Splash! Trawling for microplastics on the Chesapeake Bay

Is there a connection between the plastic in our neighborhoods and the plastic thousands of miles across the sea?

This is the question that Trash Free Maryland set out to answer when it partnered with 5 Gyres to examine plastic pollution in the Chesapeake Bay.

For four days this month, they sailed around the bay, collecting water samples in multiple locations and in variable weather conditions.

I was thrilled to be invited aboard for one of the collection expeditions. On Friday, November 14, with an air temperature hovering at 40 degrees and winds at 25 knots, we sailed from Deale, Maryland toward the mouth of the South River in Anne Arundel County.

Along the way, we examined the samples from the previous two days’ trawls. The amount of visible plastic in the samples was striking – we could see a great deal of microplastics which were most likely photodegraded pieces of plastic bags or wrappers, along with pieces of fishing line and what was clearly the cellophane rip-strip from a pack of cigarettes. We were amazed that this stuff was collected from the surface of the water. We were only left to wonder what was suspended in the water column or snagged along the bottom.

When we reached our sampling destination everyone on the boat yelled “splash!” as the manta trawl, a custom-designed sampler that collects everything in the water except the water itself in an ultra-fine net, is tossed into the water. For an hour, the boat pulls the trawl, and then the crew hauls it aboard.

We placed everything that we collected in a labeled jar and visually inspected the samples. Then we sent them to a lab in Florida for scientific analysis.

The seas were very rough, so our samples were quite different than the previous days, which were calmer and warmer. Microplastics are neutrally buoyant, so choppy water churns them down the water column, far from the reach of the manta trawl.

What we found instead were mostly tiny pieces of polystyrene, which float to the top no matter the weather. These are ingested by marine life and, since they can’t be digested, will accumulate internally and often kill the animals.

This plastic in the Chesapeake Bay doesn’t just magically appear: it flows there from streams and rivers and, before that, streets and sidewalks.

Wondering what you can do to reduce the amount of plastic that ends up in our bay?

• First, reduce your consumption of disposable plastics. Shop with a reusable bag, carry a reusable fork and spoon to use when you eat out, and ditch the purchase of disposable individual water bottles.
• Second, recycle your plastics. And install a tight-fitting lid on your recycling bin so things won’t blow away and into storm drains or waterways.
• Third, spread the word! Tell others why you are so concerned about plastic pollution in your neighborhood, the Chesapeake Bay, and the world’s oceans. The holidays are coming up, and a reusable water bottle or bamboo utensil set makes a great stocking stuffer!
• Finally, support the work being done by non-profits like Blue Water Baltimore. Sign up for a cleanup, add your name to our mailing list, and donate if you can.

We all live upstream, and the best way to tackle the problem are to nix litter at its source. To learn more about the trash trawl project, check out our Storify thread.