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Two Generations, and $70 million later, Muskegon Lake is Restored

By Audrey WhitakerCircle of Blue

The Great Lakes News Collaborative includes Bridge Michigan; Circle of Blue; Great Lakes Now at Detroit Public Television; and Michigan Radio, Michigan’s NPR News Leader; who work together to bring audiences news and information about the impact of climate change, pollution, and aging infrastructure on the Great Lakes and drinking water. This independent journalism is supported by the Charles Stewart Mott Foundation. Find all the work HERE.

“With the conclusion of cleanup efforts on Muskegon Lake, the area has seen an increase in property values and tourism, illustrating the intrinsic connection between the community and its shoreline.”

  • In West Michigan, Muskegon Lake will be removed from the list of Great Lakes Areas of Concern.
  • The completion of restoration efforts comes after over 30 years and $70 million invested in cleanup.
  • Along with the progress and promise of economic revitalization, there is still work to be done to protect water resources in this Lake Michigan Shoreline community.

Before the United States and Canada formally declared Muskegon Lake an “area of concern” the 4,149-acre expanse of polluted, sediment-choked, debris-congested water at the mouth of the Muskegon River was so repulsive that only rats and hungry gulls plied its shores.

More than a century of abuse by sawmills, chemical plants, energy installations, and raw sewage produced conditions so vile that by the early 1980s the lake was all but ecologically dead. In 1987, under the provisions of the Great Lakes Water Quality Agreement, a joint U.S.-Canada pact to clear pollution from the waters of the Great Lakes, Muskegon Lake and its tributaries were designated as one of 43 similarly polluted areas of concern; 26 are located in the U.S., 12 are located in Canada, and five are shared by both countries.

The history of toxic cleanups in the U.S. includes ample evidence that the work is expensive and success is achieved over decades. That is certainly the case with Muskegon Lake. Last May, local, state and federal officials gathered at Heritage Landing, a former industrial-scrapyard-turned-waterfront park on Muskegon Lake’s south shore to declare that the $70 million project to cleanup, remediate and restore Muskegon Lake was complete.

“There is no law, there’s no private cause of action, there’s no ability to sue within the water quality agreement,” said Jon Allan, senior advisor at the University of Michigan School for Environment and Sustainability, and U.S. co-chair of the Great Lakes Water Quality Board. “All it says is the two governments see a common problem, and they say ‘we’ll work on this together.’”

“When [AOCs] were designated, they were designated as the most contaminated places. Shouldn’t the most contaminated places get additional attention because the people who live there have suffered from that for a very long time,” Allan added. “We know enough to act, so let’s use those dollars to act.”

In Muskegon, life after delisting holds the promise of economic revitalization. With the conclusion of cleanup efforts on Muskegon Lake, the area has seen an increase in property values and tourism, illustrating the intrinsic connection between the community and its shoreline.

This has spurred enthusiasm in the community, which has struggled to overcome economic depression throughout its history and to establish itself as a tourist destination on the Lake Michigan shoreline.

While this enthusiasm and sense of accomplishment is important, after delisting, community leaders must grapple with the perception that their work is done.

The indicators of water health identified in the 1980s do not address issues such as climate change or invasive species, all of which amplified after the GLWQA was signed 50 years ago.

While the EPA recognizes these issues and their effect on the Great Lakes region, they are not part of the AOC program, said Al Steinman, director of the Annis Water Resources Institute in Muskegon, Michigan.

“Every AOC, I don’t care where you are, that’s already been delisted or will be delisted in the future still has ecological problems that need to be addressed,” Steinman said. “The key, then, is how do you communicate that to a community after it’s been delisted and you’ve had this huge celebration to get off the list?”

In Muskegon, PFAS contamination remains a major detriment to the health of the lake, along with the presence of harmful algal blooms.

Eric Kuhn, executive director of the West Michigan Shoreline Regional Development Commission, said that maintaining a relationship with local stakeholders and creating a long-term management plan is key to maintaining the restoration work and to future stewardship.

Muskegon has been fortunate, given the close proximity of the Commission, Grand Valley State University’s Annis Water Resources Institute, Muskegon Lake Watershed Partnership and NOAA’s Lake Michigan field station. There are natural opportunities for partnerships in the area, Kuhn said.

“Having those strong partnerships really made us be able to accomplish [restoration efforts] faster,” Kuhn said.

“It’s their community’s future, and it’s ultimately their responsibility when the state and federal funding is shifted to other areas,” said Collin Knauss, who serves as the project development manager for the Great Lakes Protection Fund.

The ‘Great Northern Diver’ – Common Loon Sightings Becoming Increasingly Rare in the Great Lakes Region

by Scott Brown
MWA e-Newsletter Editor

Prompting the return of a flood of fond memories of northern pike and walleye fishing with my son and grandson while on fly-in fishing trips to northern Ontario’s Shabuskwia Lake, the other worldly sound of a loon’s call has always held special meaning for this ageing baby boomer.  Although I have not visited this gorgeous wilderness lake in many years, my son and wildlife biologist grandson tell me that loon sightings even in the far north have become increasingly rare.

Although there are five species of loon in North America – all member of the Family Gaviidae, including Red-throated Loon, Pacific Loon, Yellow-billed Loon, and Arctic Loon, the most abundant is the Common Loon (scientific name: Gavia immer). The International Union for the Conservation of Nature reports that the majority of the approximately 640,000 common loons that remain on earth are found in Canada.

