A Study of 1,577 Pieces of Litter on Faial and Pico Traced Most of It to Lobster Boats in Maine

Researchers at Okeanos, the marine sciences institute of the Universidade dos Açores (University of the Azores), have put a return address on the plastic washing up on two Azorean islands. In a study announced this week and published in a Springer Nature journal, they logged 1,577 items of marine litter collected on the coasts of Faial and Pico, and found that most of it came off lobster boats working out of the north-eastern United States and Canada.

The material was overwhelmingly fishing gear: plastic components of lobster traps, principally escape vents and the identification tags that regulators require operators to attach to each trap. Those tags are what made the study possible. Where litter research normally deals in anonymous fragments, a trap tag carries stamped information about who set it and when.

"Materials associated with fishing, especially those bearing marks or identification codes, constitute a unique opportunity to establish a link between the waste found and the regions and activities that gave rise to it," said Christopher Pham, the study's principal investigator, who leads the marine litter group at Okeanos on Faial and has worked on the subject for more than a decade.

Sixty-three percent from the United States, three quarters of that from Maine

Reading the tags let the team pin down origins with a precision the researchers describe as rarely possible in marine litter work. Of the tags identified, 63 percent came from the United States, and 76 percent of those American tags originated in the state of Maine. The remainder came from Canada.

The dates were the second finding. Tags recovered on Faial and Pico carried dates ranging from 1983 to 2023, confirming that this kind of plastic can circulate in the ocean for four decades before coming ashore roughly 3,000 kilometres from where it was lost.

"The results of this study provide clear evidence of the cross-border nature of plastic pollution in the North Atlantic," said Yasmina Rodríguez, an Okeanos researcher and co-author. She framed the problem in terms island regions know well: they have to deal with marine waste generated far beyond their jurisdiction, over which local authorities have little or no ability to act at source.

What the researchers want done

The team proposes three measures: better marking and reporting systems for fishing gear, preventive steps to reduce plastic losses in the lobster fisheries of both the United States and Canada, and coordinated policy between the countries and regions involved.

The litter itself was not collected by a research vessel. It was gathered by former nature wardens of the Faial Natural Park and through a citizen science campaign run by Okeanos with local communities on Faial and Pico, which is how a decade of beach walks turns into a dataset.

The finding fits a broader picture already visible in Portuguese monitoring. National figures show that plastic accounts for nearly nine in ten items logged on Portugal's monitored beaches, and the Azores sit directly in the path of the North Atlantic Subtropical Gyre, which concentrates floating debris from both sides of the ocean.

What This Means for Expats

• This is not a local pollution story. The litter on these beaches is not being dropped by visitors or by Azorean fishermen. It is arriving on ocean currents from North America.
• Beach cleans have research value. The citizen science campaign behind this dataset is the reason the tags were catalogued rather than binned. If you take part in one in the Azores, the recording matters as much as the collecting.
• Expect this in policy arguments. Portugal's autonomous regions have long argued that they bear clean-up costs for pollution generated elsewhere. This study puts a state name and a date range on that claim.
• Faial and Pico are the sample, not the exception. The same currents reach the whole archipelago; these two islands are simply where the wardens and volunteers were walking.

Forty years is the number worth holding onto. A plastic tag clipped to a lobster trap off Maine in 1983 was still identifiable when someone picked it up on a beach in the mid-Atlantic. Whatever is being lost overboard this season will be somebody else's problem for a long time.