Over the years, Grover Krantz would sometimes climb into his car at night and go for long, lonely rides into the woods of the Pacific Northwest. Creeping along the back roads at 25 mph with a rifle and spotlight at his side, Krantz desperately hoped his elusive quarry, a sasquatch, would show itself.

But it never did. Not once in more than 30 years of looking.

Krantz, considered one of the world’s foremost authorities on the supposed apelike denizen of the Northwest’s forests, died Feb. 14 of pancreatic cancer in Port Angeles, Wash. He was 70.

Krantz was unique because of his credentials. A longtime physical anthropologist at Washington State University in Pullman, Wash., he approached Bigfoot as a scientific problem that needed to be solved even if it meant gunning one down.

What perplexed and even maddened colleagues but delighted Bigfoot enthusiasts was that Krantz was a legitimate academic. He was a respected lecturer and expert on human evolution, with dozens of peer-reviewed papers to his credit, as well as a book titled “Big Footprints: A Scientific Inquiry into the Reality of Sasquatch.”

“I think the more criticism he got on (Bigfoot), the harder he dug in his heels,” said Don Tyler, a former student of Krantz’s and the head of the anthropology department at the University of Idaho. “He thought he was approaching this thing in the correct way, as a scientific problem. But many professors considered it a topic that was not appropriate to be studied.”

Although Krantz had heard the story of Bigfoot as a teen, he remained skeptical until he was called in 1970 to look at alleged Bigfoot tracks in northeast Washington. Expecting to find an obvious hoax, Krantz thought the footprints were too sophisticated to be fake because one of the feet showed a crippling bone injury.

As the years passed, Krantz interviewed hundreds of people who said they encountered Bigfoots in the region. He also did a frame-by-frame analysis of the famous short film made of an alleged Bigfoot by Roger Patterson in 1967 near Willow Creek in Northern California.

Krantz thought the images were legitimate. Others thought it an uninspired stunt featuring a man in a monkey suit.

Using casts of footprints, films, witness encounters and his knowledge of human evolution, Krantz developed an elaborate natural history of the sasquatch.

Asked by a magazine writer why sasquatch remains had never been found, Krantz replied: “Well, that’s the annoying part. Although we found jaws and teeth in China from what I guess to be sasquatch’s ancestor, we have nothing in North America. But this is probably because, first, it’s a rare animal, and second, it has no natural predators, so they die slowly and creep off and hide. Bears do this. Practically the only bear specimens we have in museums had to be shot by somebody.”