Restoration of Round Whitefish in Adirondack lakes
Conducted by former post-doctoral associate Geoff Steinhart
The round whitefish (Prosopium cylindraceum), once widespread in northern New York, has experienced a reduction in distribution during the twentieth century. Also known as the "frostfish," this fish is characteristic of cold, oligotrophic northern lakes. Formerly known to be resident in more than 80 Adirondack lakes, as of 1979 round whitefish were found in fewer than 15 New York lakes and by 2000 there were only four known remaining self-sustaining populations. Little Moose Lake -- adjacent to the Little Moose Field Station -- contains one of the largest thriving populations of round whitefish remaining in New York State. The round whitefish was first classified as an endangered species by the New York State Department of Environmental Conservation (DEC) in 1983 and was later ranked as a priority species for restoration. Unfortunately, the causes for the decline of round whitefish within their historic range were poorly understood.
From 2004 through 2006, we evaluated the status and recovery of round whitefish in New York, as well as the seasonal distribution, growth and overall ecological role of these fish in lake food webs (i.e. as both predators and prey). Round whitefish consume both zooplankton and benthic invertebrates and, in turn, are prey for native lake trout and non-native smallmouth bass. Based on our research efforts, we have concluded that: (1) many extirpated round whitefish populations resulted from failed human efforts to expand the distribution of these fish during the 1800s, (2) that the decline in round whitefish was caused by a combination of low pH, interactions with non-native species, and failed introductions, (3) non-native smallmouth bass reduced round whitefish recruitment, (4) round whitefish growth is limited by intraspecific competition, and (5) we successfully developed several new methods for capturing round whitefish without extensive mortality in north temperate lakes.
This study was funded by the New York State Department of Environmental Conservation and the U.S. Fish and Wildlife Service.