Andrew Watts et al., ‘Through the sands of time: Beach litter trends from nine cleaned north Cornish beaches’, Environmental Pollution 228 (2017), 416-424.
The public is belatedly becoming aware of the growing pollution of the sea. While this has only forced its way onto the front pages over the past year or so, scientists have been aware of it for a lot longer. This article is based on a study of litter on beaches in north Cornwall.
It begins by pointing out that litter on beaches can come from the sea – from ships or fishing vessels, or from the land – from people visiting beaches, from rivers and sewage systems and the like. It restates the growing concern as thrown away plastic is ingested by fish and entangles marine wildlife, while noting studies that suggest beaches in ‘the south west’ are ‘amongst the most littered’ in the UK, the amount of this litter having increased by a fifth in two decades.
Managing and reducing the impact of litter requires a better understanding of the current trends and the sources of litter. However, it has been left to civil society to clear up the mess. This has been attempted through beach cleans. The authors describe the growing effort of volunteers as ‘fantastic’, but point out how it has not created a long-term data set on beach litter because of variability and uncertainty in the methods.
In contrast, this article reports on a six-year standardised series of beach cleans in north Cornwall. The collections were carried out from 2005 to 2011 by trained workers and funded by the former Cornwall County Council. They took place on nine beaches around Constantine Bay, the Camel estuary and Bude. Collections occurred in the first week of each month, cleaning 50 metres of beach each side of the main access point. The items collected were then categorised by type and source.
The 642 beach cleans resulted in 248,246 individual litter items. These were dominated by plastic, accounting for 89% of all items. Half the litter items were small plastic pieces. Even this underestimates the amount of plastic as it did not include microplastics less then 5mm in size. The sources of the items were fishing vessels (32%), beach visitors (19%), shipping, sewage and fly tipping (4%). But by far the biggest category was the ambiguous ‘unsourced’, which accounted for 46% of items.
The authors point out that different results in comparative studies can be explained by variations in how items are allocated. For example, a survey across UK beaches attributed twice as much litter to beach visitors. But that survey ascribed drink bottle tops (5% of all litter items in the Cornish study) to beach visitors. This article categorises them as ‘unsourced’, as most were weathered, indicating that they had been in the sea for an extended time and their source was therefore uncertain.
However, including plastic bags, drinks bottle caps and other plastic pieces in the ‘unsourced’ category will inevitably reduce the contribution of beach visitors and tourists. It’s surely more than likely that beach visitors contribute the majority of bottle tops washed up, rather than fishermen or people on ships. Indeed, overall, this study plays down the adverse effect of tourism. Although noting tourist-derived seasonal litter peaks, it describes the contribution of beach visitors as ‘only’ 18.7% ‘despite heavy use by tourism’. Yet this is low only because of the decision to allocate fragmented plastic pieces as ‘unsourced’.
Despite the article title, the six years of data does not tell us much about trends, which require a much longer dataset. Nevertheless, the article highlights the ‘astonishing amount of litter’ found on these beaches, despite the regular cleaning effort. It also highlights that around half of beach litter had spent an extended time in the sea before being deposited on the beach and picked up. ‘Floating plastic debris is accumulating off the coast’ and it warns that beach cleans only tackle the symptom of this rather than the source.
The article ends by suggesting some obvious policies – taxes on plastics, bottle refund schemes, education and regulations such as bans on microplastics. Yet it ends with a fairly vague call to ‘think about this problem more holistically’. Scientific studies like this identify the problem. It’s now up to social scientists to pinpoint who gains from continuing this environmental vandalism, why it’s taken politicians so long to deal with it and why people regard the oceans as a convenient dumping ground. Even this study took six years to be published. The plastics threat to our oceans demands a much greater level of urgency, both from academics and policy actors.