Roger J. Lederer

“Acorn Woodpeckers of the western United States and Mexico store acorns in “granary” trees and defend them aggressively. They wedge the acorns into holes in trees or wooden telephone poles so tightly that crows, squirrels, and rats can’t raid their supply. To remove an acorn, a woodpecker hammers it with its bill to crack the shell and extract the meat. Clark’s Nutcrackers, capable of carrying more than 90 pine seeds at a time in a pouch under their tongue, store many of them in caches, even under the snow. They cache two to three times what they need for the winter and eventually find half or more of their seed caches later. Not only do the birds recall the site of these caches for up to nine months, they also remember the relative number of seeds and the size of the seeds in each cache. Florida Scrub Jays cache food by burying one acorn at a time; if they observe another jay, a potential cache robber, watching them, they will return later to move the acorn. But they will only do this if they themselves were cache robbers in the past. Seems that honest jays trust the other ones and thieves do not.”
― Roger Lederer, Beaks, Bones and Bird Songs: How the Struggle for Survival Has Shaped Birds and Their Behavior