See it: Large great white shark spotted off Cape Cod in season's first reported sighting

CAPE COD, Mass. – Whale watchers were in for quite the surprise Saturday as they watched a great white shark devouring its next meal just feet from their boat.

Michelle Silva with the Dolphin Fleet Whale Watch said their tour group watched as the estimated 12-foot shark feasted on a juvenile gray seal on Stellwagen Bank National Marine Sanctuary. The federally protected marine sanctuary is located east of Boston, Massachusetts, between Cape Ann and Cape Cod.

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"The entire event only lasted around 7 minutes from when we first saw the shark quickly break the surface of the water, in what we think was the initial strike, to when the seal was consumed," the whale-watching group said on Facebook.

"We’ve shared the video with shark researchers who have confirmed this is the first eyewitness confirmation of a white shark and predation this season," they added.

Officials warn that sharks are back in the area, and it is a great reminder to be shark smart when venturing out into open waters.

STAY SHARK SMART: WHAT TO KNOW WHEN YOU HEAD INTO THE WATER

The Atlantic White Shark Conservancy shares these helpful tips when visiting Cape Cod:

• Stay close to shore where you can hear any warnings if they go out
• Swim in groups. Don't go out alone
• Avoid marine life. Seals and fish that can be food for sharks
• Avoid dark, murky water you can't see through
• Always pay attention to flags or signs
• A purple flag means sharks frequent that area
• Don't splash around

And most importantly, the nature conservancy says to listen to the lifeguards if they warn you to get out of the water. Lifeguards get these alerts firsthand from researchers and are in charge of deciding if and what action to take if there could be a shark nearby.