A collaborative study by researchers at Queen’s University, l’Institut national de la recherché scientifique (INRS), and Brock University has determined that a nuisance algae found in Canadian rivers and lakes may be a result of global climate change on aquatic ecosystems.
This debunks original assumptions that the algae species, commonly known as didymo or “rock snot”, found its way to various rivers in Eastern Canada through human introduction.
That original ‘human-transfer’ theory resulted in several U.S. states banning felt-soled fishing boots, as it was suspected they may have facilitated the transportation of didymo between rivers.
“Didymo has been present in the regional algal community for much longer than many people thought. Instead of human introduction, an environmental trigger is a more probable cause for its recent proliferation,” said Michelle Lavery, the study’s lead author, in a Queen’s news release.
Lavery, who began her research as an undergraduate thesis student at Queen’s University, is currently completing her Masters at the Canadian Rivers Institute at the University of New Brunswick.
The earliest official report of Didymo – thick, woolly mats of algae that can affect both water recreation and river & lake food sources for fish – was in the Gaspésie region of eastern Canada in 2006. It has now been found in over 25 river ecosystems in the region.
This new research indicates that climate warming, which accelerated here beginning in the 1970s, may have created favourable conditions for the growth and spread of didymo.
“This is yet another example of the harmful effects of climate change,” said John Smol, study researcher, biology professor at Queens’s and Canada Research Chair in Environmental Change. “Too much of any algae can be a problem. For areas in Quebec and New Brunswick that are world-renowned for recreational Atlantic salmon angling, didymo blooms may lead to undesirable ecosystem effects.”
The study, funded by the Atlantic Salmon Conservation Foundation and the Natural Sciences and Engineering Research Council of Canada, has been published in the Canadian Journal of Fisheries and Aquatic Sciences (CJFAS).
Additional reading: International Didymo Conference (March, 2013)