9Formed by glaciers more than twelve thousand years ago, Lake Ontario has captivated nature lovers for generations. Unique among the Great Lakes for having once been connected to the sea, fossils from ocean life have been found near the lake's shores. Damage done to Lake Ontario's ecosystem from centuries of human activity was center stage in the fight to pass the Clean Water Act and the restoration that followed. From incredibly diverse bird migrations in the spring and fall to the squalls and lake effect snow in winter, each season offers a rich ecological tapestry. Author Susan P. Gateley charts the natural history of Lake Ontario from its ice age origins to the climate and habitat challenges it faces today.