D & BACK E COMMISSION THROUGH 125 YEARS B Y J O E K O S A C K ping mountainsides of vegetation, making them more susceptible to erosion. Dams being built on waterways stopped annual fish migrations. Poisonous discharges from factories, flooded mines and cesspools strangled aquatic life in waterways. Residential and agricultural development also swallowed important, sometimes irreplaceable, wildlife habitat, particularly wetlands and lowlands. By the 1890s, Pennsylvania's wildlife community had lost several long standing members. Elk had been extirpated for about 25 years. Wolves, mountain lions and fishers mostly disappeared in JANUARY 2020 3