https://theconversation.com/the-demand-for-luxury-shellfish-is-polluting-the-ocean-with-plastic-118668
[links and images in online article]
The demand for luxury shellfish is polluting the ocean with plastic
August 13, 2019 6.17pm EDT
Leah Bendell
Professor of Marine Conservation and Ecotoxicology, Simon Fraser University
The federal government has taken action recently to reduce the amount of
plastic waste found on land and in oceans, rivers and lakes.
In June, for example, it said it would ban single-use plastics by 2021.
“It is tough to explain to your children why dead whales are washing up
on our beaches with their stomachs jammed packed with plastic bags,”
Prime Minister Justin Trudeau commented at the time.
Despite this progress, one of the main plastic polluters — shellfish
aquaculture — continues to threaten marine ecosystems.
Coastal British Columbia is rugged and jagged. Its drowned fjords are
home to wild salmon and the ecosystems that depend on them. Tucked away
between Vancouver and Denman islands is Baynes Sound, a serene inland
sea, home to sea mammals, globally important duck and bird populations,
and a biological diversity unmatched along our coast.
So unique is this ecosystem that, 20 years ago, the Department of
Fisheries and Oceans (DFO) recommended regions within this area be set
aside as protected areas.
Threats to the sound include increased tourism, urbanization and
an-as-yet-unregulated seaweed harvest. The greatest threat, however, is
an expanding shellfish industry that provides a continual source of
plastics to the sound.
Shellfish aquaculture
For the past 14 years, community beach cleanups have measured the
plastic in Baynes Sound. An astonishing four to six tonnes of plastic
debris, including anti-predator netting, plastics trays, ropes and
styrofoam, is collected from the beaches annually. Now polyvinyl
chloride (PVC) piping, used for the farming of geoducks is also being
washed ashore.
In 2017, the DFO gave the West Coast shellfish industry a green light to
expand its farming practices to include the lucrative geoduck, a luxury
protein used in sashimi, to meet the demand from Hong Kong and the rest
of China.
Geoducks (pronounced “gooey ducks”) are large salt-water clams, found
naturally along the Pacific coast. Sales of farmed geoduck to this
select market netted close to $56 million in 2017.
Farming them involves placing juvenile geoducks into rows and rows of
18-inch long segments of PVC piping, planted vertically into the
intertidal sediments, at a density of one pipe per square foot. Nets are
secured with elastic bands over the pipe to protect the immature geoduck.
But the pipes become loose within days, especially after storm events,
and the beach becomes littered with the plastic netting, elastics and
pipes. Wave action and ultraviolet light from the sun degrade the pipes,
creating fragments and then microplastics (items smaller than five
millimetres in diametre) that further pollute the marine environment.
Ecosystem and health impacts
PVC is one of the most common plastic polymers in use, and its breakdown
can damage ecosystem and human health.
The particles may harm invertebrates, fish, seabirds and other organisms
that consume them. The chemicals in the plastic debris, including
plasticizers, phthalates, flame retardants and stabilizers, can leach
out of particles and have the potential to harm marine organisms.
Finally, the pipe fragments can also act as a substrate, providing
pathogenic marine organisms and parasites in near-shore environments
with a place to grow and multiply.
“Canadians know first-hand the impacts of plastic pollution, and are
tired of seeing their beaches, parks, streets and shorelines littered
with plastic waste,” Trudeau said in a statement after he announced the
single-use plastics ban.
“We have a responsibility to work with our partners to reduce
plastic pollution, protect the environment and create jobs and grow our
economy. We owe it to our kids to keep the environment clean and safe
for generations to come.”
So, why the paradox?
The government says it’s intent on protecting at least 10 per cent of
our coastal ecosystems and reducing the threat of plastics to our marine
environments. Yet the industry, which is managed by our federal
government, has been given permission to introduce hazardous plastics
into one of B.C.‘s most sensitive ecosystems.
The ban on plastic holds consumers accountable. It targets their
behaviour and will force change. But this is only part of the problem.
The other part of the problem is the industry practice of discharging
dangerous plastics into sensitive ecosystems. Government is regulating a
change in consumer behaviour. Why not do the same for industry?
If the government’s goal is to protect these sensitive marine
ecosystems, it needs to stop the flow of plastics from industrial
sources including the unregulated shellfish industry. The economic gain
of farming sashimi for a select market is not worth the environmental cost.
[Shelley McKeachie, a founding member, past chair and director of the
Association for Denman Island Marine Stewards, co-authored this article.]
=====================================
To subscribe, unsubscribe, turn vacation mode on or off,
or carry out other user-actions for this list, visit
https://www.freelists.org/list/keiths-list
Note: new climate change website is now in pre-launch
Visit https://www.10n10.ca/e/index.shtml