Marine Debris

COASST marine debris participants conduct monthly surveys, collecting data on the characteristics and location of small, medium, and/or large marine debris objects on beaches from northern California to Alaska. As part of their involvement, participants learn about the sources and potential impacts of marine debris.

To get involved in our marine debris module:

  • Sign-up and attend a 6-hour training session in your community. See our training calendar for upcoming events.
  • Sign the COASST contract, agreeing to survey the beach of your choice every month.
  • Submit a $20 refundable deposit for the marine debris survey toolkit.
  • Grab a partner and head out to the beach to survey! You can choose to sample small and medium debris and/or large debris.

What's involved in a survey?

COASST Marine Debris participation is definitely a commitment!  Plan on 2-5 hours per month to survey your section of beach. There are three types of surveys for marine debris (small, medium and large), and participants have the option of doing one, two or all three.

Large Debris
For large debris surveys, the entire beach area is searched, from the surfline up to five meters into the vegetation.  For wide beaches, searching needs to happen on the way out (from start point to turnaround point) and also on the way back, to be sure to cover the entire width of the beach.  You and your partner(s) will space yourselves out to cover as much ground as possible, and walk in a slow S-shaped pattern down the beach, looking right and left for large marine debris (items greater than 50cm long).

Once found, characterizing and photographing large debris may take 1-3 minutes, depending on whether or not it contains information about where it came from or other important details.

Medium and Small Debris
For medium and small debris surveys, the beach is sampled in 3-5 randomly located sections of the beach. Medium debris (items between 2.5 and 50cm) is sampled in 5m wide rectangles that run from the back of the beach to the water’s edge. Small debris (items less than 2.5cm and greater than 2.5mm) is sampled using a sampling square (provided by COASST) adjacent to the randomly located rectangles. Samples of medium and small debris can be characterized and photographed on or off the beach.

The total amount of time spent surveying will be variable depending on the width and length of your beach, the number of surveyors, the weather, the survey type (small, medium, or large debris), whether or not you photograph and characterize debris on or off site, and - of course - how much debris you find.

COASST records the total time you and your partner(s) spend surveying the beach to get accurate information on survey effort.  Using this information, we calculate debris items per person per hour and debris items per kilometer, so it's important to do the survey all in one go, without stopping to do other things.  Of course, short stops to watch a flock of shorebirds, marvel over a rainbow, or just take in the scenery is always encouraged!

Volunteers processing beached birds

Small debris is surveyed in sampling squares according to beach zone.