It has been nearly four decades since Dr. David Schindler first published his aerial photo of Lake 226, showing the effects of phosphorus on algae growth. The now iconic image of the lake’s bright green water convinced both Canadian and U.S. governments to take action to reduce our use of the phosphates that comprise the algae’s food. But in spite of these steps, algal blooms continue to plague our freshwater lakes and in a 1999 study, Drs. Marco Janssen and Steve Carpenter showed that even without new sources of phosphorus there is enough phosphorus currently stored in lake sediment to constitute a “phosphoric time bomb” waiting to go off. That, in conjunction with the availability of atmospheric nitrogen creates what Dr. Kathryn Cottingham, professor of biology at Dartmouth College and the speaker at the 2012 annual David Schindler lecture on March 15, calls a Pandora’s box, and she and her team of researchers think they know who (or what) is holding the key.

“This is my favourite critter,” laughed Professor Cottingham pointing to the image of a tiny tentacled colony of Gloeotrichia echinulata or “Gloeo” as it is nicknamed. “It’s not only pretty when it’s alive, but it’s even kind of pretty when it’s dead,” she observed. But the eerie beauty of this organism belies the danger it poses. Gloeo is just one of several cyanobacteria that Prof. Cottingham and fellow researchers believe are working hand-in-hand with humans to intensify the eutrophication (introduction of nutrients such as phosphorus and nitrogen) of lakes, creating the ideal conditions for algal blooms. “Nitrogen in the atmosphere is extremely hard to access, but cyanobacteria like Gloeo have properties that allow them to tap into sediment phosphorus and atmospheric nitrogen which would normally be locked up, and make them available in the water column for other organisms,” explained Prof. Cottingham. “Cyanobacteria are the biotic key to this Pandora’s box.”

At idyllic Lake Sunapee in western New Hampshire, Prof. Cottingham and a team of researchers including colleagues, students, homeowners and cottagers, work together to study Gloeo and its effect on the lake, which experienced its first algal bloom in 2005. “Citizen scientists” like Midge Eliassen – a homeowner who has collected water samples from the lake every day for the past four years, and whose grandchildren now join in her efforts - are integral to the project. Prof. Cottingham lauded the members of the Lake Sunapee Protective Association, which represents local homeowners and cottagers. “This is a partnership,” she maintained. “They have done amazing things in terms of water monitoring and testing, but also in terms of local regulations like changing building codes in many of the different municipalities around the lake. They are an incredible resource.”

Unlike Pandora, however, researchers have found little hope at the bottom of this box: “We think that cyanobacteria may make it harder to restore the lakes, and moreover, controlling nutrient loading may not be enough if cyanobacteria keeps the box open,” concluded Prof. Cottingham. “There’s a lot of reason to be concerned.”

Chris Appleton, treasurer of the Kawartha Lakes Stewards Association, and Ron Brown, lake steward for Lovesick Lake were just two of the many cottagers, homeowners, and local water-association representatives who joined students and faculty, filling the 200-seat hall to near capacity. Like the “citizen scientists” at Lake Sunapee, they work closely with Trent University’s Paul Frost to study and monitor regional lakes. Growing up on Sturgeon Lake, Mr. Appleton knows the history of algal blooms in the area from first-hand experience. “I used to see it all the time when I was a kid, then they cleaned up a lot of the sewage treatment out of Lindsay which goes right into the lake and it got a lot better. But the algae was back with a vengeance last year. It was as bad as I’ve ever seen it,” he maintained. “It’s discouraging,” he shrugged, “but for me it always comes back to what are you going to do about it? What we’re going to do about it are the same things we have been doing – you naturalize the shoreline, you keep the cows out of the creek, you manage stormwater runoff from the cities… We just have to keep pounding away at it.”

“For the Sake of Our Lakes” is hosted by Dr. Paul Frost, the David Schindler Professor in Aquatic Science at Trent. Established in 2008, the David Schindler Endowed Professorship in Aquatic Science is the first-ever endowed professorship at the University, valued at $1 million. The endowment was given to the University by an anonymous donor who wished to honour the work of Dr. David Schindler, a former Trent professor and one of the world’s leading limnologists (a specialist in the study of freshwater lakes and rivers).