Starry Stonewort is an extremely aggressive, fastspreading macro alga. It has been spreading throughout the Trent-Severn Waterway for several years and is now in Ston(e)y Lake. From a few small patches identified in the summer of 2017 it is now in areas of Gilchrist Bay, The Lost Channel and in areas of the Big Duck Pond.

Starry Stonewort poses a significant concern to anglers because of its impacts to fish habitat and fish spawning areas. The spread of starry stonewort (SSW) may lead to a decline in fish, particularly bass that typically spawn in native chara. The dense mats formed by starry stonewort are very different from other invasives we have experienced. When starry stonewort takes hold, it causes a loss of aquatic plant diversity, shallow water habitat and fish shelter. It forms a “wall” pushing smaller fish offshore towards predators.

For more 2020 Actions on Starry Stonewort, click here. (pdf – 3MB)