Great Lakes Environmental Directory Great Lakes Great Lakes environment Great Lakes grants exotic species water pollution water export drilling environment Great Lakes pollution Superior Michigan Huron Erie Ontario ecology Great Lakes issues wetlands Great Lakes wetlands Great Lakes Great Lakes environment Great Lakes watershed water quality exotic species Great Lakes grants water pollution water export oil gas drilling environment environmental Great Lakes pollution Lake Superior Lake Michigan Lake Huron Lake Erie Lake Ontario Great Lakes ecology Great Lakes issues Great Lakes wetlands Great Lakes Resources Great Lakes activist Great Lakes environmental organizations Great Lakes Aquatic Habitat air pollution alien species threatened rare endangered species ecological Great Lakes information Success Stories Great Lakes Directory Home/News Great Lakes Calendar Great Lakes jobs/volunteering Search Great Lakes Organizations Take Action! Contact Us Resources/Links Great Lakes Issues Great Lakes News Article About Us Networking Services

Great Lakes Article:

Swarms of mayflies not harmful -- just creepy
By Rob Amen
Valley News Dispatch

They may bug you, but an expert who studies mayflies, which once again have descended upon the Valley, said they will cause you no harm.

Mayflies are large, transparent-winged insects that rise from river bottoms, float on the surface and mate in the air before dying, usually within 72 hours. Their appearance in the Pittsburgh area -- you'll remember they hovered, then covered, PNC Park during a Pirates game a couple years back -- signals clean, viable waterways.

And contrary to popular opinion, they are not mosquitoes; they don't bite; and you cannot contract West Nile Virus from them.

"They really don't do anything in terms of harming anyone. They may be more of a nuisance to some people," said Edwin C. Masteller, emeritus professor of biology at Penn State, Behrend, who studies aquatic insects. "What it means is there's a lot of food for fish. As they're coming up the water, I'm sure a lot of fish are feeding on them."

Masteller said mayflies typically spend two to three years as nymphs in water such as Pittsburgh's three rivers or Lake Erie before ascending to the surface. After they fly away, they mate; females lay their eggs -- as many as 8,000 -- on the water's surface, then die, along with the males.

Reports have suggested mayflies were scarcely seen in the Pittsburgh area during the past 150 years, and Masteller said they were absent from the Erie area dating to the 1950s before beginning to emerge in 1997. By 1999, mayflies had become a common sight around the lake. Masteller said local meteorologists even included Doppler radar showing echoes of large swarms of mayflies during television newscasts.

Mayflies in Pittsburgh, which Masteller said likely are a different genus and species than those in Erie, began noticeably surfacing in 2001. As long as they deem the waterways clean, they'll probably stick around, Masteller said.

But he reiterated that they are harmless.

"They won't bother you at all," Masteller said. "Their only intent is to find a mate."

This information is posted for nonprofit educational purposes, in accordance with U.S. Code Title 17, Chapter 1,Sec. 107 copyright laws.
For more information go to: If you wish to use copyrighted material from this site for
purposes of your own that go beyond "fair use," you must obtain permission from the copyright owner.

Great Lakes environmental information

Return to Great Lakes Directory Home/ Site Map