Chondrichthyans and MPAs
Marine Protected Areas (MPAs) are an important spatial planning tool and we are expecting a few changes in our existing MPA network in South Africa. By now most of us have heard of the South African government’s efforts to establish a network of 22 new Marine Protected Areas (MPAs) and thereby increasing the coverage from presently 0.5% to 5%. This endeavour is part of the government initiative “Operation Phakisa”, which aims to rapidly unlock the economic potential of South Africa’s marine environment and yet ensure the protection of ecologically significant habitats. At the same time there has been a heated discussion about last-year’s gazette on re-opening Africa’s oldest Marine Protected Area, the Tsitsikamma MPA, to recreational fishing.
MPAs also provide protection to sharks, batoids and chimaera. But the degree of protection is highly variable between species and mostly depends on their movement behaviour and distribution. For example highly migratory species will experience less protection, as they travel large distances along or away from the coastline and thus spend most of their time outside of protected areas. Species that are known to be highly migratory and require a different protection approach are listed in Annex I of the Memorandum of Understanding the Conservation of Migratory Sharks (MoU). The list includes the following South African species:
White shark (Carcharodon carcharias)
Whale shark (Rhincodon typus)
Basking shark (Cetorhinus maximus)
Shortfin mako shark (Isurus oxyrinchus)
Longfin mako shark (Isurus paucus)
Portbeagle (Lamna nasus)
White Shark in the Robberg MPA
Species with a strong site-fidelity like our endemic catsharks on the other hand can benefit greatly from MPAs. Yet according to the IUCN Redlist 46% of them are still listed as ‘threatened’ or ‘near threatened’. Our inadequate knowledge of their population structures has led to wrong assessments, in which species that were once considered widely distributed, such as the Puffadder Shyshark (Haploblepharus edwardsii), were revealed to having been commonly misidentified with similar species due to overlapping colour patterns. Consequently a species that was considered common and wide-spread is now known to have a very limited range and is listed as near threatened. Furthermore we know little about inshore-offshore movements of our catsharks – a vital piece of information for their protection. It is likely that catsharks represent an essential part of the bycatch in recreational fisheries, but there is little published evidence. We have started to actively search and collect photographs of stranded sharks, skates and rays to get a better understanding of the dimension of the discarded bycatch. The re-opening of protected inshore reef habitats to recreational angling like Tsitsikamma could also impact the resident catshark populations.
Please submit photographs of stranded sharks, skates or rays to email@example.com.
Escobar-Porras, J. 2009. Movement patterns and population dynamics for four catsharks endemic to South Africa. MSc thesis, Rhodes University, Grahamstown, South Africa, 81p.
Fowler S. 2014. THE CONSERVATION STATUS OF MIGRATORY SHARKS. UNEP/CMS Secretariat, Bonn, Germany. 30 pages
Knip DM, Heupel M, Simpfendorfer CA. 2012. Evaluating marine protected areas for the conservation of tropical coastal sharks. Biological Conservation 148: 200-209.
Mann, BQ. 2013. Southern African Marine Linefish Species Profiles. Special Publication, Oceanographic Research Institute, Durban 9.