NPS
Clark's Nutcracker in a juniper tree
Behavior:
Clark's Nutcrackers are part of a crucial symbiotic relationship with pine nut- producing species of pine trees including Pinyon, Limber, and Whitebark pines. The trees offer pine nuts as high-energy food to the birds and the birds cache the nuts in the ground. Any nuts that aren't eaten have a good chance of sprouting new pines. Without the trees, the birds would starve, and without the birds, the trees could no longer reproduce.
This sophisticated evolutionary relationship has its own built-in safeguards. First of all, the cones are so thick and tough that rodents seldom attempt to chew into them, but Nutcrackers with their crowbar-like bills can easily pry the nuts from the ripe cones. Even though a single Nutcracker will cache between 20,000 and 30,000 nuts each year, unlike squirrels they don't put all of their "eggs in one basket." Instead of a few large caches, Nutcrackers make up to 1,000 little ones. Some caches may contain as few as 4-5 nuts while others may contain 30-50. It is speculated that the reason few caches ever contain more than 50, is because bears can smell out the location of a large cache. Lots of smaller caches not only make it harder for the bird to lose its supply to theft, it also benefits the trees because it increases the chances that nuts will be placed in a good growing location.
The astounding thing is that even though the birds' brains are smaller than the nuts they cache, they remember with precision where up to 75% of their caches were placed. Other researchers theorize that their memory and mental mapping ability is much higher and that the other 25% is intentionally not used. Like good boy scouts, they are going the extra mile to be prepared. Perhaps it is no coincidence that the 30,000 nuts they cache represent about 25% more food than a single bird needs to survive the average winter. Caching an extra 25% might not be compensating for memory loss, but instead, actually a "planning for worst-case scenario" adaptation-- just in case the next winter is 25% longer and colder than the average.
Little is known about Clark's Nutcrackers' reproductive behavior as they are very secretive during the mating and nesting season which occurs in late winter--March or April--depending on elevation and latitude.