Marine biologist Kyle Knysh explains that the discoloration and odor resembling rotten eggs in some waterways in P.E.I. are due to the presence of sea lettuce, a type of algae that thrives in high-nutrient conditions. As sea lettuce decomposes, it consumes oxygen from the water, leading to an anoxic event.
Several discolored waterways, including an estuary in the Oyster Bed area, have been reported to the province this year. The Department of Land and Environment noted that the green and grey-white water observed on July 9 indicated low dissolved oxygen levels in the estuary.
The province regularly monitors oxygen levels in various waterways and plans to analyze oxygen data trends from monitored estuaries over the past decade in collaboration with Fisheries and Oceans Canada.
Knysh advises caution for those suspecting an anoxic body of water, urging them to avoid contact as the water may have a foul odor similar to rotten eggs. While some wildlife have adapted to low oxygen conditions, many marine species struggle to survive in such environments, either needing to move away or facing the risk of perishing.
Concerned individuals can contact the Land and Environment Department to report issues with water quality on P.E.I.
