Volunteers for the “Great Giveback” cleanup on Menhaden Lane Beach met up with staff from the Shelter Island Public Library Saturday morning, Oct. 16, to dispose of bits of plastic and other debris that littered the beach and nearby dunes.

The event was open to adults as well as children, and possibly none pitched in as enthusiastically as two 5-year-olds, Dexter Berger and Owen Portilla.

The important work of cleanup was lightened by the discoveries that turned the project into a treasure hunt. Dexter discovered the exoskeleton of a snake, and Owen came upon the tiny but perfect shell of a baby spider crab, as well as what would appear to unknowing adults to be a plank of wood, but which Owen identified as “a piece of a pirate ship.”

Dexter and Owen — described by library staff as an “honorary librarians” — worked alongside adult volunteers such as Allison Herron and library staff members Nell Cava and Sara Garcia. Ms. Garcia, who directs youth services at the library, said “it was nice to see how many people turned out” to pitch in for the Great Giveback, a countywide service project that takes place every October.