BOSTON (AP) — A record number of North Atlantic right whales have been spotted off Massachusetts, prompting state officials to warn boaters to stay clear of the endangered animals.

An aerial survey of Cape Cod Bay and surrounding waters on Tuesday identified 101 individual right whales, the most ever spotted in a single day.

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WBZ-TV’s Diana Perez reports

The previous high came last April when 70 of the whales were spotted during a single aerial survey.

Experts say the whales gather each year off Cape Cod to feed off tiny marine creatures called zooplankton.

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The Massachusetts Division of Marine Fisheries issued a high risk advisory to boaters due to the large numbers of whales and their proximity to shore.

Boaters are urged to reduce speeds and keep a lookout to avoid collisions.

Adult right whales average 45-55 feet in length and can weigh up to 70 tons.

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