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
Roll-out of baboon-proof bins to start as northern fence gets under way
The Cape Peninsula Baboon Management Joint Task Team is pleased to announce key developments related to the practical implementation of the approved Cape Peninsula Baboon Strategic Management Plan (CPBSMP). The Action Plan that guides the practical implementation of the CPBSMP was approved by SANParks, CapeNature, and the City of Cape Town in November 2025.
Explore the Western Cape for free this Access Week – Nature is for Everyone
A week of free access to some of the Western Cape’s most spectacular natural spaces is on offer this September, as CapeNature opens the gates to selected nature reserves for its 12th annual Access Week. Taking place from 19–25 September 2026 under the theme “Nature is for Everyone”, Access Week invites individuals, families and communities to explore participating reserves without paying a conservation entry fee.
CapeNature extends cashless payments to more nature reserves
Building on the success of its initial rollout, CapeNature will extend its cashless payment system to a further five nature reserves in September 2026, in line with its ongoing commitment to service excellence, sustainability and safety. Following the successful transition to cashless payments at Robberg, Keurbooms, Stony Point, Bird Island and Walker Bay nature reserves earlier this year, CapeNature will expand the cashless payment system to reach more visitors across the Western Cape.
CapeNature updates fees for commercial filming across its reserves
From fynbos-covered mountains and indigenous forests to rugged coastlines and Marine Protected Areas, CapeNature’s reserves have long provided a diverse backdrop for local and international film and television productions. From 1 October 2026, CapeNature is updating its commercial filming tariff structure to better align fees with the scale of productions and the demands they place on protected area management.
Western Cape communities called to join the 2026 #DontBeTrashy Drive
CapeNature in collaboration with the Department of Environmental Affairs and Development Planning is calling on communities, schools, businesses and visitors across the Western Cape to take part in the annual #DontBeTrashy Drive, running from 1—30 September 2026. The month-long campaign aims to reduce waste, protect biodiversity and raise public awareness about the growing impact of pollution on the Province’s land, rivers
Stony Point workshops equip tour guides to deliver informed and responsible eco-tourism experiences
CapeNature has brought tour guides and tourism operators together at Stony Point Nature Reserve to strengthen their knowledge of the site and support more informed and responsible visitor experiences. The first-ever CapeNature tour guide and operator workshops were held at Stony Point on 26 and 27 August, covering the reserve’s history, biodiversity, African Penguin colony, conservation work, and