Managing a Great Lake is no small task

[Spiel]

Managing a Great Lake is no small task

 

 

November 26, 2009

Craig Gilbert / www.midnorthmonitor.com

 

 

Managing the many faces of the great Lake Huron is a "very challenging undertaking," but someone has to do it.

 

Greg Mayne is a scientist with Environment Canada. On October 27, he opened the Friends of the Spanish River Area of Concern update symposium with a presentation on the bigger picture: The North Channel, Georgian Bay and Lake Huron.

 

According to Mayne, Huron features four distinct geological attributes: the forests of the North shore, the plains to the south, Georgian Bay and the North Channel. He displayed photos illustrating the physical beauty of each area.

 

Lake Huron is the third-largest freshwater lake in the world, containing about 3,540 cubic kilometres of water. Can you imagine an ice cube a kilometre across, tall and wide? Can you imagine 3,000 of them in once place? At 36,000 kilometres, its irregular coastline is the longest on the globe for a freshwater body. The lake's watershed is approximately 134,000 square kilometres in area.

 

"(But) the population around the lake is minimal compared to Lakes Ontario or Erie, so it is in relatively good condition," Mayne said.

 

In 2002, a bi-national agreement to take care of the lake was endorsed by the governments of Canada and the United States.

 

According to the US Environmental Protection Agency's website, "the Lake Huron Binational Partnership effort focuses on pollution reduction activities in areas of obvious importance, such as Areas of Concern (AOCs), and directly pursues on-the-ground activities to protect areas of high-quality habitat within the Lake Huron basin. Existing stakeholder and agency forums are used as much as possible to support the goals of the Partnership. The Partnership maintains a close association with the Remedial Action Plan efforts in AOCs, the Great Lakes Fishery Commission's Lake Huron Technical Committees, the State of the Lakes Ecosystem Conference (SOLEC), and domestic efforts that support the Partnership."

 

The 2008-2010 action plan provides updated information on environmental trends, identifies priority issues, and promotes management activities to be pursued over the next two-year cycle. Consistent with an adaptive management approach, the action plan tracks progress on issues identified in the previous cycle, including contaminants in fish, changes in food web structure and protection of critical habitat. It has been expanded to address emerging issues, such as observed increases in near-shore algae and diseases such as botulism and viral hemorrhagic septicemia (VHS).

 

According to Mayne, contamination levels in lake trout in Lake Huron have been steadily decreasing, but are still triggering fish consumption advisories. He said about six per cent of the problem is mercury and the rest is generally PCBs (94 per cent).

 

Biodiversity changes are also a "pressing issue" for scientists studying Huron. Traditional predators such as walleye, trout and burbot are being replaced at the top of the food chain by introduced species such as Chinook salmon and the sea lamprey.

 

There have also been "very significant changes at the bottom of the food web," according to Mayne. There has been habitat loss as wetlands are drained and in-filled, and the hydrology of rivers feeding into Lake Huron is changing; spawning areas are being clogged with zebra mussels, and human development has increased 85 per cent since the 1980s.

 

 

"There are six areas of concern in Lake Huron," Mayne said. "There have been significant declines in the forage base for many species, such as the smelt and the round goby."

 

The diporeia (a type of zooplankton) density for example, has dropped 93 per cent in the past seven years.

 

"This is an astounding finding with significant repercussions," he said. "The quagga (similar to the zebra) mussel density has gone up from zero in 2000 to 'lots' in 2007, (so there is an inverse relationship between the two). The number of fish-eating birds has been increasing since the 1970s. The levels of PCBs in gull eggs sampled in three locations have been on a steady decline, but the concentrations of other chemicals are on the rise."

 

That said, the quality of the wetlands throughout the North Channel, according to Mayne, surpass that of many others in the Great Lakes basin.

 

A new framework focused on Georgian Bay is designed to engage towns and cities around the water body in its conservation. Incorporating conservation into a municipality's official plan is one example: environmental concern by design.

 

"It is all about mobilizing the local communities around pressing environmental issues," Mayne explained. "As opposed to top-down, it's very grassroots. We want to integrate the interests of different communities in a collaborative way. It strongly promotes local restoration and protection initiatives."