In a campaign to gather information to protect marine biodiversity from the threat of plastic pollution, a team of eco volunteers from the Strandloper Project based in Sedgefield will be starting their third coastal research expedition hike on the 10th October.
Focused on mapping the distribution and densities of washed-up plastic pollution and fishing debris, the research team will be hiking 165km from Arniston to Hermanus. Complementing their 2019 and 2020 expeditions, they anticipate that data from the expedition will offer an insight into the type and origin of micro-plastic and plastic pollution along the southern shoreline of South Africa.
Having already surveyed 415km of coastline from Storms River Mouth to Blombos, on completion of the 2021 research expedition, the team will have surveyed approximately 19% of the South African coastline.
Along the coastal hike, they record valuable information about plastic pollution and washed-up fishing debris using 6 survey methods, all captured in an app called CyberTracker. From the previous two expeditions they have been able to demonstrate that over 90% of plastic pollution in the Southern Cape, especially micro plastics, are from inland sources, flowing down rivers and municipal infrastructure, like storm water drains and effluent outlets, into the ocean. As a result of lower rainfall in the recent drought cycle, when most rivers in the Southern Cape have been closed by a sandbar, they were even able to identify which rivers lose the most plastic into the ocean.
Mapping the distribution of washed-up fishing gear (trawl nets, longline ropes and crab pots) in relation to marine protected areas, the Strandloper Project has been able to show which MPA’s are targeted by commercial fishing activities, with unpatrolled MPA’s having the highest density of washed-up fishing debris, adding a possible threat to the marine biodiversity in the very areas proclaimed to protect them.
Expedition leader, Mark Dixon, is interested in the results from the upcoming expedition, particularly the area as they round Cape Agulhas. While the Southern Tip of Africa is considered to be the boundary between the warm Agulhas and Benguela currents, which may have an impact on the drift of plastic pollution before washing up, the Overberg and Whale Coast is also a region of longer rivers with multiple human settlements upstream, and increased population density compared to the Southern Cape. Both of these factors have a direct influence on the amount of plastic and micro plastic entering the ocean through rivers and coastal drainage infrastructure.
A large percentage of washed-up micro plastics are the result of plastic items being macerated by pumps in sewage and water treatment facilities and then being released into the ocean from municipal infrastructures. While difficult to quantify the impact of micro plastics on marine fauna, looking at the rescue and rehabilitation of stranded turtles by the Two Oceans Aquarium, over 90% of all turtles rescued defecate micro plastics in the first 24 hours during rehab. Micro-plastics and nurdles threaten the survival of marine fauna in multiple ways. Firstly, the presence of plastic items in the digestive tract may stimulate the sensation of a full stomach and inhibit the eating reflex. Micro-plastics are also a substrate for microorganisms to colonize, and when ingested by an animal, be a possible source of infection. Lastly, the chemical composition of the plastic could be toxic to some species.
Brenda Walters from the Dyer Island Conservation Trust has implemented some ground breaking work on testing and installing filters and barriers to reduce the loss of plastic from municipal infrastructure into the ocean and the Strandloper Project is excited to collaborate on the issue of plastic pollution with data from the expedition.
“The threat of plastic to marine life is overwhelming.” says Dixon. “While the public have the misconception that most plastic is ‘Ocean Plastic’, the reality is that the primary consumption and disposal of plastic products is by land-based populations. Until plastic consumption habits are modified, we have to continue to gather data that will assist in how the disposal thereof is better managed and how we can prevent it from flowing into the ocean.’
The Strandloper Project is reliant on donations to do the good work they do and to this end, have set up a Go Fund me platform for those who would like to assist with financial donations. GoGetFunding Crowdfunding Account
You can follow the Strandloper Project expedition progress and daily updates on their social media platforms on Facebook and Instagram.
To learn more about the Strandloper Project marine research and how you can support them, visit their website at www.strandloperproject.org