Complex sentence: During his career, Harkin oversaw the establishment of national parks that include Elk Island, Mount Revelstoke, Point Pelee, Kootenay, Wood Buffalo, Prince Albert, Riding Mountain, Georgian Bay Islands and Cape Breton Highlands.
Split into simpler sentences: During his career, Harkin oversaw the establishment of nine national parks. These include Elk Island, Mount Revelstoke, Point Pelee, Kootenay, Wood Buffalo, Prince Albert, Riding Mountain, Georgian Bay Islands and Cape Breton Highlands.