About Our Great Lakes: Great Lakes Basin Threats

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Images showing erosion, invasive species, oil spill and challenges from lake ice.

Storms, erosion, and high waves

Erosion caused by wind, waves, and human intervention is an unending threat to the Great Lakes region

Water level extremes and climate change

Based on the General Circulation Model, climatologists have determined that the climate of the Great Lakes basin will increase by 2 to 4 degrees Celsius. Warmer air temperatures affect lake levels by reducing runoff and increasing evaporation from the lake surface. Commercial navigation, recreational boating, and hydropower are impacted by extremes in water levels. In 1997-1998 El Nino was responsible for causing drastic changes in lake levels because of the low snow cover. Studies have shown that the predicted increase in temperature will drop lake levels by half a meter to two meters (Government of Canada / U.S. EPA Great Lakes Atlas).

Spills and persistent toxic chemicals

Any toxic chemical spill will have adverse affects on the water quality, wildlife, and overall general health of the lakes.

Habitat destruction

Urban sprawl continues to convert forests, agricultural land, and open space into residential and urban areas, depleting wildlife habitat. Wetlands, which are natural filters of groundwater and home to many different plants and animals, have been lost to agriculture, industrial, and residential uses also.

Threats to water quantity and quality

Some threats to water quality include residential and municipal uses, agricultural runoff, industry runoff and dumping of heavy metals, phosphorus, and other chemicals. Threats to water quantity include proposals that continue to be made encouraging diversion of Great Lakes water to other parts of the world.

Invasive species

What are exotic, invasive, alien, nonindigenous, or nuisance species?

In general, these terms refer to plants, animals, or microscopic organisms growing where they don't belong. In the case of plants, the most common equivalent word is 'weed'. So why are there so many different terms? Each one has a subtly different meaning. "Nonindigenous" or "alien" describe a plant, animal, or microorganism living outside the area where it evolved. "Exotic species" has the same basic meaning, but is used more to refer to a plant, animal or microorganism that is a new or recent invader to an area. In contrast to origin-based terminology, the term "invasive" describes a way of living and reproducing. An invasive species is one that can successfully reproduce and spread to form a sustained population in a new territory. "Nuisance" species are those that cause problems from a human perspective.

For more information see our GLANSIS page.

What is GLERL doing in regard to invasive species?

The Great Lakes Environmental Research Laboratory is NOAA's leading institution for aquatic invasive species research and is mandated by law (P.L. 104-332; 16 U.S.C. 4701 et seq.) to conduct such research. GLERL's research targets two critical areas related to invasive species: (1) prevention and control to stop the inflow and spread of new aquatic organisms, particularly via ship ballast, and (2) minimizing ecological and economic impacts of species invasions by developing the fundamental ecosystem understanding needed for adaptive management strategies. GLERL's current research program includes: assessment of NOBOB vessels, effectiveness of chemical biocides, effects of new invaders on Great Lakes food web, effects of food web changes on Great Lakes living resources, and effects of zebra mussels on nearshore habitat. All of GLERL's current research on invasive species falls within the priorities set by the Aquatic Nuisance Species Task Force and builds directly on the National Management Plan.

For more information see our GLANSIS page.

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