facebook
twitter
rss
account
search
search
 

Green algae again fouling Great Lakes

March 1, 2012 at 5:59 PM   |   Comments

HOUGHTON, Mich., March 1 (UPI) -- Slimy green algae that fouled beaches around the U.S. Great Lakes in the 1950s are back with a vengeance due to an invasive species of mussel, scientists say.

The green, bottom-dwelling alga called Cladophora glomerata first choked lake waters in the mid-20th century when humans discharged large amounts of phosphorus from agricultural runoff into the lakes.

Then the Great Lakes Water Quality Agreement brought tough new regulations that limited phosphorus and Cladophora all but disappeared.

Now it's back, researchers at Michigan Technological University report, thanks this time to billions of exotic zebra mussels that have created a perfect habitat.

The mussels, as filter feeders, have clarified the Great Lakes water, allowing more sunlight for Cladophora to grow in areas that were once too dark, the researchers said.

The mussels also excrete a type of phosphorus that Cladophora love to feed on, and the mussels' hard shells covering the sandy lake bottoms provide solid real estate where the algae can grow.

Michigan Tech's Robert Shuchman and his research team are helping resource managers survey the extent of the Cladophora problem.

Using remote-sensing data from satellites the can measure "radiance," or reflective brightness, to distinguish Cladophora beds from areas where the lake bottom is clear.

"By doing this, we can map Cladophora in a straightforward way," he Shuchman said.

© 2012 United Press International, Inc. All Rights Reserved. Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.
Most Popular
1
NASA satellite shows scope of Aral Sea disaster NASA satellite shows scope of Aral Sea disaster
2
600-year-old canoe discovered in New Zealand 600-year-old canoe discovered in New Zealand
3
Apple releases fix for 'Shellshock' virus Apple releases fix for 'Shellshock' virus
4
Social network Ello getting thousands of requests per hour Social network Ello getting thousands of requests per hour
5
Antarctic ice loss responsible for measurable shift in gravity Antarctic ice loss responsible for measurable shift in gravity
Trending News
x
Feedback