Once a widespread breeding bird in the lower Susquehanna River basin, the Black-crowned Night Heron (Nycticorax nycticorax) is today listed as an endangered species in Pennsylvania. Along many of the region’s creeks where they formerly nested, pollution and year-round populations of hand-fed waterfowl have eliminated or severely reduced numbers of the night heron’s prey species including amphibians, aquatic invertebrates (particularly crayfish), and a variety of minnows and other fishes.