Though they are awkward on land due to the fact their legs are placed far back on their bodies, common loons have evolved as water birds that venture onto shore only to mate and incubate eggs, and learn how to dive long before they learn how to fly. Though the name loon derives from their goofy, awkward walk, they are often referred to as ‘great northern divers’. Capable of staying submerged for up to five minutes as they forage for fish and aquatic insects, loons are particularly well adept at hunting underwater due to their solid bones that make them less buoyant, their capacity to rapidly expel air from their lungs, and their ability to flatten their feathers in order to expel air from their plumage. The capacity to stay submerged for long periods is also enabled by their extraordinary physiological capacity to slow their heart rate while diving in order to conserve oxygen. The red eyes of loons have also evolved to allow them to detect fish and other prey in the low light conditions that are often present in water depths of up to fifteen feet. Empowered by their capacity to rapidly descend and to swim at an extraordinary fast pace while underwater, loons are considered highly effective hunters that are capable of consuming a large quantity of small fish in relatively short order. Biologists familiar with the unique bird species have estimated that a single set of loon parents and their two chicks are capable of eating a half ton of fish in a single fifteen-week season. Due to their reliance upon diving to depths of up to fifteen feet to forage for food, loons prefer healthy inland lakes hosting relatively clear water and healthy fisheries. Loons are known to shy away from inland lakes suffering from poor water clarity. Frequent loon sightings in a particular region are considered a reliable indicator of the presence of large, healthy inland lakes hosting abundant fish populations, relatively clear waters, and the existence of undisturbed natural shorelines.

Graced with relatively small wings in comparison to their size and weight, loons are attracted to large lakes that provide them with an opportunity to takeoff into the wind and skitter across the water’s surface for a long distance before creating enough aerodynamic lift to eventually become airborne. Once airborne, however, common loons are capable of flying at speeds of up to 70 miles per hour. It is interesting to note that their need for long, water-based take off ‘runways’ has caused migrating common loons to become stranded as they sometimes mistake wet highways and parking lots as rivers and lakes.

Due to their relatively large bodies, small wings, and the fact that their fast flight requires a lot of energy that must be replenished along the way, common loons are considered a medium-distance migrants. The common loons of the northern United States and Canada migrate from lakes to the coastal oceanic waters of the Pacific or Atlantic. The loons of western Canada and Alaska migrate to the Pacific Coast ranging from Alaska’s Aleutian Islands to Mexico’s Baja Peninsula. Great Lakes region common loons migrate to the Gulf of Mexico or Florida coasts. Common loons that inhabit the lakes of eastern Canada migrate to the North Atlantic Coast.

Sharp declines in the abundance of all five loon species in North America have thus far been primarily attributed to the loss of critical habitat caused by steadily increasing rates of near shore residential development that has been occurring on thousands of larger northern temperate inland lakes located in the United States and Canada. Intensive lakefront development facilitated loss of optimal loon habitat and a commensurate loss of preferred nesting and rearing habitat is one of the primary reasons that loon populations have experienced a steady decline over the course of the past fifty years.  Ecologists familiar with the decline of loon populations in North America also indicate that multiple stressors including the not yet well understood influences of climate change, diminished fish populations, acidification of inland lakes, and the loss of eggs and chicks to an increasing number of scavenging predators have also contributed to the decline of loons. It is important to point out that common loon populations in the Laurentian Great Lakes region have also experienced decline due to the onset of increasingly frequent outbreaks of  Type-E botulism that has caused massive annual die-offs of common loons, and other fish-eating birds in the past twenty five years.

Hundreds of Thousands of Failing Septic Systems Contribute to an Ongoing Major Public Health Issue in Michigan

Groundwater, and the Waters of our Fragile Lakes, Rivers, and Streams

are Subject to Contamination by Failing Residential Septic Systems

by Scott Brown

MWA E- Newsletter Editor

Attributed to the fact that Michigan continues to be the only state within the United States of America that has not yet enacted a state-wide law requiring regular septic system inspections, and to the fact that only eleven out of eighty three, or 13% of counties in Michigan have enacted local regulations that require regular septic system inspections, hundreds of thousands of failing septic systems continue to be a major source of e-coli and human fecal bacteria laden raw sewage that contaminates ground water, and renders the waters of many our lakes, rivers, and streams unfit for total contact water sports such as swimming or snorkeling. The steadily escalating environmental and public health associated problem is derived from that fact that approximately 20%, or 280,000, of the 1.4 million septic tanks that were constructed in the 1950’s and 1960’s throughout Michigan are now failing. The problem has also been exacerbated by the fact that many Michigan homes, and their now severely antiquated septic systems were built prior to the construction of sewer systems that now serve even the smallest of towns and villages.

Septic systems, otherwise known as on-site waste water disposal systems, are designed and installed in order to manage and treat the waste generated by toilets before it reaches ground water. In a properly designed septic system, the septic tank serves to remove larger solids from wastewater. Wastewater that flows out of the septic tank is saturated with contaminants that must be removed before the water can safely be combined with surface and/or groundwater. Public health issues stem from the fact that septic tank effluent contains large concentrations of toxic micro-organisms that are capable of making people sick. Moreover, the organic matter present in wastewater effluent creates bad odors, and contains algae growth stimulating nutrients (nitrogen and phosphorus) that can have a negative impact on aquatic ecosystems. Properly designed septic systems include a disposal field comprised of a mixture of sand, silt, and clay that are often referred to as loamy soils that act to successfully treat bacterial and inorganic compounds. Phosphorus that is produced within the household that passes through the septic tank is also captured within a properly designed disposal field’s soil.

On-site waste water disposal systems continue to be installed in support of residential and commercial development that occurs in rural settings where sanitary sewer systems are not available. According to Michigan State University Extension, when an on-site waste water disposal system is correctly located, properly designed, carefully installed, and properly maintained, they are capable of serving as effective waste disposal systems that are economical and that do not pose a threat to public health or to the fragile ecosystems of surrounding streams, rivers, and lakes.


Michigan’s on-going failing septic system crisis is best exemplified by Kent County where a volunteer only septic system inspection program allows an estimated 11, 250 failing residential septic systems distributed throughout the county to leak approximately one million gallons of raw sewage into vulnerable groundwater supplies each day. In inland lake inundated Oakland County, as another prime example, where public health threatening cases of e-coli contamination of rivers and lakes are reported on a more and more frequent basis, and where county officials have also yet to establish a program that would mandate regular septic system inspections, approximately twenty-five to thirty percent of the 100,000 septic systems located in Michigan’s most affluent county are known to be leaking. The gravity of the situation is also effectively illustrated by the fact that the results of a 2015 study conducted by Michigan State University researchers on sixty-four Michigan rivers revealed that concentrations of e-coli that were higher than U. S. Environmental Protection Agency permitted water quality standards. The significance of the issue is also amplified by the fact that the Michigan Department of Environment, Great Lake, and Energy (EGLE) reports that approximately one half of Michigan’s thousands of miles of rivers and streams suffer from concentrations of toxic e-coli that exceed minimum water quality standards. 


