Living on the edge: the importance of monitoring rocky shores
While exploring our beautiful and rugged rocky shores, have you ever noticed bolts embedded in the rocks and wondered why they are there and what they do? Join me as I dive into the fascinating world of rocky shore monitoring—an essential project in safeguarding these dynamic coastal ecosystems.
South Africa’s coastline is enriched with a variety of coastal ecosystems, one of them being rocky shores. Rocky shore ecosystems on the west and east coast support a unique range of biodiversity (diversity of life) exposed to high levels of environmental variability. Over 24 hours, marine animals and plants on the rocky shores live in different zones that changes with the distance to the ocean. The amount of exposure to tides drives zones on the rocky shores – these range from being covered by seawater to being completely exposed to the sun. Resilient creatures have adapted to thrive in these conditions, asserting dominance within their zones.
However, South Africa’s rocky shores face threats such as pollution, climate change, invasive species, and overexploitation. These factors can disrupt the appearance and functionality of rocky shores, negatively affecting biodiversity, altering zonation patterns, and influencing social and economic aspects.
Marine protected areas (MPAs) fall within specific parts of the shoreline to safeguard these ecosystems. These areas protect vulnerable species and habitats, serve as educational and research resources, and mitigate global changes. However, how can we gauge if these MPAs are achieving their goals? Long-term monitoring steps in.
South African National Parks (SANParks), in collaboration with the Department of Forestry, Fisheries and the Environment (DFFE), have initiated comprehensive monitoring programs for rocky shores within national parks and MPAs. These programs entail dedicated sites monitored annually.
Selecting suitable sites involves zonation, wave exposure, and no-take or controlled zones. Each monitoring site comprises three transect lines, vertically dividing the rocky shore into low, mid, and high zones. Sites are chosen based on accessibility, clear zonation definitions, types of areas being compared, and avoiding rock pools and gullies. Suitable sites are marked using stainless steel bolts and recycled float fragments for easy identification, positioned 5 meters apart along each transect line.

Rushdi Ariefdien drilling to install permanent markers (Left). DFFE intern installing permanent marker (Middle). Example of permanent marker (Right).
After establishing these permanent sites, sampling commences. Using a reference tape measure, five images of a 30x30cm quadrat are captured between bolts. The goal is to observe changes over time. Counting and measuring harvested animals and their sizes are another aspect. Counts involve tallying creatures within a randomly placed 50x50cm quadrat, while measurements use specialized rulers.

An example of a 30 x 30 cm quadrat.
Consistent yearly sampling helps monitor changes, impacts of human activities, and the efficiency of MPAs. This practice improves ecosystem management strategies within MPAs, helping protect ecological communities and observe changes. So next time you are exploring our beautiful diverse rocky shores and find one of our sites, take a picture, tag us on our social media page and do not forget to spread ocean conservation awareness!