Researchers at BGSU discover winter-loving algae on Lake Erie

Ohio Sea Grant researchers at Bowling Green State University have discovered a winter-loving algae that
may be contributing to the summertime "dead zone."
Drs. Michael McKay and George Bullerjahn, both professors of biological sciences, first observed the
algae, Aulacoseira islandica, in brownish pockets floating under Lake Erie’s ice in February 2007 while
they were on a research trip aboard a Canadian Coast Guard icebreaker. The pair determined that the
plankton sometimes made up as much as 80 or 90 percent of the biomass in collected samples.
Their goal now is to determine whether the diatoms get eaten by zooplankton and other organisms or simply
die and sink to the bottom of Lake Erie.
"If it turns out that most of these diatoms end up on the lake floor, they would provide a large
source of organic carbon for bacteria to decompose, which would consume oxygen," McKay said.
"If this decomposition happens mainly when the water warms up and stratifies, forming a warm upper
layer and a cold lower layer in the summer months, and not during the frigid winter months, it has to be
contributing to the dead zone."
The group will use Sea Grant funding to collect data for the next two winters, including taking part in
several more science cruises. In addition, Environment Canada will use its icebreaker to deploy sediment
traps that will sit on the bottom of the lake during the coldest months of the year, which should help
determine if the diatoms are indeed sinking to the bottom of the lake. Preliminary data should be
available in summer 2010.
To read more about this Ohio Sea Grant-funded research, visit
OSU’s Ohio Sea Grant College Program is part of the National Oceanic and Atmospheric Administration?s Sea
Grant, a network of 30 programs dedicated to the protection and sustainable use of marine and Great
Lakes resources.