre on the opposite bank. In the middle distance, just left of centre, a group of four pelicans is feeding in the shallows — click to enlarge.

In the middle of August 2012, the mouth of the Bot River Estuary was artificially breached. This was done after consulting with the Bot River Estuary Forum (BREF), and estuarine specialists.

The water level of the Bot River Estuary was at its highest in many years, approximately 3 meters above mean sea level. Consequently, when the mouth was opened, the fast flow facilitated a deep scouring of the bed at the mouth.

When the mouth is opened, the water levels drop dramatically — to about 20 centimetres above sea level within a matter of hours. Over time the Bot River Estuary gradually becomes more saline as the tidal surge periodically brings fresh sea water into the system.

The estuary mouth has now remained open for an extended period; at this point 7 months and counting. With each passing month, the beauty of a true estuarine system is gradually unfolding (Flickr slideshow).

Four pelicans
Four pelicans feeding in the shallows — click any image to enlarge


estuarine vegetation 1
Beach pumpkin or seepampoen Arctotheca populifolia is found in deep sand on coastal dunes and around estuaries

Estuarine vegetation
This green spikey example of estuarine vegetation is a semi-succulent plant type and is a recent arrival on the banks of the estuary


Sandy shores and sea weed
Sandy shores and sea weed are in evidence on the banks of the estuary — click any image to enlarge


Typical tidal debris
Typical tidal debris that is found in healthy estuarine systems

Cuttlefish skeleton
Cuttlefish skeletons are commonly found lying on the tidal high-water mark


Red bait or rooi aas
Pyura stolonifera, commonly known in South Africa as red bait or rooi aas

The sandy bottom is clean
The sandy bottom is clean, and the water is saline and crystal clear



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