A sunny autumn day on the Island of Jersey and the beaches are thriving with people. Today isn’t just about enjoying the coast. Organised by Littlefeet Environmental - a non-profit that specializes in marine turtle conservation, ecology, and community development, 11 beaches and one underwater site across the Island are being cleaned by teams of volunteers.
“Every year tens of thousands of seabirds, marine mammals, and sea turtles are impacted by marine litter”, Littlefeet director Andy Farmer explains. “We are trying to do our bit to take whatever we can out of the water to reduce this impact… Jersey does not see many sea turtles, but because of tidal action, currents, winds etc., our litter can impact on marine animals across the ocean”.
Littlefeet aren’t the only ones cleaning beaches this weekend. Every year in September the International Coastal Cleanup, a collaborative initiative run by The Ocean Conservancy, enlists some 650,000 volunteers across the 90 countries to make the World a little cleaner. In 2013 some 5.6 million kilograms of litter was removed from nearly 21,000 kilometres of coastline. Some of the items collected are certainly unexpected, like dishwashers or voodoo dolls. The top three items, however, are all too familiar. Over 2 million cigarette butts, nearly 1.7 million food wrappers, and some 940,000 plastic beverage wrappers. This is just the litter we can see. The more we look at the ocean, the more we find, including in places we may not expect.
Using video footage captured by remotely operated vehicles in the Monterey Canyon, Kyra Schlining, senior research technician at Monterey Bay Aquarium Research Institute, revealed a host of debris down to depths of 3,971 meters - included one plastic garden chair some 3,962 meters below the surface, 300 miles offshore. In the Arctic, marine biologists Dr Melanie Bergmann and Dr Michael Klages of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association report that litter around the deep-sea observatory HAUSGARTEN has more than doubled since 2002. Accumulating in the North Pacific Subtropical Gyre, the Great Pacific Garbage patch, primarily consisting of small fragments of litter, some of which cannot be seen with the naked eye, is arguably the poster child of the pelagic marine litter crisis, though similar patches can be found at all the major ocean gyres. Marine litter isn’t just unsightly, it is detrimental to marine ecosystem health.
Some of the impacts are plain to see. Entanglement - often in, but not limited to in fishing gear, is a global issue. In December 2010 Eg 3911 - a two year old female North Atlantic right whale was discovered entangled in fishing gear off the coast of Florida in an emaciated state. Monitoring the whale with a Dtag during and after near-complete disentanglement, marine biologist Dr Julie van der Hoop of the Woods Hole Oceanographic Institution was able to reveal just how the whale’s ability to feed, dive, and migrate was hindered.
Eg 3911 was found dead just a few weeks after the final disentanglement attempt, most likely from exhaustion caused by dragging the fishing gear behind her. Ingestion of litter has been directly linked to mortality in a number of species, including green turtles and albatross which either it cannot tell the difference between litter and its prey, or are unable to differentially feed and thus avoid the litter when consuming its prey. With no nutritional value and a seeming inability to pass litter easily, starvation is inevitable.
Plastics and foams pose a particular problem for marine ecosystems. Few plastics fully mineralise in the ocean, instead breaking down to smaller and smaller pieces over a long period of time. Designed to degrade on land, biodegradable and bio-based plastics are equally poor at degradation in the ocean. These synthetic materials contain a range of toxins including endocrine disruptors and suspected carcinogens, such as PAHs, PCBs, DDTs, and BpAs. As conservationist Almira Van and colleagues from San Diego State University demonstrated in 2011, size is no barrier to toxicity, with plastic and foam pieces than 50 mm still retaining their toxic components. In 2013 Dr Chelsea Rochman, currently researching with NOAA’s Marine Debris Program at UC Davis explained that in water, the oily nature of plastic results in their compounds attracting to each other, increasing the toxicity of plastic pieces. These toxins can leach into the water, raising concerns that low-flow waters, like rock pools and marshes may potentially accumulate toxins and thus become hazardous to aquatic life.
Toxins also impact aquatic life when is consumed. In a separate piece of research, Dr Rochman fed Japanese with fish food that also contained 10% low-density polyethylene (LDPE). After just two months of exposure, the fish fed the plastic mix showed signs of liver stress, whereas the control group - which received no plastic in their diet - had no such problems. Because plastics merely break down into smaller pieces, litter can be small enough to be consumed by those sitting at the bottom of the food chain – the zooplankton.
The impacts of plastics on zooplankton - as for all marine species - remains poorly understood but, as demonstrated in a study lead by Dr Matthew Cole of Plymouth Marine Labs, it seems that the problems may not just lie with their toxicity. Some copepod species (small crustaceans) were found to ingest polystyrene beads just 1.7–30.6 μm in size. Although some of these microplastics were egested in faecal pellets, the impacts of consumption – if any – remain unknown. More clear-cut was the problem of microplastics sticking to the copepod’s external carapace, with one species of copepod suffering significantly decreased feeding as a result.
The potential impacts of toxins within an individual animal don’t stay with that individual. It is the fate of many an individual to be eaten by something else. When individuals holding toxic loads in their bodies are themselves consumed, toxins are passed onto and crucially tend to concentrate within the predator, which in turn is consumed by something else, and so on through the food web. As a result species nearer the top of the food web tend to contain higher concentrations of toxins than those near the bottom. There are concerns that cetacean females may pass on their toxic loads to their offspring through their milk, and that we humans – an apex predator that particularly enjoys eating marine species at the top end of the marine food web – could suffer reduced health as a result of seafood consumption.
The need to reduce the marine litter problem is increasingly gathering momentum in the public sphere. In the UK, the Marine Conservation Society lead campaigns to reduce plastic waste entering the ocean. The ‘Don’t Let Go’ campaign, for example, aims to reduce balloon and lantern releases, comparing these activities to littering by noting that what goes up must come down. The Society also host coastal and underwater cleanups throughout the UK and the Channel Islands. Alongside coastal clean-ups, there are a number of ocean cleanup initiatives currently in development.
Most recently entrepreneur Boyan Slat has raised someU$2 million from crowdfunding to construct and test a large scale operational pilot of The Ocean Cleanup Array – a floating barrier that catches and concentrates debris in gyres to allow the litter to be extracted easily. Unfortunately there is no easy fix to the litter problem, and it is perhaps unrealistic to think that we can remove all litter from the marine environment.
There will always be waste issues, but ultimately we – both individuals and governments - need to reduce the amount of waste we generate, and do what we can to prevent what we do generate entering the oceans in the first place. AsCaptain Charlie Moore, founder of the Algalita Marine Research Foundation told author Donovan Holm for his book ‘Moby Duck’, ”We say we’re throwing stuff away, but there is no away. The ocean is away”.
This story was published in The Marine Professional - a publication of the Institute of Marine Engineering, Science & Technology (IMarEST).