Oak Hammock Marsh - and our knowledge of wetlands

While in the Interlake today I stopped in to visit Oak Hammock Marsh. It is an example of a wetland restored. On its shores are the headquarters of Ducks Unlimited Canada. The interpretive centre at this site is a valuable opportunity to learn more about marshes.

Did you know that 14% or 127 million hectares of Canada's surface area is in wetlands - and that this makes up 25% of the world's wetlands? Clearly we have an important national need to understand wetlands well.

In Manitoba this is particularly true. Much of southern Manitoba is prone to flooding. Did you know that areas with 15% of their surface area as wetlands can have flood peaks which are 60% lower than similar areas with no wetlands? In many hearings that I have attended during the last decade, people have spoken of the importance of a balance in activities to retain water in wetlands as well as in draining water to improve agricultural potential.

The duck tunnel shown in the third photo from the top is interesting in this perspective. Today, the success of ducks nesting on the ground is said to be 15-30% (in a note along one of the trails, it says less than 10%), while the success of ducks nesting in the tunnels like this one is said to be greater than 80%. Part of the reason for the low success of ducks nesting on the ground is because agricultural cultivation has reduced the available nesting cover around sloughs and other wetlands making it easier for predators like foxes to find the nests. The use of human built duck tunnels thus helps to compensate for other human activities which are less beneficial to ducks.

For more about Ducks Unlimited go to: http://www.ducks.ca/aboutduc/locations/index.html