Several people have emailed to ask how it is possible for nutcrackers to access their seed stores during the winter's deep snowpack.
In fact, they use a variety of strategies. Clark’s nutcrackers regularly cache in exposed areas, such as steep cliffs and south facing slopes, where wind and sun prevent heavy snow accumulation. In one population in the Cascades, Teresa Lorenz found that the birds she studied cached up to 59% of seeds above ground. (The above ground caches were typically in needle clumps, in lichen or behind bark.) I didn't see nearly as much above ground caching, but I did see some. The birds tended to follow the snowline in the spring - I've watched them retrieving caches in recently melted open areas around the bases of trees, and right at the edge of melting snowpack, as the snowline recedes up a mountain. The birds also did retrieve caches from under the snow and ice. I have seen a Clark’s nutcracker dig diagonally down through about two feet of snow - its body was completely buried - then return to the surface with whitebark pine seeds (easily recognizable by the size). Harry Hutchins saw an individual peck through eight inches of ice to pull out seeds. Also, the birds are corvids, and like all corvids they are super opportunistic, and will eat other foods besides seeds when available. In the winter, this includes dead animals (such as roadkill or wolf kill), rodents, and insects hidden under tree bark. They especially love the suet I hang up to bait my traps.