Figure 1.

Schematic illustration of locations and contemporary drainage connections among the 12 lakes used in this study. In Ontario, Ashby (AS), Mayo (MA), and Salmon Trout (ST) drain into the Ottawa River through the Madawaska River (Ottawa R. drainage). Looncall (LC), Shadow (SH), and Monck (MO) drain into the north side of Lake Ontario through the Trent River (Trent R. drainage). In the Adirondack region of northern New York State, three lakes drain north into the south-shore St. Lawrence River drainage. Lake Rondaxe (RA) drains through the Black river into the southeast side of Lake Ontario; Round Lake (RU) and Rollins Pond (RL) drain into the St. Lawrence River through the Raquette River and Lake Champlain, respectively. Lakes that drain south through the Adirondack region empty through the Hudson River drainage to the Atlantic Ocean and include Harris (HA), Paradox (PA), and Lewey (LE).