Toxic algae blooms seem to occur earlier, more often: Ducks Unlimited Canada

One of North America's biggest conservation groups says toxic algae blooms seem to be happening earlier and more often.

Ducks Unlimited Canada says it's putting additional effort into protecting Alberta wetlands from nutrient-rich runoff that can help trigger blue-green algae blooms.

"Because of a number of factors, including land-use change, we're seeing an increase in the number of algal blooms and the timing," said Tracy Scott of Ducks Unlimited Canada.

Scott says climate change has also played a role as blooms are more likely when there is low snowfall and early spring warming.

Ducks Unlimited Canada restores between 240 and 365 hectares (600 to 900 acres) of wetland a year in Alberta and says it's increasingly planting more trees and other plants to help slow down the flow of fertilizer and manure into prairie potholes.

Blue-green Algae are naturally occurring but can take over a water body when helped by things such as early warm periods, low snowfall and high nutrient content.

"People don't think about blue-green algae as ecosystem engineers, but the weird thing is, they kind of self-propagate by doing this," said Dr. Rolf Vinebrooke, a professor at the University of Alberta who teaches courses on algae biology.

Vinebrooke says by using up the oxygen in a water body, the algae also release phosphorous from the lake bed – further stimulating the growth of the algae and killing off most other life.

"So they're kind of propagating themselves by producing these dead zones," Vinebrooke said.

While the blooms are a natural phenomenon, they can sometimes release a neurotoxin that cannot be made safe by filtering or boiling the water.

It can cause serious illness and even death in humans, pets and wildlife.

"What we want to do is to reduce the amount of excess nutrients running off the surrounding landscape and entering in and creating that environment," Scott said.

Research is underway to measure the problematic blooms over time using historical satellite imagery combined with analysis on the ground.

Vinebrooke says that while many in the field agree blooms are happening more frequently and earlier in the year than in the past, the data set to support the belief is full of gaps.

Researchers are now beginning to go back into satellite images from the 1990s, sometimes taken every two days.

By comparing those images to on-the-ground analysis of current outbreaks, scientists are getting close to building a reliable data set to better understand what may have changed and why.

There have been 49 public warnings for the toxic blooms in Alberta so far this year.