Yellowknife (Feb 06/04) - An Alberta insect expert says trying to control mosquitoes in Yellowknife could be a waste of time.

Chris Saunders, biological sciences technician working for the City of Edmonton, was in Yellowknife two years ago to help the city in its efforts to eliminate the birch leaf miner.

He remembers flying over the city and thinking to himself that there was no way the mosquito control efforts they use in Edmonton would work here.

"I would say immigration from your wetland areas surrounding Yellowknife would make it almost a waste of time doing anything," said Saunders, noting that mosquitoes can fly 25 kilometres in a single night.

Outside Edmonton and in roadside ditches along freeways, they spray standing water and ponds with Chlorpyrifos -- a nerve agent that kills larvae. In residential areas, they drain sloughs or fill them with BTi -- a bacterial agent that kills the larvae after they eat it.

He said likely the only option available to Yellowknife would be to drain standing water areas where possible and hope for a dry winter.

NWT chief medical officer Dr. Andre Corriveau said there has been a lot more interest in mosquito control in recent years because of fears over the West Nile virus. From what he's heard, there have been great improvements in mosquito control agents, but he also doubts they would be of much use around Yellowknife.

"Some of the products used have been found to be extremely safe, but not all are that effective," said Corriveau.

"If you have a few localized pools where mosquitoes breed you can easily deal with them, but if you have pools everywhere my gut feeling is they wouldn't be very useful."

He and Saunders doubts West Nile virus could ever thrive in the North.

"You need at least two weeks of temperatures above 14 C every night, which we hardly ever get," said Corriveau.

Mosquito not found here

Saunders' chief responsibility is to monitor insect infestations. He said the mosquito that carries the virus in Western Canada, from the genus culex species, needs open grass and parklands to survive.

He said only one species -- culex tarsalis -- has been found in Alberta to date, although other culex members are known to carry the disease elsewhere in North America.

Saunders was in Red Deer, Alta., Tuesday, attending a province-wide meeting of municipalities regarding the spread of West Nile virus.

He said the participants were in general agreement that it likely won't spread to forested regions of the province to the north.

"It's not in the boreal forests as far as we can see so far," said Saunders.

"Distribution-wise I can't see it getting as far as Yellowknife."