Why did the bear climb the tree?

Bear claw marks up a tulip tree. The other side of the tree had identical marks.

I took a walk down by the Musconetcong River yesterday (near Point Mountain). Two tall trees on a bluff over the river had bear claw marks all the way up the trunk. On both trees - a tulip poplar and a black walnut - there were two lines of claw marks, one on each side of the trunk. They were both about 15-20 inches in diameter. As I gazed up at the marks, which went up as high as I could see, I thought: why did it bother going all the way up there? I suppose bears may eat black walnuts, since I've seen their poop full of crushed hickory nuts (see previous post). But the tracks were recent, and walnuts have already fallen off. And tulip tree seeds have almost no meat on them. We were way off trail, so maybe a hunter or a gunshot scared it up there - gun season just started recently. Or maybe it just wanted to have a look around.

Close up of the claw marks on the tulip tree.

Point Mountain, Hunterdon County, NJ.