Think Out Loud

Project reveals new insights on how beach trash accumulates on Oregon, Washington shores

By Sheraz Sadiq (OPB)
Aug. 30, 2022 4:28 p.m.

Broadcast: Wednesday, Aug. 31

Marine scientists at the University of Washington have found patterns in how trash accumulates on beaches in Oregon and Washington, and differences in the kind of trash that’s washing up, depending on location. The scientists made their findings based on more than 800 beach surveys conducted from 2017 to 2021. The work was conducted by volunteers at the Coastal Observation and Seabird Survey Team, a citizen science program based at the University of Washington. The surveys revealed the existence of “sticky zones,” areas on a beach where both trash and natural debris such as seaweed tends to accumulate. Seasonal differences were also observed, with the highest amount of debris occurring in the spring and the lowest recorded during the fall. And while almost all of the trash that washed up on outer coastal beaches was made of plastic, about half the trash found on inland beaches was made of heavier materials like glass and metal. Jackie Lindsey is the science coordinator at the Coastal Observation and Seabird Survey Team. She joins us to talk about the findings and the impact they could have on coastal cleanup efforts.


The following transcript was created by a computer and edited by a volunteer:

Dave Miller: This is Think Out Loud on OPB, I’m Dave Miller. Marine Scientists at the University of Washington now have a better understanding of where and when and what kinds of trash are accumulating on beaches in Oregon and in Washington. They gained this knowledge with the help of a team of 280 volunteers who over the course of five years, regularly surveyed more than 60 beaches. Jackie Lindsey is a Science Coordinator at the Coastal Observation and Seabird Survey Team, or COSST, which is based at the University of Washington. She joins us now to talk about their team’s findings and the impact they could have on coastal cleanup efforts. Jackie Lindsey, welcome.

Jackie Lindsey: Hi, thanks so much for having me.

Miller: Thanks for joining us. Why did you want to do this particular project? But what were the big questions that you had?

Lindsey: Well, it goes back to the origins of our citizen science program in general, where the Coastal Observation and Seabird Survey Team and our origins are in beach surveys for washed up marine birds, which we use to monitor ecosystems. But we knew we wanted to study something else as well. And we really wanted to enable and encourage our own citizen scientists to find out more about what they were curious about in their marine environment as well as what we, the academic marine research community, were interested in. And we all agreed that marine debris, what washes up on our coastlines that’s not naturally occurring but created by humans, that’s a big area of interest for all of us.

Miller: Can you describe a typical survey that a volunteer did for this study?

Lindsey: Our participants go through pretty extensive training to be able to repeat really pretty rigorous survey methodology. And so they go out to the same beach area once every month. And they conduct a survey where they look for debris that’s between the size of their fingernail and the size of their forearm. That’s, that’s what we call medium sized debris. It’s not stuff that’s really really tiny on the beach and it’s not something that’s too big to pick up usually. So they go out and they survey some random positions on their beach looking for those trash items all along the beach transect, and then when they find something they don’t just say, ‘One, found, one piece of trash on the beach today,’ they actually look at that item and record a whole bunch of characteristics about it. What’s it made of? Does it have any beak marks on it that indicate a bird was trying to eat it? Is it floppy and loopy? Was it something that could have been an entanglement risk to an individual? So they don’t just record that trash was there, but they also record how much and what kinds of characteristics we could tie to impacts in the marine environment.

Miller: Why was it important to get all that data? I mean what did you do with it- before we get to where the trash ended up and the seasons, why did you want to know all those details about it?

Lindsey: It’s a lot to set up, I agree. And there’s lots of different things we can look at and think about when we talk about studying marine trash. But what we’re really curious about is where is that intersection between what we find on the beach and what the effect of that item is in the environment. So when we have people not just say I found one thing on the beach, we want to know maybe where that thing came from because there’s lots of people who are interested in cleaning up the trash on the beach or preventing it from washing up there in the first place. So a lot of our data is tied to those sort of purposes as well.

Miller: I imagine that your volunteers would throw out this trash after they logged it?

