Squirrels

May 31st, 2012 1:45PM-2:30 PM

The day is not cold but not warm either. Full cloud cover gives makes the day the ordinary Pacific Northwest weather, but luckily there is no precipitation. Almost no wind. The squirrels group are taking the class on a tour with activities in and outdoor, ranging from Mary Gates hall to Grieg Garden.

From the first day I arrived on University of Washington campus, I knew that squirrels were going to be a big part of my college life. Now that might be an exaggeration, but it is true that I was enlightened to see so many of them having to come from a city where I am not so sure most people have seen a wild squirrel. In fact, there are so many squirrels that I think if time comes to switch the UW mascot from huskies, we might as well become the UW gray squirrels.

The primary aspect of any squirrel that fascinates me is their capability to climb vertical slope of a tree bark. The agility of squirrels are incredible, especially the speed at which they climb up a tree. Their sharp claws seem to be helping them with the process, but if their claws are so sharp 1) how come there are no claw marks left on the bark of the trees? and 2) are their claws not damaged by walking on pavements and other artificial surfaces? The squirrels group have pointed out that squirrels might have a hard time climbing smooth barks. This is an interesting point; all the trees that I have seen squirrels climb have rough barks such as giant sequoia and pine trees - I have yet to see one climb up a birch. Discovering whether squirrels are capable of climbing up smooth bark trees may ultimately come down to play a part in habitat conservation measurements.

From their appearance, squirrels are adorable species. One of my friend mentioned that they shouldn't be as cute because squirrels dig into a garbage can for food. My friend's point - leaving aside the subjective argument of whether species that dive themselves into a garbage can is cute or not - reveals the trait that these squirrels are quite smart and can flexibly adapt to their surrounding environments. However, their intelligence does not stop there because eastern gray squirrels are capable of storing their food. In other words, eastern gray squirrels are capable of performing both spatial and temporal analysis to base their foraging behaviors. It certainly takes skill to develop a temporal mindset; animals like sheep I do not believe are capable of such abilities to store food. I have been wondering why I see squirrels during winter for a long time, but it is the storage of food allows the eastern gray squirrels to overwinter without hibernating.

Eastern gray squirrels are known to store their food in a tiny hole that they dig, which inevitably means that they have some source of guidance that allows them to remember the location of the holes. It seems like the mainstream hypothesis is that squirrels rely on scent of pheromone, but it could be pure memory. What is incredible is that squirrels dig several small holes to minimize the risk of the hole being dug up and precious food source stolen. Some squirrels have even been observed to fake digging a hole especially when they sense other squirrels watching them. This means, that in addition to spatial and temporal thinking, eastern gray squirrels could calculate risks as well. By using a huge tract of land as their territory, they manage to avoid the catastrophic situation of what happens to humans when houses get broken into.
I wonder if squirrels would fake digging a hole if species other than squirrels, like myself, observed them long enough. We could translate this situation into ours, of which situation we could imagine an animal staring into our house, directly at a refrigerator. If it is a duck or sheep peeking, then I would not bother whereas if it is a bear or a monkey, I would be concerned that bears and monkeys would be too strong or too smart to do anything about it if they truly decide to take food from a refrigerator. So my hypothesis rests upon that squirrel's decision to fake a hole depends on what species are staring at them.

Finally, it seems to be that the eastern gray squirrels are the only squirrels found on campus, and to me they look like a typical squirrel that pops up in children's picture book. It is a shame that eastern grays are driving the western counterparts to limited habitat. Since the eastern grays are the only species of squirrels that I know, whatever behavior of them becomes the behavior of all squirrel species in my mind. Because I know that is not true, watching the western grays might strike as a revelation.

Species List

Sciurus carolinensis - Eastern gray squirrel
Sciurus griseus - Western gray squirrel
Sequoiadendron giganteum - Giant sequioa

Posted on June 5, 2012 10:57 AM by bluehoneysugar