Up to 15 million tons of trash slips into our oceans every year, endangering the marine mammals, fish, seabirds and sea turtles that may eat the rubbish, get entangled in it or be affected by endocrine disruptors.

Although scientists are skeptical about the feasibility of cleaning up the ocean’s gigantic floating garbage patches, a small Maine organization is attempting to rid the seas of trash. Instead of tackling the ocean’s far-off gyres of rubbish, however, Rozalia Project is trying to prevent trash from entering the ocean in the first place. Most marine debris moves into the marine environment from beaches, harbors and tidal rivers.

This summer, a Bowdoin alumna joined the Rozalia Project, sailing with the organization on its 60-foot boat, American Promise. Hannah Tennent graduated from Bowdoin in May with an earth and oceanographic science major. With free time before starting a 10-month post in September with the Student Conservation Association, Tennent took a temporary position with the ocean-cleaning nonprofit.

“My real passion is working with the environment, especially in conservation, and trying to protect and preserve the environment,” Tennent said. “What drew me to this [internship] was it was so interactive. I think the work all nonprofits do is important, but a lot of it is office work. This is science, in the ocean and on a boat. I was drawn to the action of it.”

Rozalia Project travels the Gulf of Maine, cleaning up local garbage patches and staging beach clean-ups and advocacy events. Offering on-board technology such as a multibeam imaging sonar, American Promise also hosts scientists whose research focuses on the impacts of humans on the marine environment. “We try to be an advocate and educate people, and do a lot of science to back up our advocacy and have the data to show people what’s going on out there,” Tennent explained.

One of the dangers of littering the ocean, particularly with plastic, is that plastic breaks into microscopic particles eaten by fish. Microbeads, small plastic particles in exfoliants and soaps, are also hazardous. “The danger there is it will travel up the food chain,” and affect humans, Tennent said.

Rozalia Project is also experimenting with innovative ways to clean up marine trash, such as using its remote-controlled robot to grab trash from the seabed, or a specially-designed net that leaves behind organic material while removing garbage from the ocean surface.

When Tennent climbed on board American Promise in July, she joined a crew made up of Miller, two guest scientists, three interns and Miller’s two Newfoundland dogs. They took off from Kittery (where they did a beach clean-up) and sailed to Portland, Boothbay, and Vinalhaven. In Boothbay and Vinalhaven, they met with locals to talk about our polluted oceans and what people can do to help. “Yes, we need to be cleaning the whole ocean,” Tennent said, “but I think it is easier and more effective to pick up bottles on beaches or on docks, before they get to the ocean. The average person can pick up four pieces of trash when walking his or her dog.”

Plus, you never know what kind of surprises you’ll find. Along with the 3,000-plus piece of trash Tennent and her team picked up along a Maine island’s beaches one day, Tennent found a wad of cash under a rock. When she counted it, she had $80 in hand.