Lindsey: Oh yes. There would be a rebellion if we asked people to leave trash on the beaches. Absolutely not. Yesterday, they got rid of upwards of 10,000 pieces of debris just in the process of doing this exact research for our program.

Miller: And where exactly were these beach visits? These surveys being done?

Lindsey: Yeah. They were taking place all over a region of the state in Oregon that you’ll all be familiar with across Coos Bay, Newport, Tillamook, there are beach observers doing surveys.  We  also had participants surveying in Washington State along the outer coast and in the inside waters of Puget Sound. So we got the really cool contrast between beaches that are impacted by the ocean really directly on the outer coast of Oregon and Washington and beaches that are in more sheltered waters of Puget Sound, where there’s really high population centers as well.

Miller: What were the big differences in general between an outer ocean or beach that really just goes straight out to Asia, and an inner coastal beach, like the complicated Puget Sound?

Lindsey: In short, the differences between those two places are that the trash we see washing up seems to come from the people littering their own nest in Puget Sound and on the outer coast, it’s not necessarily trash that was deposited there by really local residents, trash may have washed in from a marine origin, which means it could have come from many thousands of miles away or maybe even just a couple of beaches away, but it’s washed in from the ocean rather than being deposited directly on shore.


Miller: How were the surveyors able to find out or ascertain that in the cases of Oregon beaches, say the ones that were really exposed to the entire ocean. That trash could have come from really far away?

Lindsey: We tried to get at this in a couple of different ways because it’s one of the things that we’re really most interested in: Where did this stuff come from? So we look at a couple of different things to try and tease it apart. And what we did in this particular study was to look at trash that is likely to float and travel long distances and what the characteristics of that are. And we used material as a proxy. So something that’s really light and floaty might be made of plastic, something like a concrete block or a brick that’s found on the beach is not likely to float around really easily driven by wind or waves. So when we see washing up on a beach, a really high proportion of these items, that are made of plastic or plastic fragments, that makes us think that that means the most of the trash that’s washing up on that beach is also able to travel from a really long ways away. So when we’re looking at inside waters of Puget Sound, in contrast to those outer Oregon beaches, we see much more debris that is made of those heavier materials like cement or glass or concrete that couldn’t really travel very far, very easily. And that’s a direct contrast to the objects on the outer Oregon coast where you might be walking along a stretch of beach and you find 10 items of debris, nine of those 10 items are going to be made of plastic.

Miller: You found that some areas of the coast are ‘stickier,’ that was the word that was used in the article, in the report, meaning that they’re more likely to accumulate trash, but also natural debris, like seaweed or driftwood. Why is that…why is it that that stuff accumulates more often in certain places?

Lindsey: It’s a great question and our study tried to make that very complex answer a little bit simple by looking at these sticky zones, but let me back up and talk about there are a couple of different factors that can affect how much stuff ends up washing up on a beach. One could be, if there’s just a lot of beach visitors, for example, bringing their picnics to that beach, they could also be incidentally bringing a lot of trash that escapes their pockets and their trash cans and it ends up on the beach…

[Voices overlap]

Miller: …Or intentionally leaving construction debris like pieces of concrete on Puget Sound, as you mentioned...

Lindsey: Or…exactly…it’s a, it’s not necessarily an accident. Sometimes it’s a dumping site that’s for the community in some way, you’re right. So that’s one way that we can see things washing up on the beach and that might happen more in high tourist seasons or in times of year when people are really trying to get rid of their stuff for whatever reason. But there are also these factors that are more tied to the sticky zone hypothesis that we were talking about – these factors, where the wind and the waves and the shape of the beach itself as well as its inclination, so its ‘C’ shaped or straight, is it really steep beach, or is it a wide, flat and sandy beach? Is it made of cobble or sand? All of those things worked together to determine not just how much trash comes into that beach, but how much stays there for you to find when you go walk that beach, you know, a couple hours later after it’s washed in. So you may have an impression of a beach as being really, really dirty at some times of year and really really clean at other times of year because all of those factors change season to season. And we did see that in our data set as well.

Miller: Your surveys took place from 2017 to 2021 which includes almost two pandemic years and the last part of that, did the amount or the kind of trash change over the course of that period?

