WASHINGTON (AP) — Art Cooley, a longtime activist who co-founded the Environmental Defense Fund more than 50 years ago, has died. Cooley, 87, helped launch the group, now one of the world's leading environmental organizations, from his living room on Long Island, New York, in 1967.

EDF now has more than 2.5 million members and nearly 1,000 employees from New York to London to Beijing.

Cooley died Sunday in Colorado of natural causes, said his son, Jonathan.

In the mid-1960s, while a high school teacher, Cooley was one of several local activists who organized to stop use of the pesticide DDT, a toxin that was threatening survival of birds including the osprey, bald eagle and peregrine falcon. The legal battle led to the banning of DDT in the United States and the formation of EDF.

Cooley was involved with the organization's board, including as its chair and later secretary, for decades. He grew up on Long Island and was later a long-time resident of La Jolla, California.

"Art had a warmth and charisma that radiated through EDF board meetings and helped bring people together in common cause,'' said EDF's longtime president, Fred Krupp. "For all of us who carry the EDF torch ... knowing Art will go down as one of the great satisfactions of our lives."

Cooley and his associates used science to challenge industry groups in court and helped establish the right of ordinary citizens to sue the government to protect human health and the environment, EDF said in a statement.

Cooley's death leaves Charles Wurster as the group's last surviving co-founder. Another co-founder, Dennis Puleston, died in 2001.