by Kyle Smith
Marine Ecologist, SAN Parks
Those of you who have at some stage either hiked the Otter trail or have previously been privileged to compete during the African Otter Trail run will know what I mean when I say that the Tsitsikamma coastline is truly spectacular. The sheer cliffs, lush green coastal forest, numerous forest streams, immense rock formations and the ever present crashing waves fill your senses leaving one feeling strangely punch drunk happy. I recently completed the Otter hike and by the fifth day I came to realise that although technical in some areas and thigh achingly steep in others the reason why the hike is set over five days is not because of distance, but, because you need time to assimilate all you see and hear. During our “take two” or “take five” rest breaks the minutes seemed to slip past in a silent and unnoticed cascade whilst we simply marvelled at all we could see.
During one of these breaks I started to think about an aspect to the Otter trail that one cannot see – life under the waves. For you see (or rather can’t see) the Otter trail runs along the shoreline of the oldest Marine Protected Area (MPA) in South Africa – the Tsitsikamma MPA. By adopting a degree of protection from stringent no-take to multiple use zonation, Marine Protected Areas enable natural ecosystem functioning through the protection of habitats and species. Established in 1964 the Tsitsikamma MPA was a first in Africa and is currently one of the largest MPA’s in the country. As a no-take reserve (no fishing, no bait collecting or removal of any organism being permitted) with a shoreline of 57km it currently protects 11 percent of the warm temperate south coast shoreline and adjacent shallow coastal reefs.
Historically MPA’s have generally been proclaimed as both a conservation and fishery management tool by protecting fish stocks and the habitats they utilise. A total of 202 species of fish, sharks and rays from 84 families have been recorded in the Tsitsikamma MPA. Fifteen of these species can be found on the IUCN (International Union for Conservation of Nature) red data list as either vulnerable or near threatened whilst many other fish species protected by the MPA are classified as over-exploited or collapsed in South Africa. By protecting populations of these species within MPA’s, over exploited populations outside the park boundaries would benefit through the movement of either adults or larval fish.
Research on many of the fish species caught by rod and reel (referred to as linefish) has shown that most of the historically important species populations are currently very low with some species numbers sitting well below 10 percent of pristine levels. In other words adult population numbers have decreased by over 90 percent for some species. Characteristics that make many of these fish susceptible to over fishing include, a slow growth rate, late to mature (breeding only occurring after three or more years), long life span (in excess of 20 years), a high degree of residency and complicated sex lives including age and size related sex changes. As an example Roman live on a small patch of reef (often less than 50m2), mature as females after 3 years and then change sex between 6 and 14 years of age to live the remainder of their lives (around 20 years) as males.
Comparisons between protected areas and adjacent open areas where fishing occurs highlights the differences in fish community structure. In general within an MPA there is a greater abundance and diversity of fish whilst the average fish size is larger. Research at Tsitsikamma has highlighted the benefit of the park to many fish species including roman, dageraad, red steenbras, musselcracker, blacktail, galjoen and carpenter. In some instances the abundance has been six times greater within the park compared to outside! The increase in fish size is also important for the simple reason that larger fish produce more eggs. From an ecosystem view Marine Protected Areas work and fulfil their function as both conservation and fishery management tools. However, the sustainability of our fish stocks will ultimately depend on fishing practices outside MPA borders and here consumers have a role to play.
Through our decisions those of us who eat seafood can have an impact on how our fisheries are managed. Firstly, we need to become informed as to what are the smart choices to make when eating fish – what fish should we avoid either because their numbers are very low or because the manner in which they are caught is ecologically destructive. The South African Sustainable Seafood Initiative (SASSI www.wwf.org.za/sassi) has developed a Consumer Seafood Pocket Guide which tells you which species are legal and more sustainable choices. Seafood species are rated as: i) Green – the most sustainable choices from the healthiest and well managed populations, ii) Orange – Think twice as there are reasons for concern either due to overfishing or the method of capture may cause severe environmental damage and/or has high bycatch or the species biology makes it particularly vulnerable to high fishing pressure and iii) Red – Don’t buy as they are either illegal to sell, the species populations have collapsed and/or there are extreme environmental concerns or there is inappropriate management. SASSI can give you the information to help guide your culinary fish experience but it ultimately relies on each and everyone of us to use the information and make responsible decisions. Should you be unsure of a fish species SASSI has a hotline number (079 499 8795) where you can text the name of the fish and the status will be sms’d back to you.
So for those of you who will be tackling the African Otter Trail run this year, enjoy it, take in the beauty of the Tsitsikamma coastline and whilst the muscles are burning listen to the ocean and spare a thought for the MPA you are running next to and the fish it protects.