Lindsey: In this particular study, we did see that we had a slight decrease in the amount of trash over that time period, that five year time period. And this in some senses could make us hopeful that maybe we’re getting less trash coming in from the ocean. There could be a couple of things tied to that and we’re not, we’re not 100% sure exactly why that might be, but one hypothesis could be that we are getting further and further away from the 2011 Japanese tsunami event, where a lot of debris was unintentionally released into the ocean and it has swirled around and been deposited on our coast coastlines in relatively large numbers since then. And that might be tapering off. So that’s just one possible hypothesis as to why we’re seeing an overall decrease on, on the outer coast. Inside waters, maybe there’s new policy and regulations that are going in that are having a greater effect than those seasonal changes at sea. And that could also be having an impact. But we’d want to look at it for a little bit longer to really say why. And if that’s a true trend that’s going to continue.

Miller: But the tsunami hypothesis is a really sobering one, because it’s just, it’s a reminder of how long some of these bits, especially very floaty plastic bits, can circulate in the ocean and eventually make their way thousands of miles away?

Lindsey: It is. And we have continuously seen much smaller spills from container ships and things like that where we know that a lot of material was dumped into the ocean at a particular point and on a particular date. And we can see those things washing up on our coastline, sort of impulses as we track those pulses in the ocean systems as well.

Miller: We have just about a minute left. How do you think your findings could affect coastal cleanup efforts going forward?

Lindsey: We have these data that we’re collecting and we’re continuing to collect, by the way, this process is ongoing, where we’re able to establish a baseline of how much trash is washing up on different regions along different coastlines. So if there are some of these, either container spills or policy changes and measures that we put into place to try and keep trash out of the ocean, we’re able to test ourselves, are we making an impact on how much is actually washing in our beaches after those policy changes go into effect. And that’s a really powerful tool to be able to say that what we’re doing is working, or not. And maybe we should try something else. So our efforts can help to tailor some of those cleanup and mitigation efforts directly.

Miller:  And the surveys are going to continue?

Lindsey: They will. We have surveyors probably out there this Labor Day weekend, in fact, who will be walking those coastlines and near Coos Bay or Newport. You might see them out there.

Miller: Jackie Lindsey, thanks very much.

Lindsey: Thank you so much.

Miller: Jackie Lindsey is a Science Coordinator at the Coastal Observation and Seabird Survey Team or COSST, which is a citizen science project based at the University of Washington. If you want to learn more about COSST and if you want to become a volunteer yourself on one of their marine debris surveys, you can go to []  COASST dot org .  Tomorrow on the show, First generation college students and new graduates entering the workforce might not be aware of certain unwritten rules. Helping them learn that information is what’s behind a new collaboration between Portland State University and the Portland Opportunities Industrialization Center. We are going to hear about this partnership on the next Think Out Loud. Finally, today we have a really bittersweet goodbye. The very first episode of Think Out Loud was in January of 2008; Julie Sabatier was there. Today, almost 15 years later, is her last day with us.  I could not count the number of guests that Julie booked or the segments that she rescued or pulled out of thin air or the shows that she directed or the trips we went on together. It is literally, literally, literally in the thousands. So much of what our show has been and what it is now, and what is going to continue to be is because of Julie’s smarts and creativity and her hard work and humor and good cheer and her Baltimore sass. She’s also been a kind of one person hard drive, a human repository of TOL Lore, who we’ve come to rely on to remind us what we’ve done because if Julie cannot remember it, it probably just didn’t happen. The sweet part of the bittersweet is that we’re not exactly losing Julie and nor are OPB listeners. Starting tomorrow Julie is going to be a full time Podcast Producer at OPB, making awesome, long, firm, long form stories that I cannot wait to hear. So on behalf of our whole team at Think Out Loud, Julie, congratulations, we love you and thank you. We’ll be back tomorrow.

Announcer: Think Out Loud is supported by Steve and Jan Oliver, the Rose E. Tucker Charitable Trust and Michael, Kristen, Andrew and Anna Kern.

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