Populations of primary forage fish (alewife) have declined and their ability to sustain current salmonid fishery is questioned. Lower trophic level indicators are being developed together with NYDEC to see if it is possible to have a warning signal for management of large systems like Lake Ontario. Mysids can now be estimated with hydroacoustics that are collected for fisheries assessment. This method is also being used in other Great Lakes by the U.S. Geological Survey and the Ontario Ministry of Natural Resources, and for large lakes in Europe.
impact statement issue
Large lakes like Ontario, Erie and Champlain are undergoing ecological changes with unpredictable consequences to their ecologies. We need to understand the components of the food webs and how they are rearranged in the face of new invaders and changing ecosystems.
impact statement response
We have several research projects on Great Lakes food webs, including an analysis of the alewife invasion in Lake Champlain, zooplankton as indicators of ecosystem change in Lake Ontario, and dynamics of mysid shrimps. This includes a new invader: the nearshore mysid Hemimysis anomala. In addition, we develop acoustic techniques for measuring the distribution and abundance of these components.
impact statement summary
Ecological change in large lakes affect the livelihood of large number of people. Food web dynamics is at the heart of these changes as they affect fish and fisheries. We have developed methods to assess lower trophic levels on which fish depend and are analyzing the effects of ecological change on the whole food web.
Other private funding
New York Sea Grant/ Champlain Sea Grant/Great Lakes Fisheries Commission
