"Fieldnotes," December 29th & 30th, 2013: "Clark's Nutcracker," by Charles Miller / Caroline Kurtz.
http://www.montananaturalist.org/
"Clark's Nutcrackers are birds of the montane forest and breed early at high elevations while the snow is still on the ground. To feed their young, the parent birds can recover cached seeds in as much as eight inches of snow. It appears that the nutcrackers have very few senior moments; they have excellent long-term memory. Researchers have noted that Clark's nutcrackers are able to recall the precise locations of about 2,000 caches for up to eight or nine months."