I have been involved in a Lake Champlain research team focused on understanding the relations between the physical aquatic environment, distributions of fish, and subsequent trophic consequences. Since 2007, I have been studying these dynamics in native rainbow smelt (Osmerus mordax) and nonnative alewife (Alosa pseudoharengus) populations in Lake Champlain, along with comparison studies in several Adirondack lakes and the U.S. Great Lakes.
(map courtesy of Lake Champlain Basin Program)
Rainbow smelt are native to the Lake Champlain basin, whereas alewife moved into the lake (via deliberate human introduction) in the early 2000’s. Both species are planktivores and piscivores, and cannibalism has played a role in historic rainbow smelt population dynamics in Lake Champlain. Cannibalism is a function of both fish abundance and distribution patterns, so we are coupling distribution analyses with simulations of rainbow smelt and alewife predation, cannibalism, and population sizes.
Alewife(Alosa pseudoharengus) :
We are also studying the efficiency and efficacy of sampling pelagic lake fish populations using hydroacoustic, trawl, and gillnet techniques. In some of the systems we are studying, fish are inhabiting the upper few meters of the water column, an area not sampled with down-looking hydroacoustics, so alternative sampling strategies are being developed.