Black Ops Squirrels

December 26, 2015

Written by Thom Parrish

Reported sightings from visitors of small shadowy black furred creatures inhabiting the woods surrounding Effie Yeaw have increased during the month of December. Recently a woman came into the Nature Center and recounted that she and her grandson had witnessed a small black skunk quickly scurrying up and down tree trunks and leaping across branches! Earlier this month a young man came in from the preserve and timidly asked if such a thing as a black squirrel exists; unsure whether his eyes were playing tricks on him or if he had just discovered a new animal. When I ask the witnesses where they see the creature their answer consistently indicates the same location; the woods to the left of the stairs on the bluff trail.

I was curious to see the creature myself, so together with my camera I made my way down the bluff trail to quietly wait. It was late afternoon and I was alone on the trail. Minutes passed before I lost track of time and I soon found myself entertained watching some nearby deer graze. I had almost forgotten my reason for being there when something small and dark moved quickly off to my left. I turned my head toward the movement and to my surprise there, clambering over fallen oak limbs not ten feet away, was a black squirrel.

In the riparian woodland of the American Parkway there are three species of squirrel that can commonly be encountered. The California ground squirrel Spermophilus beecheyi, is perhaps the most commonly viewed mammal in the Sacramento region. Then there are the tree squirrels; the native western gray squirrel, Sciurus greseus and the introduced eastern fox squirrel, Sciurus niger.

Although not unheard of, black squirrels are somewhat of a rare sight in the American Parkway. Squirrels primarily are gray or brown, however there are some exceptions. For example, the Eurasian red squirrel is….....well, it's red. In certain regions of the American Mid-West you can find entire populations of squirrels with snow-white fur; a leucistic sub-group of eastern gray squirrels.

There is also the giant squirrel of India (pictured here) which can reach lengths of 3 feet; this squirrel has a two-toned coat of beige and purple! (I wish I took this picture, but no, I didn’t go to India.)

So what are the black squirrels? The black squirrels at Effie Yeaw are simply a melanistic variety of the eastern fox squirrel. Like a black panther…, but a squirrel. In the North Eastern states as well as Eastern Canada, there are entire populations of squirrels where black is the predominant fur color! These squirrels seem to enjoy an advantage by having darker fur in these regions. Their black fur can provide better concealment from predators in the shade of the thickly canopied forests. Their dark fur also helps them absorb more radiant warmth from the sun. In addition to black fox squirrels, the eastern gray squirrel is also known to have a melanistic sub-group. The western gray squirrel however, is not known to manifest in a melanistic variety. While having black fur would undoubtedly provide better cover during the dark of night, both fox and gray squirrels are diurnal, black fur not withstanding. The northern flying squirrel, found in the Sierra’s, is the only nocturnal North American squirrel.

Eastern fox squirrels are the largest of the North American tree squirrels. Typically a fox squirrel has a peppered gray-brown back with a brownish-orange underside.

One of the Effie Yeaw Fox Squirrels

There are several recorded incidents in the early years of the 20th century when eastern fox squirrels were released into parks and college campuses in the state of California. The fox squirrel has since thrived in the state to the point where they often outnumber native squirrel populations. One reason for the fox squirrel’s success in California is that fox squirrels have two litters of kits in a year; one in the winter and then a second in late spring. The native western gray has only one litter a year in mid-winter. Fox squirrels tend to spend more time foraging on the ground than other tree squirrels. Their diet consists mostly of acorns and various nuts and seeds. Fox squirrels are also known to be partial to berries and citrus fruits. When typical food sources are scarce, fox squirrels have even been observed eating insects and bird eggs. They also are not as social among themselves as gray and ground squirrels; they typically forage alone and don’t come together a whole lot outside of breeding seasons.

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Back on the bluff trail I stood still and continued to watch the black squirrel forage about on the forest floor. The squirrel found an acorn and began to assess the safety of its surroundings. The squirrel was aware of my proximity, and began to cast nervous glances in my direction. Squirrels are intelligent animals, they will actually pretend to bury a food item in different locations to throw off any would be thieves before actually burying it. They also are able to remember where they bury their food (most of the time anyway). Squirrels use spatial memory and a keen sense of smell to locate their stored food items. Squirrels are also known to bury food near landmarks that aid them in remembering where they stored the food.

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Maybe the squirrel didn’t want to take the chance that I would steal its acorn or perhaps the squirrel was just hungry, but rather than hiding the nut the squirrel felt content to sit upright on the ground and eat it there on the spot. The squirrel grasped the acorn with in its nimble finger like claws and nibbled away.

The squirrel finished the acorn in seconds and was already on the move looking for the next bite. In the trees high above, acorn woodpeckers were busy at work gathering and storing acorns of their own.

The squirrel climbed up an oak next to the woodpecker’s granary tree and hungrily eyed their food stores.