DISTRIBUTION OF MICROCOLEUS AND ANATOXINS IN KJI-QOSPEM, SHUBENACADIE GRAND LAKE

Abstract

In the spring of 2021, two dogs died after ingesting suspected benthic cyanobacterial mats along the shoreline of Kji-Qospem lake, commonly known as Shubenacadie-Grand, a large oligotrophic lake, in Nova Scotia. Toxin producing Microcoleus spp. were identified as the cause, and initial studies indicated the mats originated from a highly impacted tributary. The central objective of this thesis was to assess how widely distributed Microcoleus is throughout the lake system using a variety of analysis. Results from a two-year sampling program revealed that toxin-producing Microcoleus was present at several locations throughout the lake, although distinct cyanobacterial mats were only observed within the stream and lakeshore area where the dog deaths occurred. These findings add to a growing body of evidence demonstrating the wide distribution of Microcoleus within Atlantic Canadian surface waters.