Issues Forum - Fall 2008

At each Annual General Meeting of the Canadian Wildlife Federation, we hold an “Issues Forum.”  This is a time when experts are invited to present on various topics to keep CWF staff and its Board current on issues impacting Canada.

This year’s meeting was no exception. With speakers presenting on polar bears, Alberta’s oil sands and different management strategies for chronic wasting disease, there was a wealth of knowledge that we would like to share with you.

Great Lakes Water

Dr. Jim Sherry, Project Chief of Ecosystem Health Assessment with Environment Canada gave an excellent presentation on Great Lakes water quality as well as issues impacting wildlife in this system.

The Great Lakes, a system of water bodies shared between Canada and the United States, are highly important and are a system we can not take for granted. The Great Lakes make up the largest group of freshwater lakes in the world and comprises 22% of the world’s freshwater. They provide habitat for approximately 350 species of fish and are the source of drinking water for 40 million people. They also act as a very important transportation route.

Prior to the arrival of western man, the Great Lakes boasted a healthy and biologically diverse flora and fauna with productive and balanced fish communities.

However, with the arrival of western man also came stresses on the Great Lakes. Stresses such as unregulated harvests of fish species, commercialization of the waterways and ecological assault from activities such as forest clearance, urbanization, intensive farming and waste discharges.

The result of some of these activities has lead to the acceleration of a natural process called eutrophication. This causes an increase in nutrient loading which leads to the depletion of oxygen resulting in either death or population shifts in organisms.

It has been stated that the St. Lawrence Seaway and the various man-made interconnecting waterways, such as the Erie Canal, have done more damage to the Great Lakes ecosystem than all of the other stressors combined. One such consequence of shipping traffic has been the introduction of many non-native species, many of which have become invasive. One needs to look no further than the damage that the sea lamprey has caused to lake trout.

Legacy contaminants continue to impact the Great Lakes and its wildlife, although their effects are diminishing with time. Legacy contaminants include dioxins, PCB’s and DDT. The impacts of these contaminants on wildlife are many but include reproductive failure in fish and deformities, eggshell thinning and reproductive failure in birds.

Dr. Sherry’s research is looking at the presence of a yolk protein in fish that causes feminization. He is finding that there is a significant increase in the concentration of this egg yolk protein in fish from certain areas of the Great Lakes.
 
Other substances that are found in the Great Lakes include:

• synthetic estrogen from birth control pills where enough is being released into the environment to cause reproductive failure,
• carbamazepine – an anti epileptic drug,
• road salt which may be a threat to the recovery of endangered mussels,
• flame retardents which have been found in high concentrations in the Great Lakes
• Triclosan – a chemical found in shampoo and causes transformities in frogs.

The results of this presentation are pretty alarming and demonstrate that we all need to work together to lessen our environmental impacts. Reducing fertilizer use, treating sewage waste and eliminating phosphates from laundry and other detergents are a few actions that we can take to start reducing our impact on the Great Lakes and other water bodies. Not only will wildlife benefit but so will we! 

Baiting Cervids

Ken Rebizant, Big Game Manager for Manitoba Conservation was invited to present on the impacts of baiting on cervids.

Baiting is the placing of feed to attract animals. For this presentation, Mr. Rebizant limited the impacts to deer and elk.

Baiting results in:

• The concentration of animals
• Increases animal to animal interactions
• Can foster feeding on agricultural crops
• Can function to increase the spread of diseases.

The number of animals that are attracted to a baiting station varies from only a few individuals to several hundred, depending on the conditions. Bait and feed often become contaminated by the animals at feeding stations as saliva, urine and feces fall to the ground. This results in a favourable environment for the spread of disease. In addition, sick animals typically spend more time at bait sites in comparison to healthy animals.

For Manitoba Conservation, the diseases they are concerned with in regards to baiting are Chronic Wasting Disease and Bovine Tuberculosis.

For CWD, transmission is through both saliva and blood with suspected transmission through feces and urine. In regards to Bovine TB, it is transmitted through saliva and respiratory mucus. The transmission routes for both of these diseases are common at baiting stations.

Because of concerns such as disease spread, Manitoba has prohibited the use of baiting for deer and elk since 1992 with feeding bans in some parts of the province and an overall discouragement of the activity province wide.

Different provinces in Canada have different perspectives on baiting. While British Columbia is considering a ban, Saskatchewan allows the practice of baiting and feeding.