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The Friends of the Cloquet Valley State Forest is dedicated to the protection and preservation of the natural and cultural resources of The Cloquet Valley State Forest and promote responsible enjoyment of this unique treasure.

Forum Sept 18
There will be a forum at Clyde Iron Works, Thursday Sept. 18 at 5 pm. We will discuss reducing mercury pollution in the St. Louis River. Its put on by Minnesota Environmental Partnership, with Friends of the Cloquet Valley, MCEA, Save Lake Superior, SOS Blue Waters, Water Legacy, the Izaak Walton League and others. Protect the St. Louis River! Learn about human health risks posed by mercury and what you can do about it.

Mercury in the St. Louis River

Mercury comes in several forms, the most dangerous to people when it comes to the St. Louis River and the rivers and lakes of northern Minnesota is Methylmercury. That form of mercury is created when tiny organisms metabolize Sulfide and mercury. Mercury in the St. Louis is very high, it is at dangerous levels and a solution to the problem has been controversial and has eluded regulatory control. More than a quarter century has passed since the problem became clear and levels are still very unsafe in the river.

Microorganisms transmute mercury to methylmercury
"Microorganisms (bacteria, phytoplankton in the ocean, and fungi) convert inorganic mercury to methylmercury. Methylmercury released from microorganisms can enter the water or soil and remain there for a long time, particularly if the methylmercury becomes attached to small particles in the soil or water. Mercury usually stays on the surface of sediments or soil and does not move through the soil to underground water. If mercury enters the water in any form, it is likely to settle to the bottom where it can remain for a long time.
The resulting molecule bioaccumulates, small organisms that contain it are consumed by larger until we as humans consume the fish. The resulting concentrations in our bodies are much higher than in those tiny organisms and the amount that is transferred to a developing baby is significantly higher than that in the mother's blood stream. "


HOW UPTAKE HAPPENS IN A BABY in utero  Ed Swain of the MPCA explains it this way :

Methylmercury in lake water attaches to algae, which are eaten by small invertebrates.  
In the digestive system of the invertebrate, the methylmercury binds to the amino acid cysteine, 
and that combination is similar in size and shape to the amino acid methionine, and this fake methionine 
is eventually incorporated into the muscle of fish.  Our bodies conserve it as if it were real methionine
 because it looks like a valuable amino acid.

Clarkson and Magos, two major figures in mercury toxicology state: The high mobility of methylmercury in the body is due to the formation of a complex with the amino acid cysteine. The structure of this complex resembles that of a large neutral amino acid, methionine, and thereby gains entry into cells on the large neutral amino acid carrier. Also look at their Figure 5, which shows how the cysteine-methylmercury complex mimics the larger amino acid methionine. The Figure legend reads: FIG. 5. The methylmercury cation, CH3Hg+, attaches to the thiol ligand of the amino acid cysteine, to form a complex that mimics the structure of the large neutral amino acid, methionine.

There are 5 rivers in our state who's elevated levels of Mercury bring special concerns. The St. Louis is one of them.

The 2012 impaired waters inventory (the last one approved by U.S. EPA) has five rivers that could not be included in the Statewide Mercury TMDL because they were assessed to have mercury levels in fish that will not meet the mercury criterion when the mercury reduction goal of the Statewide Mercury TMDL is achieved. The five rivers are the St. Louis, Vermilion, Kettle, Roseau, and the Red River of the North. You can get more details about the Statewide Mercury TMDL at . Bruce (


Communications between Chairwoman Diver and the MPCA regarding the St. Louis River

The toxicology of mercury and its chemical compounds Critical Reviews in Toxicology

Critical Reviews in Toxicology

St. Louis River Mercury Impairments

St. Louis River Forum Poster

Mercury Human Risk

Neurobehavioral effects of developmental toxicity

Economic benefits of mercury exposure control

Prenatal Methylmercury Exposure and Genetic
Predisposition to Cognitive Deficit at Age 8 Years

Methylmercury and Brain Development

What to do about the problem? If Mercury is changed to its dangerous form, methylmercury in a process that requires sulfide, then it seems prudent to limit the amount of sulfide that is introduced into the water. Anything that causes more toxin to form in the system would need to be prevented.



The lands, lakes rivers and streams of Northern Minnesota which lay north of Duluth in the Clouqet Valley Sate Forest and in the Arrowhead are home to many people, plants and animals and serve the world in many ways. Exploring, protecting and learning about the Cloquet Valley State Forest and the Arrowhead is a wonderful pursuit. We hope you enjoy it.


MN Ecolibrary


Wolves - Its important to understand the reality of wolves. Most are not dangerous and its more likely you'll be harmed in an accident in your car or with a bee sting than by a wolf. Few wolf injuries have occured in the entire United States and most often problems with wolves happen when people enter their territory and when wolves are enticed near by pets, food and livestock. Like most of us, wolves go where the food is.

If you see a wolf you most likely have chosen to be in an area with wildlife. Therefore it makes sense to learn about wildlife and respect it.

There are plenty of good references. Wolves are far more at risk from people than people are from wolves. Be a protector, be a smart rural community member, learn to live with wildlife.

There are plenty of things to fear in the world, but in NE Minnesota, wolves are not one of them.

Local residents own wolf dog hybrids in the CVSF and it is important to be certain what you are seeing. Hybrids have many of the behaviors of wolves and are habituated to humans.

Wolf relationships with deer populations are not as simple as one might think.


From the International Wolf Center: Resources for Living with Wolves


Do not feed wolves

Feed all pets indoors, leave no food outdoors

Garbage should be disposed of in cans with tight lids

Do not feed wildlife: wildlife including birds are prey and feeding them will attract wolves.

Don't leave pets on chains or ropes or leads unattended.

Pets left in a kennel should be in a COVERED kennel

Motion Sensor lights can function as a deterrant

Do not feed wolves, do not entice wolves to come close nor approach them. Leave them room to escape. Do not allow a wolf to come close to you. If a wolf seems fearless or comes closer or growls or snarls throw an object at it, yell, raise your arms and wave them in the air. Back away.


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Friends of the Cloquet Valley State Forest

  "That land is a community is the basic concept of ecology, but that land is to be loved and respected is an extension of ethics.”Aldo Leopold

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