We, the undersigned, are concerned citizens who recognize the importance of maintaining ecosystem integrity in freshwater and marine systems around the world. Sharks – as apex predators - are integral components of healthy ecosystems and the uncontrolled removal of these animals has been shown to have significant negative and long-term cascading effects on ecosystems.
Zambezi (bull) sharks, Carcharhinus leucas
, are considered apex predators. As such they represent an essential component in healthy marine and estuarine ecosystem functioning. There is little doubt the presence of this species in the Breede River – located on South Africa’s southwest coast - assists in maintaining a healthy ecosystem balance. Despite this, however, we are aware that Zambezi sharks are being systematically targeted and killed by anglers in the Breede River due to their perceived impact on fish populations in the system.
We are also aware that:
- as apex predators, Zambezi shark populations are naturally limited by the carrying capacity of their environment. Unnecessary and uncontrolled fishing mortality will result in significant population declines;
- Zambezi sharks are listed as a globally Near Threatened species by the IUCN Species Survival Commission;
- Zambezi sharks in South Africa appear to be experiencing localized population depletions due to fishing, habitat degradation and other human-induced impacts;
- the Breede River was only recently described as an important seasonal habitat for Zambezi sharks in South Africa. The location, temperature and physico-chemical characteristics of the system indicate this may be the most unique habitat for the species in southern Africa, and may require a complete revision of existing ecological and biological knowledge of the species on a global scale;
- evidence indicates the Breede River Zambezi sharks exhibit philopatry (homing) to the system. This means the sharks exert significant ecological influence on the river and their systematic removal through fishing will negatively impact riverine ecological functioning;
- evidence indicates the Breede River Zambezi sharks undertake trans-boundary migrations from South Africa to Mozambique. Although not regularly targeted by commercial fisheries in South Africa, the species is targeted for their fins and meat in Mozambique and are thus subjected to increased fishing mortality. This will negatively affect the abundance of a species listed as Near Threatened in South Africa.
Despite these facts, however, and an appeal to employ the precautionary approach to fisheries management in the Breede River until further ecological and behavioural research is conducted, no measures exist to mitigate the systematic removal of this keystone species from the river.
- the importance of Zambezi sharks in ensuring the maintenance of healthy marine and estuarine ecosystems, and
- the obligations of South Africa’s Department of Agriculture, Forestry and Fisheries (DAFF) and the Department of Environmental Affairs (DEA) to preserve and maintain the natural heritage of the country
We, the concerned citizens, urge DAFF and DEA to
- ban the targeting of
- fishing for
- wilful harm to
- and removal of
Zambezi (bull) sharks, Carcharhinus leucas, in the Breede River, South Africa.
Thank you for taking the time to read and consider this petition.