Emerging Nutrient Crisis Causing Massive New Breakdowns in the Great Lakes

NWF to testify today before U.S. Senate Subcommittee on new report as part of federal examination of nation-wide nutrient pollution epidemic

10-04-2011 // Jordan Lubetkin
Lake Huron

The National Wildlife Federation today released a report documenting new and massive ecosystem breakdowns in the Great Lakes caused by interactions between excessive fertilizer run-off from farms and invasive zebra and quagga mussels. The report comes on the same day that NWF is testifying before the U.S. Senate Environment for Public Works Subcommittee on Water and Wildlife on the report findings.

The report, “Feast and Famine in the Great Lakes: How Nutrients and Invasive Species Interact to Overwhelm the Coasts and Starve Offshore Waters (pdf),” details the links between enormous algal blooms in Lake Erie that threaten the health of people and wildlife and a 95 percent decline in fish biomass in Lake Huron.

“Too much food is causing massive algal blooms in Lake Erie and other coastal systems, while too little food is making fish starve in Lake Huron’s offshore waters,” said Andy Buchsbaum, regional executive director of the National Wildlife Federation’s Great Lakes Regional Center. “Nutrient-rich runoff from farms is growing a huge crop of algae along the lakes’ coasts, but those nutrients aren’t making it out to the water in the middle of the lakes. Quagga mussels are consuming almost all of it, leaving nothing left in the water for fish to eat.”

The dual feast-and-famine crises plaguing the Lakes, according to the report, are leading to a collapse of the base of the food web, declines in desirable sport fish populations such as lake whitefish and salmon, and resurgence of toxic algae blooms and the Lake Erie “Dead Zone.”

“This feast-and-famine dichotomy is unprecedented,” said report-co-author Julie Mida Hinderer. “Rapid and drastic ecosystem changes are altering the Great Lakes from top to bottom. The impacts we're witnessing are a sign that the Great Lakes need urgent help.”

Among the report findings that illustrate how excessive nutrients are overwhelming coastal areas:

  • This summer Lake Erie experienced the worst toxic algal bloom in recorded history – worse than when the lake was declared dead in the 1960s.
  • The bloom, involving the toxic alga Microcystis, at one point extended across almost the entire western basin and into the central basin, and in some places was up to 2 feet thick.
  • The toxic algae can sicken or even kill people. A toxin from the algae was measured in this summer’s bloom at 1,000 times the World Health Organization guidelines for drinking water.
  • Algal blooms are significant, although so far less severe, in Saginaw Bay (Michigan), Green Bay (Wisconsin), and along the Lake Michigan coastline, among other areas, and federal agencies rate nearshore areas in all lakes but Lake Superior as “poor” for nutrient phosphorus concentrations.

The report also documents how invasive zebra and quagga mussels have consumed much of the food in the offshore waters of the lakes, causing fish to starve:

  • The biomass of prey fish (which are fed upon by predators such as salmon) in the open waters of Lake Huron has declined by 95 percent in just 15 years.
  • The populations of the tiny freshwater shrimp at the base of the Great Lakes food web, Diporeia, have declined in Lake Michigan by 94 percent in 10 years.

“This report is a wake-up call that we need to take action now,” said Frank Krist, who chairs the Lake Huron Citizens Fishery Advisory Committee to the Michigan Department of Natural Resources. “That sucking sound you hear is the disappearance of the base of the Great Lakes food web, which is impacting some of the most desirable sport fish in the region. Reversing this damage has got to be a top priority to protect our lakes, our fish and our economy.”

Rick Unger, president of the Lake Erie Charter Boat Association, has seen some of the economic damage first hand. He blames nutrient-fed algae blooms for a steep decline in charter boat captains operating on Lake Erie—from 800 in 2010 to 700 this year.

“The cost of doing business is skyrocketing,” according to Unger, who says that charter boats have to journey at least 10 miles farther out into the lakes to avoid harmful algae blooms to fish. “Bookings are down. People don’t want to go onto the water. Once people have been out in the algae they don’t want to go back. Unless things change, more people will be out of business.”

It will take a comprehensive response, according to the report, to solve the emerging nutrient crisis in the Great Lakes. Among the recommendations in “Feast and Famine” are:

  • Forging a stronger Great Lakes Water Quality Agreement to achieve nutrient-reduction goals;
  • Supporting federal Farm Bill programs to reduce polluted agricultural run-off;
  • Using the Clean Water Act to uphold water quality standards;
  • Focusing protection efforts in Lake Erie; and,
  • Targeting Great Lakes restoration programs to reduce nutrient pollution.

“The challenges facing the Great Lakes are no less severe today than they were in the 1960s when Lake Erie was declared ‘dead,’” said Michael Murray, staff scientist at the National Wildlife Federation and co-author of the report. “Strong federal action and increased coordination helped revive the Great Lakes then. Strong action can help them rebound now—so long as policy makers act with urgency to support solutions that protect the lakes and the people and wildlife which depend on them.”

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