Upper Stoney Lake Benthic Assessment


Upper Stoney Lake Benthic Assessment


Emily Banks, Troy Deziel, Oliver Kurz, Jean Leishman, Nadia Pagliaro, Nate Stephen

Host Organization

Upper Stoney Lake Association, Ed Paleczny

Supervising Faculty

David Webster

Reference Number



April 2023

Location of Document



Haliburton County, Stoney Lake


Benthic biomonitoring


Stoney Lake is in Peterborough County, approximately 30 km northeast of the City of Peterborough. The majority of residences situated along the lake are summer cottages, with many properties having docks and recreational motorboats. The lake straddles the border of the Canadian Shield and the St. Lawrence Lowlands physiographic regions.
Since 2020, U-Links has partnered with Upper Stoney Lake Association (USLA), Trent University, and Fleming College to monitor and report on the lake’s benthic macroinvertebrate populations. This study is currently in year three of a proposed total of five years, after which a baseline knowledge will be reached regarding the lake’s macroinvertebrate species richness and diversity. Research spanning five years is considered long-term, and the data in such studies has a high level of validity. Macroinvertebrates serve as excellent bioindicators of overall littoral ecosystem health. With five years' worth of macroinvertebrate data, trends may be recognized and recommendations for the future can be made.
Several areas of concern make Stoney Lake a good candidate for continued research. According to E. Paleczny (personal communication, December 5, 2022), the stressors to aquatic ecosystem integrity of Stoney Lake include climate change, invasive species (e.g., Nitellopsis obtusa (starry stonewort (SSW))), decline in water quality (e.g., nutrient input, blue-green algal blooms, chemical contaminants), water level fluctuation, and development pressures (e.g., marina's, golf courses, proposed condo and tiny home developments, shoreline development, watershed scale impacts from forestry, mining and agriculture). E. Paleczny (personal communication, December 5, 2022) further stated that the synergistic effects of these stressors are resulting in rapid decline in healthy populations of aquatic species (e.g., walleye), increases in the number of species at risk (e.g., wood turtle), and increased eutrophication leading to increased occurrence and abundance of algal blooms. There are also many unseen effects including increased toxic effects on aquatic life.
Excess algae growth may be fueled by phosphorus and nutrient runoff from the golf course and cottage lawns. If algae growth increases dramatically, lake eutrophication may occur, which would have detrimental effects on animal populations. Algae blooms increase the biochemical oxygen demand (BOD) level by encouraging the growth of specific bacteria (Encyclopedia.com, 2019). A greater BOD rapidly reduces oxygen levels, which can cause fish and other aquatic animals to lose their oxygen supply.
In 2022, there were no observable impacts or changes in macroinvertebrate species presence at a lake scale, however, this study does not address localized impacts from stressors or other shifts or changes in aquatic ecosystem function. It also does not address any changes to baseline conditions prior to 2020. Increasing sampling sites where there are concerns about localized stressors such as development impacts would help to assess if there are localized impacts to macroinvertebrate populations.


Trent University



Emily Banks, Troy Deziel, Oliver Kurz, Jean Leishman, Nadia Pagliaro, Nate Stephen 2023, Upper Stoney Lake Benthic Assessment, Trent University