Report: Protecting Lake Huron

Lake Huron is in “fair” condition according to a technical report analyzing the health of Lake Huron, released by the Nature Conservancy of Canada in November. The report, titled The Sweetwater Sea: An International Biodiversity Conservation Strategy for Lake Huron, took a team of 400 individuals from over 100 agencies and organizations two years to research and write.

Traditionally, Lake Huron is considered separate from Lake Michigan, but is technically the same body of water, and certainly one of the largest bodies of freshwater across the globe. The Great Lakes contain 20% of the world’s freshwater and are considered by many as the crown jewel of the United States. Although the report looks only at Lake Huron, the challenges faced in protecting it are shared by all of the Great Lakes and by water bodies throughout the world.

Included in the report are what the group considers the most critical threats to Lake Huron, such as non-native invasive aquatic and terrestrial species; housing / urban development and shoreline alterations; climate change; dams and barriers; and agricultural, forestry and urban non-point source pollution. The report also includes information regarding strategies to combat the most critical threats, protect biodiversity and clean-up the lake – not only to protect human health, the environment and recreation, but also the economy.

Invasive Species Are a Critical Threat

According to the report, “Invasive species threaten the diversity, abundance, and long-term viability of native species and the ecological stability of Lake Huron,” and can have a significant impact upon the physical, chemical, and biological characteristics of the lake. Although there are management plans in place for some of these non-native creatures, including fish, invertebrates, plants, algae, and pathogens, the report explains that, “Once established, it is extremely costly to manage and remediate their impacts…Eradication is rare,” and “…respective impacts of established invasive species population as largely irreversible.” Furthermore, it is difficult to manage invasives because it is an international affair and very difficult to address some of the, “global economic forces.”

Housing and Urban Development and Shoreline Alteration

Increased development and vehicular traffic along the shoreline of Lake Huron is having a significant effect upon the health of the lake by destroying habitat, introducing chemicals, nutrients and sediments into the lake. Also, due to low water levels land owners are altering the shoreline for boat access by dredging, filling, and building barriers to try to increase water levels. Moreover, this development is destroying wetland and dune ecosystems. It seems one of the major impediments to remediate the problem is that sometimes there is a general “lack of understanding and clarity” regarding shoreline jurisdiction and water rights. According to the text, an additional obstacle is that, “current policies are too permissive in their approval of development projects” and often do not consider cumulative impacts.

Climate Change

The report also mentions climate change as a major threat to Lake Huron. In sum, the major changes from global warming will include increased air and water temperature, changes in seasonal patterns, changes of wind and water patterns, as well as changes in lake levels and ice cover. One of the greatest challenges is that the effects of climate change aren’t easy to predict, and because it is happening so quickly species will likely not be able to adapt – resulting in a number of reproductive issues, population declines, and sometimes extinction.

Dams and Barriers

Dams and barriers are defined in the report as, “anthropogenic structures that alter the hydrology of tributaries,” including road crossings as well. Altering tributaries can impact fish habitat for spawning, nursing, overwintering, and migrating by eliminating connections between the lake and its tributaries. The document highlights that “86% of major tributaries are no longer connected to the Lake Huron basin,” and that, “This loss of tributary habitat has resulted in significant declines in native fish populations in the lake…” In addition to nursing and spawning grounds for fish, tributaries also, “provide water, nutrients, and sediment to Lake Huron and its coastal and nearshore ecosystems.” One of the challenges to ameliorating this problem is that some barriers help to contain invasive species and keep them from spreading to other freshwater bodies, “Hence, decisions about removal of dams and barriers in Lake Huron must balance competing interests and goals, which may not always be explicit.”

Non-point Source Pollution

According to the report precipitation moves across the land and picks up harmful contaminants, sediments, and nutrients and introduces them into water bodies, which can degrade water quality – known as non-point source pollution. Much of this pollution is caused by human activities such as, agriculture, urbanization, or forestry which can result in “concentrations of septic systems, lawn fertilization, construction, impervious surfaces, and land drainage.” Not knowing the starting place of pollution makes it especially difficult to address the problem. And, according to the document, this type of pollution “is generally considered to have higher irreversibility that is not practically affordable in many circumstances.”

Considering the serious threats and that 20% of the world’s freshwater resource is at stake, the report does not have an ominous chicken little feel about it, but it does end with a serious call for action, explaining that this report “is just the beginning of an urgent and important journey, and this first step will only be as meaningful as potential implementers make it through their actions…Achieving lasting conservation of Lake Huron’s biodiversity requires the ongoing attention and action of everyone that has participated in this process, and many more.”

The full technical report can be accessed at The Sweetwater Sea: An International Biodiversity Conservation Strategy for Lake Huron; click here for a summary report.