In late August news of a “dead zone” in Green Bay seemed to come as a shock to many, even though the bay has long been plagued by the oxygen-deprived conditions known as hypoxia.
For instance, in 2010 the University of Wisconsin – Milwaukee received a $1.3 million grant from the National Oceanic and Atmospheric Administration to study hypoxia in Green Bay and what effect climate change might have on the dead zone.
While Green Bay represents only seven percent of the surface area and 1.4 percent of the volume of Lake Michigan, it receives approximately one-third of total phosphorus loading in all of Lake Michigan, largely due to the Fox-Wolf river watershed that dumps an annual 330,00 tons of sediment and 1,400 tons of phosphorus annually.
The Green Bay dead zone is one of the many issues that were addressed at the eighth biennial State of Lake Michigan Conference, which was held this week in Sheboygan in conjunction with the 13th annual Great Lakes Beaches Conference. It’s the first time the conference has been held in Wisconsin since 2009.
“There’s a tremendous die-off of algae in the summertime that is creating a dead zone in the bay, and that dead zone impacts the fishery, so there’s a whole session on hypoxia, or the dead zone,” said Victoria Harris, water quality and habitat restoration specialist with the University of Wisconsin Sea Grant Institute at the University of Wisconsin – Green Bay and one of the coordinators of the State of Lake Michigan Conference.
Harris said there were a total of 18 sessions on different topics affecting Lake Michigan at the Oct. 15-17 conference.
“About a third of it is devoted to beach management issues because it’s also a joint conference with the Great Lakes Beaches Association,” Harris said.
Other sessions included the Lake Michigan food web and its collapse, fisheries and coastal habitats, two sessions on nutrient problems in the near shore zone, one looking at how to reduce phosphorus input into the lake from watersheds and the other looking at cladophora algae and what can be done about it.
“There’s also a special session on invasive species and what’s being done about that,” Harris said.
The only thing missing at the 2013 State of Lake Michigan Conference was input from federal agencies.
“We lost about 35 people who are federal employees due to the shutdown,” Harris said.
To see the agenda and papers presented, visit aqua.wisc.edu/solm/Home.aspx.