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Food caching is a behavior exhibited by many animals, including several species of birds, that involves hiding and storing foods for later use. Notable food-caching birds include corvids (jays, nutcrackers, ravens), chickadees, nuthatches, woodpeckers, and even owls! For some species, such as Mountain and Black-capped Chickadees, caching food in the late summer and fall is necessary for survival during winter months. These species rely on excellent spatial and episodic memory, which is reflected by large hippocampi and the ability to cache and retrieve thousands of food items during the year. Black-capped Chickadees actually increase the size of their hippocampi during parts of the year to enhance their caching superpowers! Many food-caching birds remember other birds’ caches on top of their own, and because of this, food-storers must be careful that others do not know where their caches are in order to prevent them from being stolen. In several studies with scrub jays, it was observed that the birds would hide their food as far away as they could from observers, and used barriers that blocked other birds’ view when possible. Additionally, it was found that birds were able to track the different rates at which different foods perished, and used this knowledge to decide which caches to recover first. Some species, like the Chestnut-backed Chickadee cache for shorter periods of time, and often save a snack for later in the day or the next morning. However, birds’ memories are not perfect, and this forgetfulness provides for a key ecological function – seed dispersal and forest propagation. Clark’s Nutcrackers cache tens of thousands of seeds each season, and those that are forgotten become the next generation of pine trees. For trees such as the whitebark pine, the birds’ forgetfulness is a necessary driver of their reproduction. Learn more about Clark’s Nutcrackers’ role in forests here!
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