OYSTER BAY – Every weekend between April and October, a group of volunteers from Friends of the Bay go out on a small boat to conduct water quality testing in 19 locations along the harbor. Executive Director Patricia Aitken says the data helps detect trends that may be damaging and is an important component of the group’s programs. Additional efforts to increase public awareness and protect the bay have included a beach cleanup that collected two tons of garbage. Most of the volunteers, including Aitken, have fond memories of bird-watching, swimming and being out on the water. They say they want to preserve the waters for other people and marine life to continue to enjoy.