A strange brown tint showing up in parts of Casco Bay has some Maine lobstermen and clammers worried.
The Maine Department of Marine Resources is keeping an eye on a phytoplankton bloom called Karenia mikimotoi, which has been spotted from Portland Harbor down toward Harpswell. It’s been about nine years since this particular phytoplankton has appeared in Casco Bay.
The good news is that it’s not considered dangerous to people, and seafood that’s alive and properly harvested is still safe to eat. The concern is what it can do to marine life.
The bloom can make the water look noticeably brown, and it can reduce oxygen levels in the water. That’s a problem for fish and shellfish, especially in places where the bloom becomes more concentrated.
Some lobstermen in Portland Harbor have reportedly lost lobsters being kept in wet storage crates overnight. In one case, several lobsters died in a single crate.
WGME explained in part, farther up the coast, clammers in areas like Maquoit Bay and Middle Bay say they’re seeing a big drop in their daily harvests. Some who would normally dig four or five bushels of littleneck clams are now getting only one or two.
State officials say current concentrations are still much lower than what Maine saw during a larger bloom in 2017, but fishermen and shellfish growers are hoping it doesn’t continue to spread.
Similar blooms have also been reported along the New Hampshire and Massachusetts coast.
For now, it’s more of a concern for Maine’s marine industry than for seafood lovers.
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