Adirondack Brook Trout and Acid Rain: Environmental Legislation Fosters Successful Restoration
Abstract.—Recovery of Brook Trout Salvelinus fontinalis in an Adirondack (New York, USA) lake that was subject to anthropogenic acidification provides a remarkable example of fishery improvement in response to environmental regulation. Studies initiated in the 1950s following a steady decline in Brook Trout populations helped document this recovery. Unsuccessful efforts to maintain a fishery in Honnedaga Lake with hatchery-reared fish in the 1950s forced managers to look beyond stocking, the primary approach employed until that time. As a result, fishery scientists collaborated in the 1960s and 1970s with researchers from other disciplines, providing a broad understanding of atmospheric inputs, watershed processes, and chemical interactions influencing lakes and streams. Extensive studies in the 1980s confirmed the connection between Brook Trout mortality and airborne emissions of strong acid nitrogen and sulfur compounds that released toxic inorganic aluminum from increasingly acidic soils. Political debates in that decade focused on federal regulatory efforts to reduce these emissions, which culminated in passage of the Clean Air Act Amendments of 1990. Within the next decade, Brook Trout that took refuge within a few well-buffered, groundwater-fed tributaries began to recolonize Honnedaga Lake as conditions improved in the main lake due to reduced atmospheric deposition of sulfur dioxide and nitrogen oxides. Since then, management of Honnedaga Lake in the 21st century relied upon natural reproduction by wild Brook Trout. Ultimately, social and political decisions made far away from the Adirondack Mountain region developed regulations that fostered recovery of the Honnedaga Lake fishery by restoring necessary water-chemistry conditions. The recovery of Honnedaga Lake highlights three lessons. First, environment and habitat conditions must be suitable before fishery management actions can be effective. This criterion requires a broad understanding of environmental conditions that sustain fisheries, incorporating insights from atmospheric sciences, geology, and limnology. Second, natural reproduction of Brook Trout in Honnedaga Lake successfully increased population abundance without the additional intervention of stocking hatchery-reared fish. Finally, successful management of Honnedaga Lake required political support and regulatory action from beyond the Adirondack region, as well as media attention.