Representing a major environmental and public health issue that promises to escalate in significance as increasing numbers of septic systems fail and begin to leak with the passage of time, past efforts to enact legislation that would have established a meaningful statewide standard for how septic tanks are designed, built, inspected, and maintained have sadly disintegrated in the face of arguments suggesting that in addition to treading on individual property rights, regulating septic tanks in a manner that would require regular inspections and maintenance would be too costly for homeowners, over burden local health departments, and make it more difficult to sell homes.


It is important to note, however, that Michigan Governor Whitmer recognized the significance of the on-going problem and declared the week of September 20-24, 2021 as Septic Smart Week that encouraged homeowners and communities to properly maintain their increasingly vulnerable septic systems. In addition, Governor Whitmer and Senator Jon Bumstead proposed dedicating $35 million of the 2022 state budget to enable the establishment and funding of an EGLE administered program that would make low interest loans available to homeowners seeking to repair, replace, or eliminate leaking residential septic systems.

The latest attempt at passing legislation that would require septic tank inspections was introduced as House Bill 6101 on May 17, 2022 by Representatives Yaroch and Rendon, and was referred to the House Committee on Natural Resources and Outdoor Recreation. Known as the “septic tank inspection at time of sale act”, due to an upcoming election, and perceived wide spread opposition to the legislation, neither the Michigan House of Representative or the Michigan Senate took any sort of action on the bill. Only time will tell if Governor Whitmer and the leadership of both houses of the Michigan legislature will pursue a viable solution to an on-going environmental crisis by enacting a state law requiring property owners to inspect and maintain their septic systems on a regular basis. 

For more information on how failing septic systems are capable of degrading our precious freshwater resources, visit the U. S. EPA’s web page entitled “How Your Septic System Can Impact Nearby Water Sources” . The always wise, inland lakes preservation focused folks from northwest Lower Michigan’s Glen Lake Association have also created a septic smart webpage that contains valuable information regarding the proper maintenance of septic systems. 

Great Lakes Region State Governments Confronted with a Significant Challenge in Working to Mitigate an Increasingly Widespread PFAS Contamination Problem

by Scott Brown, MWA E-Newsletter Editor and Board Director

Electronic and print media news articles focused on the harmful environmental impacts and enhanced risks to human health associated with a large group of odorless, invisible toxic chemicals referred to as PFAS seem to appear almost every day. Present in soil, sediment, groundwater, wastewater, food, drinking water, and within the waters of our lakes and streams, per-and polyfluoroalkyl substances (PFAS) are a large group of man-made chemicals that include both perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) that were initially developed by Dupont in the 1940’s. Widely utilized by manufacturers, a few commonly occurring examples of products containing large concentrations of PFAS include firefighting foam, and a wide array of popular consumer products. These include, to cite just a few examples, heat-resistant non-stick cooking surfaces such as Teflon cooking pans, water proofing and fabric protection products, cosmetics, shaving cream, nail polish, food wrappers, takeout containers, carpet, leather, and pet food bags. It is also important to point out that PFAS are sometimes referred to as “forever chemicals” due to the fact that they tend to accumulate over time in the human body and do not break down easily due to their long half-life.

Even in relatively low concentrations, exposure to the vast suite of chemicals known as PFAS has been directly linked to significant increases in the risk of acquiring certain forms of cancer, or of suffering from reproductive and developmental problems, thyroid disease, high cholesterol, or ulcerative colitis. According to the Centers for Disease Control and Prevention (CDC), approximately 95% percent of the citizens of the United States currently have PFAS in their bodies. Moreover, due to the fact that PFAS is now so prevalent in groundwater, soil, and livestock feed, it is also regularly detected in blood samples extracted from milk cows, cattle, sheep, hogs, and other widely consumed sources of meat such as chicken and turkey. Of particular concern to the State of Michigan, and other states including Ohio, Pennsylvania, and New York that each have coastlines on Lake Erie and Lake Ontario, however, are the relatively large concentrations of PFAS that are being detected in samples of freshwater fish.

The just released results of a new study conducted by the Environmental Working Group (EWG), a non-profit organization dedicated to creating a healthier environment, strongly suggests that PFAS contamination of freshwater fish maybe of special concern to people who depend upon fishing out of economic necessity in the Detroit River, or within other heavily urbanized areas that exist on coast of Lake Erie and Lake Ontario where fish tissue samples detected higher than average levels of PFAS contamination. The study indicated that “widespread PFAS contamination of freshwater fish in surface waters in the U.S. is likely a significant source of exposure to PFOS and potentially other perfluorinated compounds for all persons who consume freshwater fish, but especially for high frequency freshwater fish consumers.”  National testing of fish tissue completed by the United States Environment Protection Agency shows that while nearly all fish present in the rivers and streams of United States possess detectable levels of PFAS, the Great Lakes, and in particular certain areas of Lake Erie and Lake Ontario, are now known to host fish with the highest concentrations of PFAS in the nation. The Environmental Working Group study also suggests that due to the fact that self-caught fish are an important source of subsistence for many individuals living in heavily urbanized areas, fish consumption targeted PFAS advisories are likely to disproportionately affect people who are not likely to be able to afford to replace self-caught fish with commercial fishery sourced fish purchased from their local grocery store. The authors of the EWG study also provides a cautionary note which suggested that consuming a single serving of yellow perch caught in certain areas of Lake Erie, for example, equates to drinking a thirty-day supply of PFAS tainted water. The EWG sanctioned study, entitled “Locally caught freshwater fish across the United States are likely a significant source of exposure to PFOS and other perfluorinated compounds” appeared in the January 2023 edition of the scientific publication entitled Environmental Research.

