Missing mosquitoes point to bigger problems: biologistWhile annoying to campers bugs indicate a healthy, thriving ecosystem
Northern News Services
Tuesday, August 4, 2015
For those who love spending the summer outdoors, having fewer mosquitoes around is a welcome improvement. However, for environmentalists, the missing insects throw up a number of red flags and are an indication of climate change.
Yellowknifer John Yap swats a mosquito away at the city skatepark Monday. Mosquito populations across Western Canada are a fraction of 2014 numbers. Scientists cite climate change, drought as contributing factors. July 31, 2015. - Meagan Leonard/NNSL photo
Mike Jenkins, aka "the bug guy" - is a biological sciences technician for the City of Edmonton and has been focusing most of his efforts lately on studying mosquitoes. He says in Alberta the populations are a mere one per cent of the numbers experienced in the province in 2014 and the trend extends to the NWT.
"In Yellowknife, the primary driver of the mosquito population is precipitation," he explained. "It's been a dry summer for most of the region."
Jenkings explained because the species of mosquitoes living around Yellowknife require water to hatch, many eggs are laying dormant in the drought.
"The female lays her eggs on the edge of a moist pond or area and then the water rising up at a later time either from snow melt or rainfall and activates the eggs."
Although Jenkins says mosquito eggs can remain dormant for up to 10 years during a drought and hatch later on, they don't stand a chance during a wildfire.
"They're really well-adapted to drought, but I don't think they're terribly resistant to fire," he said, referring to the eggs.
"Wildfires moving through those areas could actually reduce mosquito populations in subsequent years because it would take out the eggs."
Wildlife biologist for the Department of Environment and Natural Resources Suzanne Carriere reiterated Jenkins' concerns and said although the GNWT does not collect mosquito data to the extent Alberta does, the department has noticed populations declining and the impacts it is having on other wildlife.
She said because many birds and bats survive almost exclusively on flying insects like mosquitoes, it means they are struggling to find food.
"Birds that feed on insects . are in decline," she said. "Like swallows and the common nighthawk that flies around with its mouth open."
A warming North and cooling south also means birds are waiting longer to migrate north in the spring and missing the time when mosquitoes would be most prevalent. In the spring, many young birds come north to take advantage of the mosquitoes hatching.
"If they arrive too late compared to the peak of their food - like mosquitoes - then they don't do as well," she explained. "It's called the mismatch theory. It's not warming up as fast down south and they're taking their time to come North, by that time summer has arrived earlier than they would have predicted."
Jenkins and Carriere said caribou herds can also be affected by bug behaviour.
"Caribou move through the tundra so they're facing the prevailing winds to keep down the number of mosquitoes," he explained. "If there were no mosquitoes, then it could actually change the routes of caribou migration."
Ultimately, Jenkins said declining mosquito numbers is an indicator of a much larger problem.
"The drought stress on our forests is a bigger concern than the number of mosquitoes," he said. "There's also lots of other pest species like caterpillars and grasshoppers that are thriving in these conditions and those are more difficult to deal with."
From her perspective, Carriere says abundant numbers of mosquitoes indicate a healthy environment and ecosystem.
"Nobody should complain if there's lots of mosquitoes," she said.