Wild Ideas: When food is plentiful, animals often cache in

Recently, while trying out the beer on tap at Rappahannockâ??s new nano brew pub at Hopkinsâ?? Ordinary in Sperryville (excellent!), I ran into a former landlord who lives in Gid Brown Hollow. He reported seeing a red fox catching and burying prey in a field near his house.

The fox in question was using a typical hunting strategy for the species â?? killing its prey (likely a mouse or other small rodent) by pouncing on it, then digging a shallow hole and burying it by pushing dirt and debris over it to camouflage it. My landlord said he hadnâ??t seen this behavior in foxes before . . . and neither had I, although I did know that other canids, such as wolves and domestic dogs, bury or otherwise hide food.

In doing some research, I found some foxes will even stash food in low tree cavities, or under buildings. A YouTube Video shows a male fox caching a chicken wing (apparently supplied by humans) in a corner of his den, which was under a shed, only to have his mate and cubs find and consume it. According to several sources, foxes will cache food when theyâ??re full, when the food is low on their list of preferences and more desirable food is available, or when under stress from predators (including other foxes) who might be in competition for the food nearby.

While my observations of wild canids have mostly been brief and serendipitous, Iâ??ve had a lot of opportunities to observe dogs, and caching behavior is common with Canus familiarus. Iâ??ve found their caching behavior often extended to my favorite belt and shoes, and whatever else I least want them to bury.

My motherâ??s terrier-Chihuahua mix, Silkey, who was rarely off the lead, used to stash her toys and treats in the nest of wires behind my computer when she lived with me. Sheâ??d place her prize carefully in the tangle, then use her nose to try to push the wires over the item for camouflage. I tried to discourage her before she or my computer got fried, but I inevitably would find a new treasure any time I had to do anything back there.

Similar to a lot of other predators, foxes are to a great extent opportunistic hunters, killing when the opportunity presents itself, even after a full meal. This does not make them wanton killers. They waste not, for, in their lives, want is just around the corner. They are basically omnivorous, eating small animals and rounding out their diet with fruit. They are also keen scavengers.

Canids are not the only animals that cache food. Humans are arguably the most ardent cachers â?? of food and other things, sometimes to a pathological extent. Such â??hoardersâ? have lately become the subject of â??realityâ? TV shows. I think some people watch these shows because they recognize they might be just one stack of newspapers away from starring in them.

Some animals have special physical adaptations that help them to cache food more easily. Chipmunks, for example, have large pouches in their cheeks that accommodate an amazing amount of food, so they can scoop up a large amount quickly and head for cover before they are discovered by a predator. I remember as a kid regularly watching two eastern chipmunks (Tamias striatus) plundering the dish of bird feed my parents put out on our patio when we lived in what was then the town of Fairfax. The dish was down on the bricks near the edge of the patio.

One of the chipmunk pair would emerge from their hole in the side of a small hill at the edge of the yard, climb up, by way of an overhanging forsythia bush, the short wall that supported the patio, It would then run at breakneck speed along the top edge of the wall â?? tail sticking straight up like a battle flag â?? to the dish. There it would stuff its cheeks until its head looked doubled in size, then reverse course at the same speed. The chipmunks were a tag team, often almost literally running into their mate coming from the other direction. Each chipmunk would dump out the food in their den and head straight back. It didnâ??t take them long to empty the feeder. As with any real estate, their â??cachingâ? in came down to location, location, location.

According to the Adirondack Ecological Centerâ??s website, the eastern chipmunks in that area prefer beechnuts, and can stuff as many as 32 of the husked nuts into their cheek pouches at one time, â??which by the end of autumn may contain 5,000-6,000 nuts.â? (See hilarious photos and videos of chipmunks in the U.K. stuffing their pouches with food at tinyurl.com/onmxsps.)

To ensure someone else doesnâ??t steal their cache, most animals that store food this way regularly check on it. Many animals, including squirrels, chipmunks and foxes, tend to spread out their food in small caches (â??scatter hoardâ?) so that, although one may be discovered by another animal, enough will remain. When it comes to chipmunks, the Ecological Centerâ??s site says, â??small supplies, located throughout the home range, may later be eaten on the spot if perishable or consolidated in one of several large galleries in the burrow system or even in the underground nest.â? Scatter hoards may offer an alternative food supply if the chipmunkâ??s main food cache is stolen or destroyed and â??provide crucial nourishment during the winter, mid-summer and early spring and occasionally when seed and nut crops fail throughout the entire year.â?

Among Virginiaâ??s wildlife, squirrels are probably the best-known scatter-hoarders. So how do squirrels find the many acorns and nuts they bury? According to neuroscience researcher Pierre Lavenex, quoted on the University of California-Berkeley website, they remember the locations:

â??These squirrels are not putting any flag there, they are not smelling the nuts, they are really remembering the exact location of their nuts. They use information from the environment, such as the relative position of trees and buildings, and they triangulate, relying on the angles and distances between these distant landmarks and their caches.â?

© 2014 Pam Owen

Pam Owen is a Virginia Master Naturalist. She lives in one of the hollows of Rappahannock County. You can see her blog at Wild Ideas in the Blue Ridge. You may reach her at wildideas.va@gmail.com.