By: Purnille Albertyn
On the 17th and 18th of October, the Gouritz Cluster Biosphere Reserve (GCBR) team Jolandie Buck (Extension Officer), Nelisiwe Khusi (Hydrologist), Claude Schippers (Extension Officer), and Purnille Albertyn (Intern) went to Groenfontein Conservancy near Calitzdorp for a day of monitoring and data collection in preparation for the Conservancies Conservancy Day.
Conservancy background:
The Groenfontein Conservancy was initially established in 1998 and revived in 2025. The conservancy is defined as a group of like-minded landowners who have an agreement to cooperate towards the conservation of the environment on their combined properties (Conservancies in the Western Cape, n.d.). Groenfontein Conservancy is situated in the Klein Karoo northeast of Calitzdorp, situated within the Gouritz Cluster Biosphere Reserve. The perennial rivers found within this area are the Smits River, Klein-klaasriver and Nels River (G. Van Rensberg, personal communication, October 27, 2025). The water is used for farming, recreation and personal use. The vegetation types described for the area is Kango limestone renosterveld (Least threatened), Kango conglomerate fynbos (Least Concern), and Gamka arid thicket (Mucina et al., 2006). These diverse vegetation classifications provide the region with a variety of bulbs, succulents, trees, and fynbos species.
On the 17th, Nelisiwe conducted SASS 5 and Purnille assisted her, while Jolandie and Claude did general vegetation observation. SASS 5 (The South African Scoring System version 5) is a rapid bioassessment method for evaluating river health. It uses aquatic macroinvertebrates as bioindicators, different aquatic species, are given a score based on their sensitivity to pollution and habitat disturbances. The collected scores are used to calculate an overall index that indicates the ecological condition of the river.
What are Aquatic Macroinvertebrates?
Aquatic Macroinvertebrates are small organisms without a backbone that are visible to the naked eye and large enough to be easily collected. Analysing the aquatic macroinvertebrates in a waterbody/river can help recognise signs of ecosystems health.
The Aquatic Macroinvertebrates we found at the 4 sites are the following:
| Scientific Name | Common Name |
| HYDRACARINA | Water mites |
| EPHEMEROPTERA | Mayflies |
| ODONATA | Dragonflies and Damselflies |
| HEMIPTER | Bugs |
| TRICHOPTERA | Caddisflies |
| CASED CADDIS | Cased Caddis |
| COLEOPTERA | Beetles |
| DIPTERA | Flies |
| GASTROPODA | Snails |
| CRUSTACEA | Crustacea |
| TURBELLARIA | Flatworms |
SASS 5 was conducted at 4 sites within the Conservancy along the Smits River and Nels River. The water of all 4 sites was measured for clarity making use of a clarity tube with the results showing the water was clear and clean. A clarity tube is a citizen science tool which measures water clarity. Clarity in the rivers typically decreases with an increase in suspended solids. Observations with clarity levels of 50 cm or above are considered high clarity scores, while those below are considered low clarity. The sites we monitored had clarity scores over 50 cm, which is a good indicator of good water quality, low sediment disturbance, and a healthy river system.
The clear water made it easy for us to also carry out visual surveys and collect fish using the SASS 5 net. All fish species caught with the SASS 5 net were identified, counted, and returned to the sites collected. We identified three indigenous freshwater fish species during the survey: Galaxias zebratus (Cape Galaxias), Pseudobarbus tenuis (Slender redfin), and Sandelia capensis (Cape Kurper).
On the 18th, Jolandie did a presentation on the vegetation species that she and Claude found along the rivers. All plant species seen were photographed, identified and uploaded to iNaturalist (iNaturalist, n.d.). The conservancy has their own iNaturalist project which can be accessed by this link https://www.inaturalist.org/projects/groenfontein-conservancy.
409 different plant species have been uploaded into iNaturalist under the Groenfontein Conservancy project. There are 371 indigenous species listed on iNaturalist within the Groenfontein Conservancy area. 3 Species of this total have been recorded with assigned conservation status. Dioscorea hemicrypta (Near threatened), Psoralaa rubicunda (Critically rare), and Babiana karooica (Vulnerable).
There are 38 introduced or exotic species, currently listed within the Groenfontein Conservancy. These are species that were brought into the region for some historic purpose and has spread to be more common in the area. Not all these species are invasive species. Jolandie has also advised the landowners that attended the conservancy day on how to manage the invasive species in the conservancy.
After Jolandie did her presentation, Nelisiwe also did a presentation where she informed and explained to the landowners that attended, about the importance of maintaining healthy river systems to those in attendances. She has also conducted a miniSASS where she showed how the aquatic macroinvertebrates look like, and what it means if they find these aquatic macroinvertebrates in their rivers.
References:
Conservancies in the Western Cape. (n.d.). CapeNature. https://www.capenature.co.za/uploads/files/Conservancies.pdf
iNaturalist. (n.d.). iNaturalist. Retrieved November 30, 2025, from https://www.inaturalist.org/
Mucina, L., Rutherford, M. C., & Powrie, L. W. (2006). Vegetation Atlas of South Africa, Lesotho and Swaziland. The Vegetation of South Africa, Lesotho and Swaziland, 748–789.
Van Rensberg, G. (2025, October 27). Groenfontein Conservancy [Personal communication].