They captured pictures of a fin whale—the second largest animal in the world—off Minor Island Thursday on a whale tour.

It's a species of whale that hasn't been seen in the area in decades.

Janine Harlis is the photographer who captured it. She has taken countless pictures of whales while riding on the Puget Sound Express this summer alone, and at first she had no idea the photo she snapped Thursday was any different.

"No, I had no idea—thought it was a humpback at first,” she explained.

But the Center for Whale Research confirmed Janine captured history.

"The only sighting we've seen of a fin whale anywhere in this region was about thirteen years ago off Vancouver Island,” said Michael Harris with Puget Sound Express.

Michael says the massive and endangered fin whale which can grow as large as 90 feet and 80 tons was driven out of the Puget Sound—nearly wiped out by hunters—along with the humpback whale, which recently made a comeback.

"Humpbacks started coming back a couple years ago, led kind of by a big female called ‘Big Momma’ who started coming in and started bringing her calves, then males started coming in, and now we're seeing humpbacks almost every day,” Michael said of the reversal.

That’s exactly what they hope will happen here—that this juvenile fin whale, spotted again by another tour Friday, will bring with it friends and family, and stay.

"This is the first fin in, let's hope we get a bunch in,” Michael concluded.

Janine will be ready with her camera, but she's not sure any other picture will be as rewarding as the first.

"I don't know, this one's pretty cool,” she said of the inaugural picture.

To keep track of this whale, experts will go back to the same spot it was originally spotted, but there is always the chance it could move on.