Hoarding is an animal behavior of gathering and storing food in a location hidden from similar or related species. The name hoarding is mostly used for rodents, whereas caching typically refers to birds. Nevertheless, the behavior is similar in both species. Animals gather food during surplus for use in times of deficiency. Evidence also suggests that hoarding is also done to ripen food. Hoarded food may feed the animal on a long-term basis or for a few weeks or days. Common animals that hoard food are squirrels, hamsters, woodpeckers, and rooks. The western scrub jay is also skilled at hoarding. Animals specialize in different types of caching. In scatter hoarding, animals separate caches depending on specific foods and store them in unique places. In contrast, ladder hoarding animals create a few large caches without separating individual food items.
Functions Of Hoarding
Caching is typically a method to store excess food for later consumption. Although this behavior is common in rodents and birds, large animals such as lions, leopards, and jaguars hide prey in trees or bushes to be consumed later. In some animals, caching is a seasonal behavior where food is gathered during summer and autumn for consumption in winter when food is scarce. The tayra weasel of Central America gathers and hide green plantains then returns to eat after they have ripened. Leaf-cutter ants store inedible leaves in underground chambers to be ripened by fungus.
Animal That Hoard Food
Tree squirrels can be seen running around during autumn, gathering food for the impending winter season. They feed on acorns from more than 20 species of oak along with walnuts, hickory nuts, hazelnuts, and beech nuts. They are scatter hoarders and ensure food safety by spreading their caches across several hiding places. When a tree squirrel finds an acorn, it checks the nut for signs of weevils. Those infected are consumed on the spot, including the weevils, since they won’t last long while the rest is stored for later use. Squirrels bury nuts further from the tree to reduce the odds of being found by other animals. Thievery is common among tree squirrels. In addition to multiple stashes, they dig several fake holes to deceive other animals or rebury the same stash multiple times. One squirrel can create up to 1,000 caches in a year. Thanks to their extraordinary sense of smell and detailed memory, they recover about 80% of the food. Some squirrels use a strategic pattern to organize their caches to increase the accuracy of retrieval. Besides seeds and nuts, the American red squirrel harvest mushrooms.
The yellow pine chipmunk collects about 60,000 items during summer and autumn for the upcoming winter and buries them in different caches. Ironically, the chipmunk drifts into a semi-hibernation, in which it emerges once a week to feed for the next four months. The North American eastern chipmunk prefers storing food in burrows that can stretch for more than 10 feet. Unlike its counterpart, it does not keep several stashes but gathers its food together. Though this reduces movement, there is a downside. About 50% of eastern Chipmunks lose their food to other animals. Groundhogs, mice, and hamsters also prefer to keep their food in a single stash.
Moles’ underground lifestyle offers protection from extreme weather, but they do not hibernate and can, therefore, go hungry if they do not stock up for the winter. Earthworms make up a substantial part of their diet, and they can eat an equivalent of their body weight on a single day. During winter, worms become harder to find as the soil chills and become hard. Moles have, therefore, developed the most bizarre hoarding strategy in the animal kingdom; they capture and keep earthworms alive as prisoners. They bite the head to inflict an injury that immobilizes the prey. Some have toxins to paralyze earthworms. As many as 400 live worms can be found in a single chamber.
Shrews resemble mice, but they are closely related to moles. They spend much of the time in burrows. Just like moles, they imprison live prey in burrows and feed on them during winter. Shrews do not fully hibernate but enter a state of torpor where they wake up periodically to feed. Venomous shrews use toxins to incapacitate their prey. They mostly feed on invertebrates such as snails, insects, and worms, but they may use toxins to incapacitate larger prey such as frogs, mice, and birds. The short-tailed shrew is a ferocious eater and needs an equivalent of its weight every day. A few hours without food could be fatal. During winter, the shrew requires 40% more food to maintain constant body temperature.
Most woodpeckers peck tree barks to find Insects and invertebrates, but a few members of the species use the skill to store food instead. The red-bellied woodpecker and the red-headed woodpecker are some of the most skilled hoarders in the bird kingdom. The acorn woodpecker of North America creates granaries in trees that can store as much as 50,000 nuts at a time. The birds’ success is attributed to their social lifestyle, where a family of about a dozen individuals cooperates on tasks such as foraging and maintaining caches. They wedge acorns and other nuts tightly that it is difficult for other birds and animals to steal. Members occasionally check granaries and move loose nuts.
Common ants collect leaves and store them underground for consumption during the winter. Honeypot ants have a peculiar way of hoarding food. Their colonies feature replete ants who are gorged with large amounts of food until their abdomen swell like water balloons. They are moved to a special chamber in the colony where they periodically manufacture honey for the other ants. Other species use stings to immobilize prey and carry it to their nest. Fire ants desiccate prey and stockpile them in the warmest and driest area of the colony.
Corvids are better known for their intelligence, like recognizing specific human faces and manufacturing tools. Their powerful memory also makes them prolific hoarders. Dick Clark’s nutcracker can hide about 30,000 pine seeds during spring and recover most of it in winter. Scrub jays stockpile more perishable foods like fruits and insects, which require them to identify precisely where each item was placed and the duration.