Providing a seemingly unlimited supply of high-quality freshwater and a viable means of navigating to the outside world via the St. Lawrence Seaway, the Laurentian Great Lakes region has served over the course of last century as the North American base for the automotive, steel, petroleum, and chemical industries, and is therefore particularly vulnerable to the human health and environmental impacts that have thus far been associated with PFAS. Even though PFAS is present in nearly every state, a review of the map which appear below indicates that Great Lakes region states, and particularly Michigan, possess an inordinate number of sites hosting high concentrations of PFAS.  As the map clearly suggests, states bordering the Great Lakes each face a significant economic, environmental, social, and logistical challenge in seeking to contain and prevent further contamination of immensely valuable freshwater ecosystems by the harmful chemicals.

In response to widespread PFAS contamination, the Michigan Department of Health and Human Services encourages people to follow the Eat Safe Fish Guides.  The annually updated guidelines provide readers with a detailed breakdown based on fish species, where it was caught, and which pollutant is the problem. The State of Michigan has also created a PFAS Action Response Team (MPART) which is approaching the increasingly widespread PFAS problem with a “unique, multi-agency proactive approach” for coordinating state resources that are being dedicated to addressing the complex problem. The State of Michigan also suggests that those who are especially concerned about their exposure to PFAS can visit the state’s Michigan PFAS Action Response Team (MPART) page for valuable resources and information on areas of the state where water is being tested and where sources of acute contamination are monitored and investigated. Information from MPART on health concerns can be found on their webpage

Clean Lakes Support – Now’s the Time!

by Ralph Bednarz, MWA Director and NALMS Region 5 Director

The Michigan Waterfront Alliance (MWA) Board is excited to share with you some information about an advocacy campaign for restoring funding to, and enhancing Section 314 of the Clean Water Act (CWA), formerly known as the Clean Lakes Program.

When the Clean Water Act (CWA) was enacted in 1972, Congress explicitly acknowledged the importance of healthy lakes in Section 314. This voluntary Clean Lakes Program provided funds to help assess the water quality of lakes in a state or tribal jurisdiction, conduct diagnostic feasibility studies to identify the causes of pollution in the lake, implement projects to mitigate the problems, and carry out post-restoration monitoring studies. The Clean Lakes Program awarded $145 million in grants through 1995. But Congress has appropriated no funds for the Clean Lakes Program since 1995, even though 45% of the nation’s lakes continue to be in poor condition as a result of nutrient enrichment and other stressors, according to the most recent National Lakes Assessment .

Michigan was awarded a lake classification grant in 1980 which supported the state’s inland lakes water quality monitoring and assessment program. In addition to the lake classification grant support, Michigan was awarded 16 individual project grants: seven Diagnostic-Feasibility Studies (Phase I) awards, eight Restoration and Protection Implementation Projects (Phase II) awards, and one Post-Restoration Monitoring Studies (Phase III) award, during the time period of the Section 314 Clean Lakes Program financial assistance.

Another important part of the CWA is Section 319 Nonpoint Source Program that was established in the 1987 Amendments to the Act. Since 1990, the Environmental Protection Agency (EPA) has been providing financial support to states and tribes through Section 319 grants to implement their nonpoint source management programs.

The EPA has encouraged states and tribes to use Section 319 funds to support the Clean Lakes Program work previously funded under Section 314. The use of Section 319 funds to support lakes-related projects varies widely by state and tribes but it has been reported in the range of 5-19%, far less than needed to keep the nation’s lakes healthy. Michigan does not track individual lake watershed projects supported with Section 319 grant funds.

Significant new funding needs to be allocated to support a coordinated effort to address the many threats to lake water quality and prevent further deterioration of existing healthy lakes.

The North American Lakes Management Society (NALMS) has been developing the elements of an advocacy campaign related to restoring funding to Section 314 of the CWA to once again allow for diagnostic-feasibility studies to be conducted on lakes across the country and to enhance the Clean Lakes Program by including funding for preservation and protection efforts for high quality waters.

NALMS recommends:

  • Congress reauthorizes funding for the Section 314 Clean Lakes Program and significantly increases annual appropriations over previous funding levels.
  • Revising the implementation of the Clean Lakes Program by adding a Healthy Lakes component to protect high quality lakes and prioritize lakes with significant cultural heritage value and lakes in communities where there are environmental justice concerns.
  • Evaluation of existing programs like Section 319 Nonpoint Source Program, Healthy Watersheds, Urban Waters and 106 Monitoring Program to identify additional opportunities to advance lake restoration and protection.

The NALMS 314 Working Group is taking the lead in developing materials to communicate with partner organizations and has engaged a college student intern for developing public outreach materials centered on the importance of the Clean Lakes Program and the value of lakes to the National, state and local economies, and the American way of life. The intent is for these materials to be used by lake advocates across the country to campaign for restoring funding to, and enhancing Section 314 of the CWA.


  • Fact sheets, brochures and other informational resources geared to stakeholder groups related to this effort, and recommendations for mobilizing stakeholders.
  • Packaged slideshows with narration for various audiences.
  • A survey for state agencies and their collaborators on what is needed at the state level if funding is re-appropriated.
  • A template letter for constituents to use in contacting their congressional representatives to express their support for re-funding and enhancing Section 314 of the Clean Water Act.

To learn more background behind the NALMS 314 Working Group efforts, visit the NALMS Enhanced 314 Clean Lakes Program position statement.

Highly Invasive Exotic Spiny Water Flea Pose a ‘Clear and Present’ Threat to the Aquatic Food Webs that Sustain our Freshwater Ecosystems

by Scott Brown

MWA e-Newsletter Editor

First observed in the waters of Lake Huron in the late fall of 1984, aquatic biologists suspect that exotic invasive spiny water flea (scientific name: Bythotrephes longimanus) entered the Laurentian Great Lakes region via the ballast water discharge of a commercial freighter that had entered the freshwater inundated North American continent after navigating from Europe. A native of the Ponto-Caspian Sea region of Eastern Europe and western Asia, the predatory zooplankton species commonly referred to as spiny water flea likely spread via currents, inter-lake ballast water transfers, and recreational boaters to Lake Ontario by September of 1985, to Lake Erie by October of 1985, to Lake Michigan by September of 1986, and to Lake Superior by August of 1987.

