Welcome to the web site for NOAA Research, NOAA's Office of Oceanic and Atmospheric Research

Archive of Spotlight Feature Articles

Multiple Stressors, Multiple Consequences
Muck, harmful algal blooms and changing fisheries plague Saginaw Bay; researchers look into why

GLERL researcher washes a sediment sample which will be taken back to the lab for analysis.

Photo Credit: Juli Dyble Bressie
GLERL researcher washes a sediment sample which will be taken back to the lab for analysis.

It’s reached the point in the season where beach-goers can’t seem avoid the decaying algae riddling the Saginaw Bay shoreline just inside of Lake Huron.

"The smell sensation you get is like you are standing in a barnyard," longtime resident Warner Price, 74, said describing the "dark, black, decaying mess" that has been caking his beachfront property for the last decade.

Price a resident of Port Austin – at the top of Michigan’s thumb – for 63 years, said throughout this time the quality of fisheries and water went in waves. As the lake area first began to deteriorate in the 1970s, he saw government regulations which helped solve problems. Now, the problems with algae, muck, fisheries and poor public perception of water quality have returned.

The Great Lakes Environmental Research Laboratory is in the middle of a research project – Managing Multiple Stressors in Saginaw Bay – which seeks to understand the effects of factors such as invasive species, water levels and phosphorus on water quality and fisheries in the bay. The project uses an Adaptive Integrative Framework (AIF) approach, which facilitates continuous feedback between researchers and managers to identify effective management solutions. For Saginaw Bay, stakeholders identified water quality concerns including muck, pathogens, and nutrient loading and fisheries concerns including yellow perch and walleye recruitment, and feasibility of reestablishing lake herring in Saginaw Bay.
Collecting.

Photo Credit: Juli Dyble Bressie
Scientists in Saginaw Bay take water and sediment samples for quality and species diversity analysis.

"The reason why this method is so important to us is because, as managers, we are being brought in right from the beginning of the study," said Jim Bredin, assistant to the director for the Michigan DEQ. "We’re telling researchers, ‘these are the management issues.’ This seems to be very seldom done, and we’re hoping researchers can, through this process, see what type of questions managers are up against."

The study is now in its second year (a major field research year) and project lead Craig Stow (GLERL scientist) said they are in the process of identifying a lot of unknowns.

"You have to sort out cause and effect relationships in the ecosystem when you have so many variables at once," Stow said.

For example, invasive zebra and quagga mussels, which entered the Great Lakes in late 1980s, may increase phosphorus availability near lake bottoms. As filter-feeders, they also clear the water allowing more light to reach the bottom of the lake. These two actions increase the likelihood that bottom-dwelling algae will grow to nuisance levels. These mussels have also been shown to spit out toxin-producing algae during filtration, returning them to the water, possibility promoting more extensive harmful algal blooms. The mussels may also impact native fish populations (walleye and perch specifically) by competing with invertebrate prey and altering water clarity.
A GLERL researcher examines dead algae on the Saginaw Bay shoreline that has been causing extreme muck problems.

Photo Credit: Juli Dyble Bressie
A GLERL researcher examines dead algae on the Saginaw Bay shoreline that has been causing extreme muck problems.

The mussels and other factors have interwoven connections which may strain the native ecosystem.

"Everything is so interrelated," said Juli Dyble Bressie, a GLERL researcher focusing on water quality issues. "That’s the cool part, but it’s also the hard part."

Tomas Hook, a Purdue researcher co-leading fisheries research with Steven Pothoven (GLERL scientist), said he hopes this project will lead to a better understanding of the system, and thereby improve management of important Saginaw Bay resources.

Stow said he hopes other coastal areas experiencing problems with multiple stressors can use some of the methods employed at Saginaw Bay.

"Saginaw Bay is sort of a microcosm of problems that are occurring in a lot of coastal areas," Stow said. "Learning what we can here will affect decisions made specifically for the bay area, but it should also have more general application in other coastal ecosystems."

7/6/2009


CLIMATE · OCEANS, GREAT LAKES, and COASTS · WEATHER and AIR QUALITY
ABOUT US
 · RESEARCH PROGRAMS · EDUCATION · HOME

Contact Us
Privacy Policy