OVER the past decade or so there has been increased awareness in the broader community of the fact that everything that is dumped in our waterways and oceans does not simply disappear. In today’s world, with human populations continuing to increase exponentially, out of sight can no longer be considered out of mind. Recent media attention relating to the so-called Great Pacific Garbage Patch over an area of 1.6 million square km in the north Pacific Ocean between California and Hawaii, shows the situation with plastic is one case in point.
Recent studies of the garbage patch, which has been described by Australian media as “the size of Queensland”, has shown that it increased in area in recent years, which is not surprising given the fact that the plastics involved are not biodegradable. The expansion of the affected area is thought to be due in part to the large Japanese tsunami in 2011, and indeed around 60% of the plastic is of Japanese or Chinese origin. Around 46% of the weight of the plastic was comprised of fishing nets, traps or FADs, while an additional 10-20% was mixed debris from the Japanese tsunami in 2011. While the weight of the plastic that scientists have estimated occurs in the area seems large (at least 79,000 tonnes, possibly as low as 45,000 or as high as 129,000 tonnes), 79,000 tonnes of plastic in an area of 1.6 million square km of ocean, means that plastic makes up on average less than 0.000005% of the weight/volume of the top 1 meter of water in that region. While a concern, this is hardly the catastrophic situation some media outlets have portrayed it to be, especially when compared to the pollution issues (plastic or otherwise) regularly observed in rivers, estuaries and bays throughout much of the world, including Australia.
Examples of plastic problems that are not only more serious, but closer to home, include footage of divers swimming amongst a sea of plastic in Bali, pollution of beaches near Port Stephens from debris arising from containers lost by international shipping, and other recent reports relating to the deaths of seabirds, turtles and other marine fauna through plastic ingestion. A prime example was the recent death of a pilot whale in Thailand, which was thought to be due to the 80 large plastic bags it had in its stomach (not including the 5 bags that it regurgitated in front of rescuers as it died).
The immediate solution is, of course, simple, and has been demonstrated for nearly 3 decades by the actions of people such as yachtsman Ian Kiernan (who founded Clean Up Australia Day in 1989). Dispose of all rubbish into designated bins, and pick up rubbish left by other people who are less thoughtful and do not “do the right thing”. If rubbish is discarded properly, it will not end up in waterways defiling the view and endangering wildlife. But, of course, the root of the problem is the discarding in the first place. This means that reuse and recycling of plastic items needs to increase, as is being encouraged by recent moves by some state governments, such as Queensland, to implement bans on single use plastic bags and increase recycling of plastic bottles (encouraged by refunds of up to 10 cents per bottle).
Technology may also be coming to the rescue in the form of better biodegradable plastics. A great example of this is use of biodegradable 6-pack rings by certain environmentally friendly beer manufacturers such as The Saltwater Brewery in the USA. Pictures of their Screaming Reels IPA with the biodegradable 6-pack rings developed by US-based packaging company E6PR are sure to tempt anglers to switch over to what is obviously a fish friendly drop. Not only is it a savvy marketing ploy, the biodegradable polymer used to hold the 6-packs together is entirely compostable in landfill, and its biodegradable underwater. Being based on a starch polymer developed from waste from production of wheat and barley, the plastic is also non-toxic (and actually provides limited nutrition) to any wildlife that may eat it. While biodegradable plastics are a great advancement, they currently form a tiny percentage of total plastic production, and the risk with these sorts of technologies is that even more people may see them as an excuse not to “do the right thing” with their rubbish. Which, of course, is rubbish behaviour.
There is no denying that, with the world moving inexorably towards 9 billion people in the next couple of decades, the overall impact of plastics on our waterways and oceans is increasing. Unfortunately, the attention plastic is receiving is out of proportion to its actual environmental impact. Environmental scientists know that plastic is not (and never has been) the biggest pollution problem our waterways face. Indeed, pollution from runoff from urban and agricultural areas and nutrients, endocrine disruptors and pharmaceuticals from sewerage disposal represent a much larger (though largely invisible) threat to the health of aquatic environments in general, and fish and our fisheries in particular. The one thing plastic pollution does have going for it is that people can see it. It’s also actually the easiest of these aquatic pollution problems to solve. So by all means let’s get onto solving the plastic problem. But fishers should also use plastic as a “visible tracer” to highlight more important pollution problems that are currently out of sight, and therefore out of the minds of the wider community.
For more on the research into the Great Pacific Garbage Patch, see this paper, and for more on biodegradable 6 pack rings, click HERE.
Increased use of biodegradable plastics such as this starch based 6 pack holder from E6PR can help reduce plastic waste problems in our waterways and oceans. But we must remember there are more important (though less visible) aquatic pollution problems to address.