Characterized by a distinctive black eye spot, a single long spiny tail, and an opaque body that ranges from one quarter (.635 cm) to five eights (1.59 cm) of an inch in overall length, spiny water flea are capable of explosive rates of population growth due their inordinate capacity to reproduce asexually by cloning themselves in relatively warm waters that are present in late spring and summer, and by reproducing sexually in the cold waters of late fall by producing and fertilizing eggs that are capable of remaining viable for long periods of time due to their inherent resistance to freezing and drying.

The presence of exotic aquatic invasive spiny water flea represents a ‘clear and present’ danger to the freshwater ecosystems that they invade due to the fact that they make their living by aggressively preying upon often abundant and highly beneficial native zooplankton species such as Daphnia that serve as the primary food source for juvenile fish, and that help achieve and sustain clear water in most of our lakes by grazing upon unicellular green algae phytoplankton species that are generically referred to as diatoms. Aquatic biologists fear that declines in the abundance of Daphnia and other native zooplankton species that are heavily preyed upon by spiny water fleas will significantly alter the food web of the Great Lakes, and therefore reduce the number of young phytoplankton eating fish that are capable of surviving their highly vulnerable first year of life. Researchers have also observed that some valuable Great Lakes species such as chinook salmon, walleye, white bass, alewife, yellow perch, white perch, and lake whitefish often consume spiny water flea. It is not currently known, however, how nutritional the exotic spiny water flea is for fish, given the significant portion of the species overall biomass that is comprised of exoskeleton, and the namesake long spiny tail that are known to possess little or no value nutritional value.

The substantial threat posed to invaded freshwater ecosystems is amplified by the fact that spiny water flea deploy a highly effective survival strategy that allows them to avoid being preyed upon by migrating into deeper, cooler, light deprived waters during the day, and by returning to the upper layers of the water column to feed at night under the cover of darkness. The capacity of spiny water flea to disrupt the aquatic food webs that help sustain a myriad of fish species is also enhanced by the fact that many of the fish that inhabit our inland lakes such as bluegill and red eared sunfish are incapable of eating the highly invasive exotic zooplankton species due to their long spiny tails.

The telltale existence of the highly invasive exotic zooplankton species within a particular lake is usually initially detected by sport fisherman whose fishing rod eyelets become clogged with spiny water fleas, or downrigger cables that become inundated with the black eyed, spiny species.

In addition to becoming aware of the fact that this highly invasive exotic zooplankton species continues to spread from lake to lake in the Great Lakes region, recreational boaters and sport fisherman can help prevent the species from entering your favorite lake by remembering to ‘Clean – Drain – Dry’ before transporting their boat and trailer to a new lake.

To learn more about the Michigan State University Extension Clean Boats, Clean Waters program click here 

Elegant, and a Bit Exotic, The Only Sporadically Occurring C. sowerbii Adds A Bit of Mystery and Delight to Michigan’s Waters

Story and Photos by Scott Brown
MWA Board Member

Evoking expressions of surprise and delight, the initial experience of observing an only sporadically occurring swarm of ancient undulating freshwater jellyfish gracefully propelling themselves through the late summer warm waters of one of our wonderful inland lakes always seems to be a joyful one. Commonly referred to as “peach blossom fish” in their native China, words such as exotic, elegant, fascinating, graceful, and mysterious are often used by authors to aptly describe the ethereal freshwater jellyfish species known as Craspedacusta sowerbii that occasionally appears in the inland lakes and ponds of the Laurentian Great Lakes region.

A native of China’s Upper Yangtze River basin, the exponentially increasing pace of international trade that has occurred over the course of the past century has inadvertently led to the fact that C. sowerbii has now been observed on every continent on earth except Antarctica, and has become the most widely distributed freshwater jellyfish on earth. C. sowerbii and the nineteen other species of freshwater jellyfish are classified as hydrozoans, a class of small colonial or solitary predatory animals that are related to sea anemones and corals. Catalogued in England by naturalists in the 1880’s, C. sowerbii was first observed in Michigan waters in the 1930’s. C. sowerbii belongs to the Cnidaria, a diverse phylum of hydrozoans that contains over 11,000 marine and freshwater species whose exotic physical appearance is primarily defined by an umbrella-like radial symmetry.

Representing an extremely delicate and highly elastic gelatinous creature that is intolerant of intense wave action and fast-moving waters, the freshwater jellyfish species known as C. sowerbii that inhabits the waters of our inland lakes is most often observed floating or gracefully swimming near the surface in ponds, reservoirs, quarries, the slow-moving backwaters of rivers, and quiet wind-sheltered areas of inland lakes. Lacking a brain, heart, respiratory system, skeleton, and even blood, the relatively simple, delicate anatomy of C. sowerbii is comprised of a translucent bell-shaped outer layer known as the epidermis; a middle layer consisting of a thick, highly elastic, grayish-blue in color gelatinous substance that is referred to as the mesoglea; and, representing a simple digestive system that acts as both a stomach and intestine with just one opening that serves as both mouth and anus, an inner layer that is referred to as the gastrodermis which includes a crude stomach-like structure that is referred to as the manubrium. Circulation of nutrients within the ancient organism is facilitated by the existence of four radial canals that originate along the edges of the manubrium.

