Water Quality Monitoring by CapeNature in the Cederberg Nature Reserve Complex
Animals and plants are used in science and monitoring as indicators of the health of an ecosystem, the so-called bio-indicators. In animals, both vertebrate and invertebrate species are used as bio-indicators. In rivers in South Africa, the established biological monitoring tool SASS 5 (or South African Scoring System version 5) uses macro-invertebrates (you can see them with the naked eye) to track water quality impacts.
This tool has been used to monitor river systems in CapeNature Protected Areas since at least the fourth version of this rapidly applied and cost-effective tool. One of the most recent surveys to use this tool, together with fish species sampling, was conducted in early December 2022. It was the freshwater system survey of the Cederberg Nature Reserve Complex. Staff from the regional and Nature Reserve office joined the CapeNature Fauna Ecologist for the region and the CapeNature Freshwater Ecologist for this survey. Sites were selected based on historical records of indigenous fish species' presence and whether there were any known impacts present. Sites are as far north as the Rondegat River, south as the Thee River, as far east as the Matjies River and as far west as the Heks River in the Cederberg Wilderness Area. Expectations were that most of the sites would be in at least a good, but preferably natural condition.
Results indicated a variation in river condition between sites. Based on the macro-invertebrate assemblages present. River condition in terms of water quality, varied from being modified (Driehoeks and Matjies river sites) to moderately modified (Breekkrans, Boskloof and upper Rondegat rivers), to good (lower Rondegat, Thee, Heks, Krom and Noordhoeks rivers).
The only site in a natural condition was on the Dwars River, despite the recent fire surrounding the area. The variation in the condition at these sites is quite surprising. It is expected that the patterns are mainly driven by the availability of habitat, where not all sites have a large enough variety of instream habitats. For example, the site on the Driehoeks River is mainly a pool habitat, which is not ideal for the SASS 5 method. However, the possible impacts on water quality observed during the survey included the, camping area (and its associated impacts) surrounding the upper Rondegat River site, the regular crossing of a herd of goats at the Breekkrans River site, the presence of invasive alien fish (bass species) in the Heks River and road crossings (bridges and causeways) at several sites.
These results support the importance of long-term monitoring to get a clear picture of variation in water quality and instream habitat diversity at least annually, but preferably on a seasonal basis.
Driehoeks River
SASS Tray at Heks River
Related News
A Win for Renosterveld Conservation as Haarwegskloof Declared a Provincial Nature Reserve
In a major victory for biodiversity conservation, Haarwegskloof, which includes the largest remaining connected stretch of renosterveld left on Earth has officially been declared a provincial nature reserve.
The reserve is owned by WWF South Africa and managed by the Overberg Renosterveld Trust (ORT), a non-profit organisation dedicated to protecting and restoring the fragile renosterveld ecosystem that once covered large parts of the Overberg.
Damara Trail Wins Silver Award at International Tourism Film Festival Africa 2025
CapeNature is proud to announce that its Damara Trail video series has won the Silver Award in the Tourism – Products category at the prestigious International Tourism Film Festival Africa (ITFFA) 2025.
CapeNature’s videos stood out for their compelling storytelling, visual excellence, and ability to capture the essence of nature-based tourism in the Western Cape.
“We are incredibly proud that the Damara Trail videos have been recognised on an international platform. This award helps to underline our commitment to sustainable tourism offerings. Much like the Damara Trail itself, the video helps to tell the unique history and story of the Waenhuiskrans area to visitors both far and near,” said Sheraaz Ismail, Executive Director: Eco-Tourism and Access.
Climbing in Rocklands this Season? Here’s What You Need to Know After the Cederberg Fire
The Cederberg, a protected wilderness area managed by CapeNature and home to some of the most iconic climbing and bouldering routes in South Africa, was recently impacted by a wildfire that began on 7 March 2025. The fire ignited near Krakadouw Peak and burned for 13 days, before being fully contained on 20 March. In total, it scorched 20,834 hectares, spanning 97 kilometers of fire line, and included damage to the Rocklands “Bouldering Area” — a popular climbing zone. As a result of the fire, several popular climbing sectors and access routes have been damaged or are temporarily inaccessible.
The Big Biodiversity Challenge is back – Learners Tackle Biodiversity Crisis in Provincial Competition
The Western Cape Environmental Education Friends (WCEEF), together with members CapeNature, SANBI, Nature Connect, SANParks, Working on Fire, the City of Cape Town, The Environmental Education Association of Southern Africa (EEASA) and the Two Oceans Aquarium, is thrilled to announce the return of its successful competition for children in grades 6 – 9.
CapeNature's vision - Protecting biodiversity for a sustainable future
Biodiversity forms the bedrock of life on Earth. It is essential not only for sustaining healthy ecosystems but also for ensuring human wellbeing. Last week, on 22 May, we celebrated International Day for Biological Diversity, to raise awareness, educate, and build understanding around biodiversity issues, while inspiring collective effort to conserve it for future generations.
Task team briefs Cape Peninsula Baboon Advisory Group on progress and way forward
The Cape Peninsula Baboon Management Joint Task Team (CPBMJTT) consisting of representatives from SANParks, CapeNature, and the City of Cape Town, hosted its second meeting with the Cape Peninsula Baboon Advisory Group (CPBAG) on 27 May 2025. The Shark Spotters who are implementing selected operational tasks under the banner of the Cape Baboon Partnership, also provided feedback on progress and challenges with the implementation of the Cape Peninsula Baboon Strategic Management Plan.
How can I assist you today?
How can I assist you today?