I get that question a lot. How can they hide from us, why can't anyone snap a good picture of one of these things?
Simple. The U.S. has over 700 million acres of forest, and that's not including Canada, which exceeds the U.S.
Basically, it's a game of hide and seek, "hardcore" edition.
It's not like trying to find a needle in a haystack, it's like trying to find a piece of dust in a desert.
Oh, and regarding the Sierra Kills. Yeah, Ghosttheory sums it up pretty well.
Here's the problem. Ketchum doesn't have the best record. She's not a hoaxer, but she shouldn't have released a press release, she should have waited for it to get published In a reputable scientific journal. It wasn't necessarily her fault though, as Igor Burtsev accidentally spilled the beans the day before and was sorta forced to.
Anyway, according to a few sources, the BIG release is supposed to happen by years end.
AND, if all else fails, we have the Oxford DNA study, which is one of the most credible colleges in the world.