Freshwater jellyfish are known to possess a sense of smell, are able to detect light, and are capable of sensing and responding to near-by stimuli such as motion due to the existence of an elementary network of nerve cells that are widely distributed throughout their gelatinous body. The rim of their translucent bell-shaped epidermis is adorned with up to 400 relatively long tentacles that each possess thousands specialized cells called cnidocytes that are deployed by the organism to capture and pass prey consisting of tiny zooplankton to the opening of their gastrodermis. Drifting in the water column with its tentacles fully extended, jellyfish waits for suitable prey such as a tiny daphnia to come into contact with a tentacle. Once contact is made, nematocyst cells within the tentacle fire into the prey, injecting a tiny quantity of a powerful toxin that acts to paralyzes the animal, with the tentacle then acting to secure the prey by wrapping itself around the immobilized animal. It is important to note that stings by small freshwater jellyfish such as C. sowerbii produce only minor pain and often go unnoticed by swimmers due the miniscule amount of toxin that is injected as a result of contact with a tentacle. Mature C. sowerbii are capable of growing to a diameter of approximately three quarters of an inch, responding to the detection of stimuli such as near-by motion, however, the highly elastic gelatinous species is capable of instantaneously expanding its translucent epidermis to three times its normal diameter.

Beginning life as a tiny polyp attached to aquatic vegetation, rocks, or coarse woody debris, C. sowerbii and other species within the Cnidaria phylum possess a complex life cycle that allows them to expeditiously take advantage of the return of environmental conditions that are favorable to their survival and sustainability. In rare populations of C. sowerbii that possess both female and male individuals, the species is capable of achieving sustainability by alternating with each generation between reproducing sexually, with free floating sperm cells fertilizing eggs, and reproducing asexually by cloning themselves. Freshwater jellyfish are dimorphic, depending upon conditions, such as water temperature, the amount of light penetrating the surface, and/or food availability, freshwater jellyfish such as C. sowerbii are known to alternate between a polyp phase, a larval phase, and a relatively brief life in late summer as a sexually mature free-swimming male or female hydro-medusa. Freshwater jellyfish such as C. sowerbii are known to spend much more time in existence as microscopic podocysts, frustules (larvae produced asexually by budding), planulae (larvae produced sexually by mature male and female hydromedusae), or as sessile polyps that attach themselves to stable submerged surfaces such as coarse woody debris and rocks. It is important to note that the vast majority of C. sowerbii colonies are comprised of all-male or all-female individuals, therefore rendering the species almost completely dependent upon asexual reproductive processes for long-term survival.

Intolerant of the cold-water temperatures that are present in northern temperate waters in late fall, winter, spring, and early summer, the most abundant colonies of mature hydro-medusa phase C. sowerbii are observed as late summer water temperatures reach their maximum in August and September. Most often observed floating or swimming near the surface on bright sunny days, the mature hydro-medusa phase of C. sowerbii comes to an end with the gradual emergence of cold-water temperatures. During the winter months when northern temperate water bodies are frozen over, C. sowerbii contracts and enters a long period of dormancy as resting bodies called podocysts. Once environmental conditions become favorable, they again enter the polyp phase that with the gradual emergence of warm water that occurs in late summer or early fall leads to the formation of a mature hydro-medusa.

Michigan Receives $5 Million Grant to Remove Barriers to Fish Migration and to Restore Aquatic Habitat

Michigan has been awarded $5 million in grants from the non-profit National Fish and Wildlife Foundation that will be dedicated to funding removal of several dams and culverts that are the primary cause of long-term declines in many migrating native fish species due to fragmentation of critical river, stream, and creek habitat located in northern Michigan. The grant will enable local projects whose primary aim will be to restore the natural pathways and aquatic habitat that many native fish species ultimately depend upon during their life cycles for migration back and forth between the Great Lakes, for spawning, for foraging, and for protection against predation. The river and stream aquatic habitat restoration projects are also expected to benefit at risk populations of eastern massasauga rattlesnake, pickerel frog, and several species of increasingly rare freshwater mussels.

The Michigan Department of Natural Resources will manage the grant-funded projects in collaboration with local conservation groups and Indigenous tribes with an intended goal of reconnecting nearly 200 upstream miles of rivers and streams situated in fourteen Michigan counties. Rivers, streams, and creeks where the grant money will fund aquatic habitat connectivity restoration efforts include:

  • Twin Lakes Creek in Cheboygan County
  • AuSable River in Crawford County
  • Carr Creek, Dana Lake, and Little Bay de Noc in Delta County
  • Wycamp Creek in Emmet County
  • Two Mile Creek in Gogebic County
  • Boardman/Ottaway River in Grand Traverse County
  • North Branch Cole Creek in Lake County
  • Spring Creek in Luce County
  • McAlpine Creek in Mackinac County
  • Silver Lead Creek in Marquette County
  • Little Muskegon River and Buckhorn Creek in Mecosta County
  • Stony Creek in Oceana County
  • East Branch Big Creek and AuSable River in Oscoda County
  • Hayden Creek in Van Buren County

In addition to the project leadership role of the Michigan Department of Natural Resources, several groups including the Conservation Resource Alliance of Traverse City, Huron Pines in Gaylord, Little Traverse Bay Bands of Odawa Indians, Michigan Trout Unlimited, Muskegon River Watershed Assembly, Superior Watershed Partnership and Land Conservancy in Marquette, and the U.S. Forest Service are each also expected to make significant contributions to the overall success of the National Fish and Wildlife Foundation grant funded aquatic habitat restoration initiative.

A leading contributor to the fact that many native fish populations in the United States have suffered severe declines over the course of the past one hundred years, more than two million dams, culverts, and other barriers that act to prevent certain species of native fish from migrating upstream to spawn are present in the United States. The long-term effects of the many physical barriers that prevent life sustaining fish migration is best exemplified by the fact that Atlantic salmon, once present in abundance in every river north of the Hudson River, a coldwater species that seeks to spawn and raise their young in rivers, then migrates back to the ocean to feed, grow, and then again attempts to return upstream to spawn, is now a threatened species.

