They are the largest whales in the world and two of them were spotted miles off the Cape Cod coast.

Every winter, researchers from New England Aquarium survey the Northeast Canyons and Seamounts National Marine Monument. This national marine monument is the first such monument in the U.S. and sits about 130 miles southeast of Cape Cod.

And it is full of amazing sea life.

In fact on the most recent survey flight by the aquarium two blue whales along with fin, humpback, pilot, sei, Sowerby's beaked and sperm whales were spotted, not to mention the dolphins.

It sounds like an awesome way to spend the day to me – fly over this bio-diverse hotspot in the Northeast Atlantic and see how many amazing sea creatures you can find.

And boy, did the researchers find some amazing sea creatures.

In a press release from the New England Aquarium, observers spotted sei whales for the first time ever. But it was seeing the massive blue whales that really made their day.

These rare and endangered whales are not only the largest whales in the ocean, but they are also the largest animals on the planets.

And two of them were swimming just over 100 miles from Cape Cod. Cool.

Probably no surprise that the blue whales were seen right over the Oceanographer Canyon, the monument's deepest canyon at 4,000 feet deep. You probably need a lot of space to swim when your about 80 feet long and weigh 300,000 pounds.

All in all, 322 whales and dolphins were spotted during the six hours of flyovers.

And researchers say every survey turns up something "different and exciting."

Who knows what they'll find next?