A follow up: The potential impacts of Red Swamp crayfish in Western Cape waters
Since first being found in the canal systems of lower Olifants River in 2022 by CapeNature officials, invasive Red Swamp Crayfish (Procambarus clarkii) are being found further afield in the Western Cape at an alarming rate. This freshwater species is globally recognised as a seriously damaging invasive species, having been introduced for aquaculture and the ornamental pet trade.
Red Swamp Crayfish are generally recognisable through their dark red colouring and S-shaped claws. However, many different colour morphs exist in the pet trade, and they may be white, blue, pink, bright red or brown. Continental Africa has no native crayfish, therefore the threat posed by this species is considerable as the fragile freshwater systems and species of the Western Cape are not adapted to crayfish.
Red Swamp crayfish
Crayfish are large bodied species which alter nutrient cycling through shredding organic matter and feeding across all trophic levels – including fish eggs, zooplankton, juvenile fish, amphibian larvae, macroinvertebrates, macrophytes and even each other. Invasion by crayfish has been linked to declines in popular recreational fisheries in Europe and they have the capacity to rewire entire ecologies when they establish. For example, amphibian tadpoles metamorphosise earlier in invaded locations to avoid predation and an increase in mosquito disease vectors is related to crayfish invasion as the risk of predation pressure reduces native dragonfly larvae consumption of mosquito larvae. Red Swamp Crayfish are also asymptomatic carriers of the water mould Aphanomyces astaci (“crayfish plague”) and the amphibian disease chytridiomycosis. They are burrowing species which destabilise riverbanks, cause damage to farming irrigation canals, and increase sedimentation.
It is essential that this species does not continue to establish in the Western Cape, as the ecosystem engineering capacity of Red Swamp Crayfish may alter the unique habitats permanently. Moreover, management of crayfish invasions is extremely costly. For example, in Canda, up to R2 billion / year is spent due to damage costs and control attempts for Red Swamp Crayfish. Please, do not breed, release or spread crayfish into the wild. Crayfish are extremely good escape artists and can survive out of water for up to 10 days if they stay wet enough. Please report any freshwater crayfish sightings to CapeNature (Dr Martine Jordaan, mjordaan@capenature.co.za) as soon as possible and catch any found in the wild.
Related News
Firefighters honoured after one of the Western Cape's toughest fire seasons
CapeNature hosted an appreciation event in Velddrif on 4 August 2026 to honour firefighters who were on the frontlines during the Western Cape's most recent fire season. A representative group attended the event on behalf of CapeNature's larger cohort of Field Rangers and firefighters working across the Province. Despite extreme heat and challenging terrain, the firefighters remained steadfast in their commitment to protecting communities, infrastructure and the Western Cape's
CapeNature welcomes the conviction of Cape Town couple for wildlife crime
CapeNature welcomes the sentence imposed by the Wynberg Magistrate’s Court on Mr Zirkie Bernardus Jansen and Mrs Valerie Gayle Simpson-Jansen of Kirstenhof following their conviction on multiple offences relating to the unlawful keeping, possession and transport of reptiles. The couple were each sentenced on 30 July 2026 to pay a fine of R40 000 or serve 18 months’ imprisonment after being convicted on seven counts under the Nature Conservation Ordinance 19 of 1974.
The joy of being outdoors
Life has a way of becoming busy, but sometimes the greatest luxury is simply slowing down. Imagine waking up to fresh mountain air, taking a gentle stroll beneath towering trees, listening to birdsong, or enjoying a quiet cup of coffee while overlooking breathtaking natural landscapes. These are the moments that help us reconnect with ourselves and appreciate the simple joys of life. We believe everyone deserves the opportunity to experience the restorative power of nature. That's why we're inviting senior citizens to enjoy peaceful escapes across the Western
Freshwater science takes centre stage at the 2026 SASAqS Conference
The Southern African Society of Aquatic Scientists (SASAqS) is a learned society concerned with the research, management and conservation of inland waters and their associated biota throughout southern Africa. Established in 1964 as the Limnological Society of South Africa, SASAqS provides an important forum for discussion and sharing of scientific ideas. The two cornerstones of the society's activities are the annual conference and the African Journal of Aquatic Science.
Marine Protected Areas hold the key to human wellbeing
On 1 August, we celebrate Marine Protected Areas (MPAs) Day, a global occasion first marked in 2021 to recognise the role that MPAs play in conserving our oceans while supporting the wellbeing of people and communities. The day encourages us to appreciate the value of MPAs and the many ways they benefit both us and the extraordinary marine biodiversity they are designed to protect. This year's theme, "Ocean Protection Needs Human Connection," reminds us that conserving our oceans is a shared responsibility.
Bringing Conservation to Life Through Storytelling, Film and Digital Media
When was the last time a film, photograph or story about nature made you stop and feel something? Perhaps it was a breathtaking wildlife documentary. A short social media reel that transported you to a mountain peak. A travel video that inspired your next adventure. Or a story that highlighted the impact of a wildfire and reminded you why conservation matters. Every adventure has a story. Watch ours on our YouTube channel and subscribe for more.