Climate — not development — caused algae on Huntsville’s Penlake: study
Climate was the culprit behind blue-green algae blooms on Huntsville’s Peninsula Lake, according to a consultant report.
Huntsville Forester
Tuesday, October 20, 2020
Climate was the culprit behind blue-green algae blooms on Huntsville’s Peninsula Lake, according to a consultant report.
Huntsville Coun. Nancy Alcock, chair of the District of Muskoka’s community and planning services committee, told her fellow district council members on Oct. 19 that Hutchinson Environmental Services had confirmed the result through its vulnerability causation study of the lake.
“This looked at the (impact) of ecology, climate and development on the re-emergence of blue-green algae blooms,” said Alcock.
The report, she said, stated that the study into blooms that emerged in 2017 found they were most likely caused by high air temperatures combined with low winds.
“There was no indication of a link between development on the lake and the 2017 algae blooms, and that was apparent in the data,” said Alcock.
The report, however, reiterated the importance of continued reduction in fertilizer use, continued revegetation with native species, continue water sampling and continued stormwater management.
“This all continues to be critical for the ongoing health of our lakes,” added Alcock.
Peninsula Lake is one of 12 across Muskoka identified as vulnerable by the District of Muskoka.
Algae Study - Peninsula Lake
By Wendy Somerville Fall 2019
As I’m sure most of you remember Peninsula Lake had an algae bloom in August 2017. It was a cyanobacteria by the name of gloeotrichia which was capable of producing toxins. Luckily no toxins were detected. These toxins are released when the bacteria die, so testing continued until late in October and there were still no toxins detected. Very little is known about why algae blooms occur or what the trigger is. It is known that high nitrogen and phosphorus levels and a high-water temperature are required for the bacteria to grow. But why 2017 and not 2018? No one really knows.
Last summer the Muskoka Watershed Council (MWC) which operates similarly to a conservation authority, informed the lake associations that it would like to start a project to collect data on lakes that have had toxic algae blooms. The algae working group was formed comprising Dr. Peter Sale (chair), Dr. Andrew Patterson - Dorset Lab, environmental scientists from several universities in Ontario, other members of the MWC and members of the lake associations involved. We learned that the algae blooms on the 4 lakes consisted of 4 different types of cyanobacteria which contributes to the complexity of studying and determining the cause of blooms. We were encouraged to find that there is an ongoing study in the New England states that has been found to be useful.
It was decided that we would collaborate with them and use their protocol to collect samples in hope of adding to the data and contributing to the understanding the logistics of an algae bloom. The lakes involved in our area are Three Mile Lake, Leonard Lake, Peninsula Lake and Clarke’s Pond in Lake Joseph. Every two weeks we collect samples at about the same time of day. We record air and water temp, wind direction and speed, measure the water clarity and make note of any significant weather incidents. Samples are taken near shore and offshore then labelled and frozen. They are then transported to the Dorset Environmental Science Centre for testing. It has been determined that blue/green algae fluoresce under certain light and the amount of fluorescence is proportional to the amount of b/g algae present. At Dorset, the samples are thawed, and a portion put into a fluorometer. The readings are recorded. Since these samples remain at Dorset, they will be available for further testing if necessary. At the end of this season the results and the protocol will be evaluated, and decisions will be made as to whether to continue the study, expand it or change it.
