He's as elusive as the mist on a mountain lake, his hair as thick as the tangled underbrush of the deep woods. Most likely, if he's ever seen (again?), he'll be shot. And that may be the only way to conclusively prove he exists.For decades, Sasquatch --- also known as Bigfoot --- has defied scientific proof but has left tantalizing hints to lead many to believe in his existence.A notorious creature of impressive stature, he's also brought notoriety to those who studied him and claim to have spotted him.The late Grover Krantz, who was an associate professor of anthropology at Washington State University, once estimated there are about 2,000 Sasquatches living in the Pacific Northwest. In his 1993 book, "Big Footprints: A Scientific Inquiry into the Reality of Sasquatch," he describes the beast as nocturnal, most likely omnivores with an adult male standing 7 feet, 8 inches and weighing about 800 pounds.So how come hikers, loggers or hunters don't encounter them more often?Sasquatches are "probably the most intelligent animal in North America outside of man," Krantz wrote. He said the only practical way to prove Sasquatch's existence is to shoot one. Krantz said the most tangible evidence of Sasquatch is footprints, which may be preserved in photographs or plaster casts.Such was the case in 1998 for Randy Trusty and David Hart, both of Longview.While hunting in the woods above Little Cape Horn in Wahkiakum County, they discovered footprints unlike any they'd ever seen before. They made plaster casts of the prints and gathered a lock of extra-coarse brown hair"I've spent countless hours in the woods," Trusty said in a Daily News article in 1998. "To look down on the trail and see something that clear on the ground chills you to the bone. ... This evidence is enough for me that this creature exists."But for every small shred of proof, there are 100 hoaxes.