North America’s Diverse and Highly Beneficial Native Freshwater Mussels Provide an Array of Valuable Ecosystem Services to our Aquatic Ecosystems

Michigan’s Once Diverse and Extraordinarily Abundant Mussel
Populations Now in Severe Decline or Extinct

by Scott Brown

Snuffbox, pimpleback, white catspaw, elk toe, slipper shell, Wabash pig toe, fat mucket, deertoe, three ridge, maple leaf, and three horned warty back represent just a small sample of the hundreds of unique common names that humans have assigned over the course of the past two hundred fifty years to members of two indigenous families of freshwater mussels that inhabit North American waters. In spite of their only vaguely descriptive and sometimes amusing common names, aquatic ecologists who have observed the “flamboyant” reproductive strategies and studied the unique life cycles of freshwater mussels have suggested that the venerable creatures of the substrate represent one of our planet’s most fascinating and grossly under-appreciated animals.

The vast majority of the freshwater mussels that are indigenous to North American rivers, streams, and lakes are members of the diverse Order Unionoida, and includes two hundred eighty-six species within fifty-eight genera of the Family Unionidae, and five species representing two genera within the Family Margaritiferidae. Even though approximately one thousand freshwater mussel species within the Order Unionoida inhabit freshwater ecosystems distributed across the planet, North American rivers, streams, and lakes situated east of the Rocky Mountains continue to support at least one third of the species within the diverse Order, and therefore host the greatest diversity of freshwater mussels on earth. It is also important to note that freshwater ecosystems distributed throughout Canada and the United States, including many located within the Laurentian Great Lakes region, and especially Lake Michigan, also currently host massive infestations of two highly invasive non-native species of freshwater mussels within the Dreissena genera of the Family Dreissenidae: Dreissena rostriformis bugensis – quagga mussels; and Dreissena polymorpha – zebra mussels. Moreover, North American fresh and brackish water ecosystems also host two increasingly widespread exotic invasive mollusks within the Corbicula genera of the Family Cyrenidae: Corbicula Corbicula fluminea – Asian clams; and Corbicula largillierti – freshwater clams.

Ranging in size from three to twenty-five centimeters (1.18 – 9.84 inches), native adult freshwater mussels within the Families Unionidae and Margaritiferidae possess calcareous exoskeletons that consist of two distinctive hinged shells that are referred to as valves that provide both structure and protection to an otherwise highly vulnerable gelatinous body. A highly variable set of characteristics that include size, shape, thickness, texture, color, and pattern forming special features such as ridges, rays, chevrons, bumps, and warts that often adorn the distinctive shells of freshwater mussels serve to enable the ability of aquatic ecologists to reliably identify each species in the field. Freshwater mollusks possess a delicate soft tissue body that consists of a mouth, a relatively large stomach, a kidney, an intestine, an in-current siphon, an ex-current siphon, large filamentous gills that enable the extraction of oxygen, a foot that allows the unique creature to slowly move short distances, and remain anchored to substrates even in the presence of strong currents, and ligaments that permit the organism to open and close its surrounding shells. Comprised of neurons and glial cells that are supported by a network of connective tissue, Unionid mussels also possess a rudimentary sensory system that allows the sightless creatures to sense motion induced by nearby fish or potential predators. Representing the longest living invertebrates on earth, freshwater mussels living in optimal habitat are capable of achieving lifespans that often exceed fifty years.

The extraordinary reproductive cycle of Unionid freshwater mussels begins as sperm originating from the mantle cavity of a male mussel is ejected through their ex-current aperture, and is taken via the surrounding water column (hopefully) into a nearby female’s mantle cavity through their in-current aperture. Eggs that become fertilized move from the gonads of the female to their gills where they ripen and gradually metamorphosize into first larval stage mussels referred to as glochidia. Ranging in size from 0.05 to 0.5 millimeters, to those observing the tiny organisms through a microscope, depending upon species, mature glochidia are triangular, oblong, or circular in shape, and appear as miniature bi-valve mussels. Characterized by the presence of sensory hairs on their mantle, and either a larval thread or hook-like structure that protrudes from their partially open shell, the next stage of the reproductive cycle of freshwater mussels begins when up to one million mature glochidia are expelled by the female, and a tiny fraction of those become attached to the gills, skin, or fins of a fish that serves as parasitic host. Freshwater mussel populations located in the Laurentian Great Lakes region often rely upon smallmouth bass or walleye to serve as hosts for glochidia. Upon attachment to a compatible host fish the mature glochidia forms a protective cyst that acts as a parasite while extracting critical growth nutrients that support continued growth and development of the now fast maturing glochidia. Following a period that depending upon species ranges from ten to thirty days, the now juvenile mussel falls off their parasitic host, and enters the third and final stage of development that occurs within the substrates of the host freshwater ecosystem. Lasting from one to eight years, freshwater mussels in the juvenile stage of life complete their internal development, achieve exponential shell growth, and reach sexual maturity. It is important to note that the vast majority (99.999%) of glochidia ultimately fail to become attached to a host fish, and, due to the fact they are not yet capable of living independently in the substrates, die within hours of being expelled from their parent female mussel.

Representing an extraordinary strategy that has evolved in order to enhance an otherwise extremely low glochidia survival rate, species within the Lampsilis genera of the Family Unionidae have evolved the unique ability to deploy their mantle in a manner that bears extraordinary resemblance to the appearance of a small fish. Replete with natural looking markings and false eyes, the realistic decoy moves in the current and serves to attract the attention of fish in the area. Potential host fish that approach and attempt to prey upon the decoy are abruptly doused with a dense cloud comprised of hundreds of thousands of glochidia in the hope that a few of the tiny organisms will succeed in establishing a life sustaining parasitic relationship while attached to the gills, skin, or fins of a fish whose immune system has evolved to accommodate the presence of mature glochidia. Aquatic ecologists familiar with the reproductive processes of freshwater mussels recognize that the unique relationship that exists with fish that are capable of providing support to larval stage reproductive propagules represents an extraordinarily innovative strategy that has evolved in order to provide the sessile creatures with the capacity to successfully colonize upstream habitats. The very fact that at least small populations of approximately one thousand freshwater mussel species within the diverse Order Unionoida continue to be observed in rivers, streams, and inland lakes distributed across the planet serves as a de facto indication of the existence of aquatic habitat that is capable of supporting the ecologically sensitive creatures.

