At the Vineyard Conservation Society annual beach cleanup on Saturday, likely debris collections will include an assortment of bottles, cans, cigarettes, and styrofoam.

In 1997 though, Brendan O’Neill and Linsey Lee found an actual message in a bottle. It was a slip of paper in a test tube with a return address for a high school marine biology student. Penny Uhlendorf wrote back on behalf of Vineyard Conservation Society, and she later received a message back from Jon Skillman, who had released the test tubes in 1973 as part of an experiment tracking currents in the Vineyard Sound.

Mr. Skillman told her he had received about 350 responses, though he hadn’t gotten any for more than 20 years. One person told him they found a test tube on the banks of the Detroit River in Michigan. Mr. Skillman said in the flurry of responses two decades prior, he had also heard from a Karl Uhlendorf. Mr. Uhlendorf happens to be Penny’s son.

“It was wonderful,” Ms. Uhlendorf, who organized the cleanup for years, said of the coincidence.

This year marks the 27th annual cleanup, and it will include more than two dozen beaches. While there is no guarantee that the forces of the universe — and the ocean — will connect you to a stranger who decades ago also connected to your son, it is certain that the cleanup will leave beaches a little bit cleaner, and therefore a little bit less hazardous for wildlife. There will also be a zero waste lunch to follow at Sailing Camp Park in Oak Bluffs.

Volunteers will be out on Island beaches from 10 a.m. to noon on Saturday. All are welcome.

For more information about beach locations and to read more about the message in a bottle story, visit vineyardconservation.org.