Deadly Casco Bay algae bloom dissipating, impacts still being assessed

An algae bloom that wiped out shellfish in parts of Casco Bay is dissipating, though officials say the full impact on harvesting is still being assessed. Town officials and scientists have been monitoring a phytoplankton bloom of Karenia mikimotoi since it was reported in early September. The nonprofit Friends of Casco Bay reported an Oct. 9 update showing declining cell counts in inner Casco Bay, while some areas continue to suffer effects from low dissolved oxygen that can suffocate shellfish. The Maine Department of Marine Resources closed shellfish harvesting in Maquoit Bay in Brunswick and the eastern side of Middle Bay in Harpswell, then reopened Maquoit Bay on Oct. 8 as water clarity improved. The department is asking industry workers to report low-oxygen signs, discoloration, and odors, and will post further updates online.