The incredible size, abundance, and diversity of populations of native freshwater mussel that were often present well over a century ago in many North American rivers strongly suggests that optimal habit for members of the Family Unionidae and Family Margaritiferidae is primarily found in large northern temperate rivers whose sensitive aquatic ecosystems are protected from the negative influences of their surrounding watersheds by forests, marshes, wetlands, and densely vegetated riparian corridors. The capacity of large northern temperate rivers to support abundant freshwater mussel communities is ultimately contingent upon the existence of relatively high quality aquatic ecosystems whose continuously flowing pollution and sediment free waters are capable of supporting much higher dissolved oxygen content in contrast to the still waters of inland lakes and ponds, for example, and healthy, moderately productive littoral zones that are capable of providing filter feeding mollusk communities with an abundance of the phytoplankton, diatoms, and other tiny organisms that they depend upon for sustenance. Moreover, due to their glacial origins, the waters of many large northern temperate rivers are also capable of providing the abundant calcium carbonate concentrations that freshwater animals such as mollusks and snails rely upon for the development of their protective shells. Northern temperate rivers that have maintained their capacity to support abundant freshwater mussel populations are also characterized by host fish friendly benthic habitat such as woody debris, boulders, and stones, as well as by natural shorelines, and near shore shallow areas featuring abundant emergent aquatic plants that provide optimal habitat for juvenile host fish. It is important to note, however, that certain members of the Family Unionidae and Family Margaritiferidae exist only in northern temperate inland lakes, streams, and small rivers characterized by slow moving or still waters. The freshwater mussel known as lake floater (Pyganodon lacustris), for example, is primaily observed inhabiting substrates that are situated in wind and wave protected coves and bays of inland lakes. Given the fact that native mollusks are capable of living for periods of up to fifty years, the existence of abundant and diverse freshwater mussel communities accompanied by large quantities of the abandoned shells of previous generations serves as a reliable bio-indicator of the long-term existence of habit conditions that were ultimately capable of supporting the ecologically sensitive bell weather species.

Native freshwater mussels are powerful ecosystem engineers that are capable of rendering highly beneficial ecological services that contribute to achieving and sustaining healthy, diverse aquatic ecosystems. First and foremost, freshwater mussels are highly efficient filter feeders that are perhaps best known for their extraordinary collective capacity to transform turbid, light deprived waters into relatively clear waters by removing algae, bacteria, suspended particulate, and organic matter, allowing life sustaining sunlight to penetrate deeper into the water column, and enabling highly beneficial submerged aquatic plants to colonize larger, deeper areas of the ecosystem. The propensity of freshwater mussels to filter out and utilize suspended algae, inorganic particulate, and organic matter also enables the capacity of the unique substrate-borne creatures to effectively sequester phosphorus, nitrogen, and carbon that would otherwise be available to fuel exponential growth of light attenuating phytoplankton. Freshwater mussels also contribute to sustaining a host of other ecosystem-friendly creatures by converting filtered materials into important sources of food that would otherwise be unavailable for consumption by the myriad of fish, crayfish, amphibians, reptiles, birds, and mammals that often forage within aquatic ecosystems. Diverse in size and shape, the durable abandoned shells of freshwater mussels that have completed their life cycles also provide protective physical spaces that serve as optimal benthic habitat for aquatic insects, and nesting sites for small fish.

Once abundant freshwater mussel communities are also known to have made significant contributions to sustaining North America’s indigenous tribes in centuries past, and in particular the mound-building tribes of the Midwest who placed a high value on the shells of the substrate-borne creatures that were efficiently utilized for making tools, jewelry, and pottery, and upon their meat that was considered an important source of protein rich food. In sharp contrast to the responsible and ultimately sustainable manner in which North American indigenous tribes utilized freshwater mussels to support their culture for many centuries, large scale commercial exploitation of the extraordinarily abundant populations of freshwater mussel that once existed in many of North America’s large rivers, and particularly the Illinois, Columbia, and Ohio Rivers, did not begin until the late 19th century. Recognized by textile entrepreneurs of the time for the considerable economic value of their pearly, durable shells that were turned into the tens of millions of buttons of various sizes that were in demand by a flourishing garment industry, freshwater mussels were removed en masse from the ecologically sensitive substrates of rivers distributed across North America between 1890 and 1950 in order to support the two hundred button factories that were in operation during the period. Large scale, grossly unsustainable exploitation of freshwater mussel populations in North America lasted for well over half a century, and ended only in response to the advent of plastic that than become a cheaper, and much more readily available source of durable material for manufacturing buttons in the early 1950’s.

Coupled with the historically significant fact that extraordinarily diverse and abundant native freshwater mussel communities that inhabited many large North American rivers were being exploited for their valuable shells at an unsustainable rate, the rampant pace of industrialization that was also occurring on much of the continent within the late 19th and early 20th centuries was driving equally unsustainable rates of deforestation that ultimately caused the permanent loss, and/or severe degradation of freshwater habitat that was capable of supporting the ecologically sensitive species such as freshwater mussels has also been caused by the fact that many large rivers have been extensively dredged to allow their once relatively shallow channels to accommodate large commercial cargo vessels that are now deployed to transport coal, iron ore, and other heavy industrial commodities. Not surprisingly, large North American rivers such as the Ohio and Illinois are now widely recognized as the most extensively polluted rivers in the world.

The extent of the loss of freshwater habitat that was once capable of supporting abundant and diverse freshwater mussel communities in North America is best measured by the fact that up until the early decades of the 20th century the substrates of many large rivers such as the Ohio, Columbia, Illinois, and the Wabash “were paved with mussels.”  Loss of freshwater habitat that is capable of supporting abundant freshwater mussel populations has unfortunately continued at a steady pace for well over one hundred years. For this reason, readers should not be surprised to learn that nearly three-quarters of North America’s once extraordinarily abundant native freshwater mussel species are now classified as endangered, threatened, species of special concern, or, as in the case of as many as thirty-eight ecologically sensitive species, have now passed into extinction.