Complex sentence: However, he continued to work as an advocate for wilderness preservation; soon after his retirement, he was elected president of the Virginia Wilderness Committee, and he served as mentor to a new breed of conservationists and lobbyists for wild land protection.
Split into simpler sentences: However, he continued to work as an advocate for wilderness preservation. Soon after his retirement, he was elected president of the Virginia Wilderness Committee, and he served as mentor to a new generation of conservationists and lobbyists for wild land protection.