The Black Walnut is common in Eliza Howell Park and is very popular with squirrels, especially the Red Squirrel. In the fall, I love to watch these little “critters” as they energetically harvest the nuts from the trees (See “The Red Squirrel: A Different Walnut Hoarder,” September 25, 2018).
In the winter, I find clear indications that the hoarded walnuts are being consumed.
Anyone who has attempted to crack open the hard-shelled black walnut to get the nutmeat knows how difficult it is to crack these shells open at all and how difficult it is to do so without shattering sharp pieces all over. It is impressive to see how neatly these shells have been opened and emptied.
Every nut is opened in almost exactly the same way. In this close-up, the marks left by the cutting teeth are clear.
What might not be evident from the picture is that the squirrel opens each nut twice, once on each side. The next picture of the same nut, side 1 and side 2, is more evidence of how systematically the opening method is used.
Not all squirrels open walnuts in the same way. A few of the open shells I have found look very different, opened by a different species.
Here is an example.
Though I have not had the opportunity yet to watch it in the act of cutting open a walnut, I am quite sure that it is the Red Squirrel, not a Fox Squirrel or a Gray Squirrel, that uses the method of opening the nuts from both sides.
The two-sided open shells are usually found together in a cluster and Red Squirrels hoard their nuts in a larder while Gray and Fox Squirrels scatter hoard. Further, these shells are found in the very same park locations where I often see Red Squirrels; the two locations I found clusters so far this winter are the two locations I checked because of earlier sightings of the animal.
The Red Squirrel (photo by Margaret Weber):
The Red Squirrel is the smallest and least common of the tree squirrels in Eliza Howell Park, but, to me, its behavior is the most fascinating.