Why we're rubbish at caring for the sea

FINE LIFE: Waitemata Harbour is one of the most popular places to live in New Zealand.
FINE LIFE: Waitemata Harbour is one of the most popular places to live in New Zealand.

Over the past 10 years, Hayden Smith has collected three million litres of rubbish from Auckland's Waitemata Harbour.

His work for the Watercare Harbour Clean-Up Trust involves 160 hours a month on the water clearing trash.

“It's coming from so many directions," he said. "Parking tickets blown out windows, dogs attacking rubbish bags, recycling bins blown over and, of course, the cigarette butts.”

It all ends up in the sea, and the rubbish is starting to affect our marine life.

“About 45 per cent of the turtles that I do a post-mortem on have some form of marine debris,” said Dan Godoy, a PhD student at the Coastal-Marine Research Group of Massey University.

“But this is the first time we have been able to identify New Zealand packaging and products - chip packets, supermarket shopping bags, New Zealand beer packaging.”

Eating trash, which animals cannot distinguish from food, can block their intestinal passage and lead to a painful death.

Godoy's research focuses on turtles but the effects of rubbish on marine ecosystems is vast.

Plastic is the main culprit and biggest concern. It is an efficient absorbent of the ocean's pollutants - so much so, it is used to soak up oil after a spill.

But rogue plastic marine debris will also absorb the waste in the ocean, such as the coolant chemical PCB, and, when eaten by fish and marine life, accelerates the entry of chemicals into our food supply, with drastic results.

American oceanographer Charles Moore has spent the the past 13 years documenting the size and effects of marine debris pollution. He discovered the “great Pacific garbage patch”, a giant swill of rubbish converging in the northern Pacific.

“We found 35 per cent of the fish we caught out in the middle of the ocean had on average two pieces of plastic in them,” Moore said during his Auckland stopover to raise awareness of Pacific pollution.

Marine biologist and orca specialist Ingrid Visser says their populations around New Zealand are stagnant because of the chemicals being ingested by the prey.

In Greenland, the local Inughuit people are suffering from high levels of mercury and PCB, a result of eating fish and animals with high levels of ingested chemicals.

Now their women have been advised to stop breastfeeding as the level of chemicals in their milk is potentially toxic.

“The Inughuit are the sentinels for our species,” said Moore, who warned that plastic debris would affect New Zealand's fisheries, tourism and property prices.

The shipwrecked Rena not only dumped oil in Tauranga's ocean but also container loads of small plastic pellets, the raw material used to make plastic products.

Many washed up on the beach but many more are still at sea absorbing the Rena's pollutants and being consumed by marine life because of their similarity to fish eggs.

“We don't consider plastic as serious threat like we do oil," said Moore.

"But plastic is just the solid phase of oil. It is a way of making oil solid and last longer. Island nations are the first to feel it and I am trying to wake people up to how drastic the situation is.”

The impact of consumer rubbish on marine environments is the focus of a nationwide campaign being launched next week by Auckland-based charity Sustainable Coastlines.

“Essentially we end up eating our own rubbish,” said Camden Howitt, the organisation's communications manager. “You wouldn't bury rubbish in your vegetable garden, yet every day we pump vast amounts of litter into the feeding grounds of our seafood.”

The charity is advocating a simple solution: “Reduce the amount of waste we create and what we must use, dispose of it properly."

Sunday Star Times