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. Canada's mosquito capital turns over new leaf in bug wars
OTTAWA (AFP) Jun 02, 2005
A city in central Canada infamous for its abundance of mosquitoes that daunt even the hardiest outdoor enthusiasts is turning to new chemical-free ways to de-bug its parks and backyards.

The city of Winnipeg is planning to drop minnows and dragonfly eggs into ponds where mosquito larvae hatch, expecting they will eat them, to test whether nature can be as effective as chemicals used since 1969 to curtail the bug population.

"Minnows and dragonfly larvae are natural predators of mosquito larvae," said the city's insect control spokesperson Blake Scott. "So, it makes sense to use them to try to reduce the number of mosquitoes in the city."

Each year, hundreds of thousands of people in this province dotted with copious marshes and lakes are repeatedly bitten by the pests.

According to humorists, every spring the local airport hires a dozen extra air traffic controllers to handle the influx of mosquitoes. Some even believe the bug should be named the official provincial bird.

But, what was once a mere nuissance has now become a serious health concern as killer mosquito-borne West Nile virus spreads throughout western Canada. Symptoms of West Nile virus range from fever, headaches and fatigue to brain inflammation that can lead to paralysis, coma or death. Canadian health officials reported 1,754 cases and 34 related deaths since 2002.

So, efforts to clean the air have been stepped up.

In the past, insect control crews rolled through city streets in heavy trucks fogging parks and backyards with chemicals to control the mosquito population. Area ponds and ditches where standing water collects were dilluted with chemicals to kill larvae. And, even a small airplane equipped with sprayers once bombed the pests from above, leaving clouds of chemicals in its wake.

But, an increasing number of protests against the use of pesticides forced officials to rethink these old strategies.

Residents, angry that they were being exposed to chemicals linked to cancer and other ailments, demanded that their lawns and gardens not be sprayed. This left a patchwork of properties where mosquitoes could thrive, making fogging less effective in controlling the mosquito population.

Initial tests showed that predators do as good a job as chemicals in controlling mosquito populations, Scott said.

Colder weather has helped keep mosquito populations low this year too, but next week another batch of eggs are expected to hatch across the city.

Officials hope to ramp up the program over the next three years, testing new biological agents to kill larvae, such as bacillus thuringiensis israelensis or BTI and methoprene. In that time, the insect control department's annual budget is expected to triple to nearly 6.5 million dollars (5.2 million US dollars) as it implements more environmentally friendly strategies.

Officials will also continue to urge residents to spill standing water on their property, clean bird baths weekly, dump water out of potted plant saucers and cover rain barrels with tight-fighting lids. Since half of mosquitoes come from backyards, these simple measures are extremely important to help curb the mosquito population, Scott said.

All rights reserved. 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.

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