These natives of Eastern Europe made their way into the Great Lakes like many other invasives — through the ballast water of ocean-going ships. Scientists say similarities between quagga mussels and zebra mussels masked their presence in Lake Superior. Jack Kelly, a researcher at Duluth's EPA lab, says pinning down their identification didn't come easy.

Researchers have witnessed many changes in the Great Lakes in the wake of abnormally warm winters and summers in recent years. Many lake scientists are examining the impact of warmer temperatures on Lake Superior. Jay Austin is a researcher with UMD's Large Lakes Observatory. He says ice plays a number of roles in the lake.

A seiche is a little-known phenomenon that occurs within the Great Lakes. They are

standing waves that occur in an enclosed body of water. Minnesota Sea Grant Director Stephen Bortone says researchers have spotted seiches in Lake Superior.

The invasion of sea lamprey into the Great Lakes had a significant impact on Lake Superior's native lake trout. Lamprey nearly eliminated lake trout populations in Lake Superior by the 1970s, which led various state agencies to make comprehensive programs to restore the fish. Efforts remain underway to keep the invaders from threatening lake trout.

A charrette is simply a focused effort to resolve community development challenges in a short period of time. Often, a charrette can avoid drawn-out battles between communities and cities over development. Such is the case with the Amity Creek Charrette.

Chemicals like DDT have drawn much attention and concern over the years. The presence of chemicals, such as those from pesticides, beg the question, "What effects are these pollutants having on our environment?" Now scientists are concerned about another round of chemicals making their way into Lake Superior.

Invasive species have been getting a lot of attention with the spread of spiny waterfleas and round gobies to name a few. People outside the scientific community are now realizing the impacts that these foreign invaders have on the Lake Superior. Many groups are combining efforts to prevent the spread of invasive species, especially through the ballast water of ocean-going ships.

Your doctor may tell you that fish is a good source of protein or that their omega 3 fatty acids benefit heart health. But what you may not know are the risks associated with eating fish.

You may have heard about the mystery of corroding steel in the Duluth-Superior Harbor. The problem could cause millions of dollars in damage to the harbor's steel docks and sheet pilings. Now, scientists have discovered that the situation is not unique to Duluth-Superior. According to Duluth Seaway Port Authority Facilities Manager Jim Sharrow, it's in other Northland harbors as well.

Lake Superior has experienced a number of changes over the years. Shoreline development, chemical pollutants and invasive species are some of the challenges facing the largest of the Great Lakes. Scientists gathered at a conference in Duluth to examine and develop ways to face the threats or changes looming for Lake Superior.