A Bottle Drifting in a Plastic Ocean


On November 5, the Bruce Museum will be hosting a free showing of the documentary film A Plastic Ocean at its Seaside Center (click here for more information). This documentary explores the causes and consequences of the proliferation of plastic in the oceans, but when I hear the title I am taken back to a time in my childhood.

While staying on the shore of the Chesapeake Bay, I wrote a letter, put it into a plastic water bottle, and tossed the bottle off the side of my grandfather’s boat. I was captivated by the idea that someone on a far distant shore might find my letter and know me through that connection. I left my name and address, hoping that whoever found it might write me someday.

In a seemingly miraculous stroke of luck, my letter was indeed discovered and read. A woman and her husband had found it on Assateague Island. We exchanged letters of introduction and continued being penpals for several years after.

Back then, throwing a message in a bottle into the water felt like an exciting journey into the unknown. Now, I think about that plastic bottle floating in the waters of my beloved bay and can only be grateful that someone was responsible enough to remove it. As illustrated in A Plastic Ocean, the more we learn about the amount and effects of plastic in the ocean, the more serious the situation appears.

It’s easy to generate trash and even easier to avoid thinking about what becomes of it. Of the things we throw away, plastic is one of the most ecologically harmful. 70 years ago, plastic was unheard of. Now, over 300 million tons of plastic is produced every year, approximately half of which is designed to be used once and then discarded. Yearly, about 8 million tons of discarded plastic ends up in the ocean. At our current rate of plastic dumping, by 2050 we will have more plastic in the ocean than fish.

So, if my message bottle hadn’t been discovered by a kindly couple in Assateague, what would have been its fate?

It takes around 450 years for a plastic bottle to completely break down in the ocean. My bottle might have drifted around until the year 2428. It wouldn’t have stayed in the Chesapeake Bay area for long either. Oceanic garbage doesn’t just float around at random. Currents move garbage in distinct patterns throughout the oceans and deposit large amounts of trash in areas of open water known as “garbage patches.” There are six garbage patches of ocean across the world. The Atlantic Ocean is home to one of them, and it probably would have been the eventual home to my water bottle.

Garbage patches usually form in the center of circulating oceanic currents, known as gyres.

Garbage patches usually form in the center of circulating oceanic currents, known as gyres.

Even if my bottle was stuck in the Atlantic garbage patch, it would have had a lot of space to roam. The patch spans an area roughly the distance between Cuba and Virginia. If you’re garbage, you’re in good company there. There can be as many as 520,000 bits of trash per square mile in the densest areas. However, for the most part, the garbage isn’t visible to the naked eye. Most of the garbage bits are smaller than 0.01 inch, plastic broken down into miniscule but long-lasting pieces. Many of these tiny bits are pushed down as far as 65 feet underwater, making them even less obvious to the casual observer.

Though humans might not notice tiny pieces of plastic, fish do. The plastic particles are virtually indistinguishable from ordinary plankton or other sea debris floating around. In a previous blog post discussing the ecology of the deep sea, I mentioned how plastic fibers had been discovered all the way down in deep sea communities. In an apparent case of mistaken food identity, many deep sea creatures were discovered to have ingested these small plastic fibers. This unfortunately only scratches the surface of the impact that plastic has on sea life. All sorts of organisms closer to the surface are now consuming plastic too. Small particles of plastic are eaten by filter feeders and other organisms that eat small matter, while larger animals accidentally eat the larger pieces of trash.

Recently, a dead sperm whale was discovered off the coast of Spain. It had over 37 pounds of greenhouse supplies in its stomach, including sheeting, rope, and flower pots. Manufactured substances like plastic are indigestible, so they just sit in the stomach of the whale, bird, or turtle that ate them. This can cause a cascade of ill effects ranging from starvation to stomach rupture.

This dead albatross chick's stomach is full of plastic fed to it by its parents.

This dead albatross chick's stomach is full of plastic fed to it by its parents.

There are many other well-loved sea species that now have plastic in their diets. Sea turtles who normally dine on jellyfish now eat buoyant or translucent plastics that resemble their gooey prey. Albatrosses have taken to swallowing debris as well. The famous Midway Atoll albatross nesting site sits in close proximity to the Great Pacific Garbage Patch. When albatrosses fly out to find food for their chicks, they find plastic instead 12% of the time. Young that consume too much garbage will die, leaving these long-lived but slow-reproducing birds in peril.

Garbage affects countless other species of fish, birds, and marine mammals. Animals can get entangled in discarded nets or fishing lines, or stuck in six pack rings. I’m glad that my plastic bottle isn’t one of the bits of trash harming all those animals, but there are many other plastic bottles that are.

In 2014, 100.7 billion plastic beverage bottles were sold in the United States alone. This averages out to 315 plastic beverage bottles per person per year. 14% of all litter is composed of plastic beverage containers and this number would be even higher if it included the caps and labels. In a stroke of bitter irony, not only do plastic water bottles generate garbage, they also waste a lot of water. The process involved in making a plastic water bottle uses six times more water than is actually in the container. For a container meant to hold water, plastic water bottles sure waste a lot of it.

Cutlery made from biodegradeable plastic.

Cutlery made from biodegradeable plastic.

So what is the fate of our plastic ocean? Even if we stopped all plastic production now, it would take hundreds of years for the oceans to clear. However, that doesn’t mean that it’s a lost cause. There are a number of labs researching biodegradable plastics made out of natural materials. Some countries have gone so far as to ban single-use plastic bags entirely in attempt to encourage sustainable plastic use. A widespread ban hasn’t yet caught on in the United States, though certain cities have begun taking more aggressive stances against them.

I fell into the bad habit of using disposable plastic water bottles after losing my metal one, but recently have made the switch to another reusable bottle instead. A single person cannot fix the entire plastic waste problem on their own, but there even small actions can someday add up to big change.

Want to learn more about oceanic plastics and how you can help? Attend our free showing of A Plastic Ocean on November 5, including comments from a local group attempting to reduce disposable plastic use.

- Kate Dzikiewicz, Paul Griswold Howes Fellow