Massachusetts authorities sent out an advisory about possible collision with a large number whales that have been sighted in Cape Cod Bay.
The North Atlantic right whales were spotted feeding by the Center for Coastal Studies in the lower and eastern Cape Cod Bay on January 18.
The center documented at least 27 whales.
The Massachusetts Division of Marine Fisheries is urging mariners to travel with extreme caution around Cape Cod Bay as large concentrations are expected.
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"For the safety of both mariners and whales, vessel operators in this area are strongly urged to proceed with caution, reduce speed (less than 10 knots), and post lookouts to avoid colliding with these highly endangered whales." said the authorities in a press release.
Any boat is prohibited from approaching the whales within 500 yards by state and federal law. The Massachusetts Environmental Police and U.S. Coast Guard are authorized to enforce this law.