Urban Adaptations

 “The path that leads to knowing your wild neighbors is natural history” (15). Hanover  Street, Salisbury, Maryland. On a short one-way street, there are four houses, one apartment building, two-dozen cars, five oak trees, many house bushes, American robins, Grackles, crow species, vultures and a dozen or so eastern grey squirrels. This area is part of the Atlantic Coastal Plain, a flat, sandy area that is generally wet, with many rivers, swamps, and wetlands. This strip of street is no longer a wetland. It has been urbanized over the years to become what it is today. As a result, the lives of these eastern grey squirrels that live here is very different than that of those that lived here 200 years ago.

I decided to observe the grey squirrel as I noticed how they have been able to survive in many different environments. “After about two weeks of visits, life with the squirrels developed a routine” (16). The eastern grey squirrel (Sciurus carolinensis) is commonly found throughout North America, from southeastern Canada south to Florida and west to eastern Texas (4). Grey squirrels can also be found in some European countries where they are viewed as an invasive species. Grey squirrels are common in many different environments ranging from woodlands to farms to parks and backyards and even find a home on our university’s campus. Not only have squirrels been able to survive in many environments, they have thrived and are listed of least concern regarding their conservation status. Daily observation of grey squirrels interactions with human make clear that they have adapted well to the urban environment.

Watching the behavior of eastern grey squirrels is thought provoking. They exhibit many diverse behaviors and in engage in a variety of interactions with other flora and fauna in their every day life. This includes: interactions with other squirrels, interactions with other animals, interactions with humans (pets and cars) and interactions with the trees they inhabit.

Observation has led to the discovery of many facts about a grey squirrel’s life. Grey squirrels have to face a variety of challenges while living in an urban environment. Many of the obstacles faced day-to-day by urban grey squirrels are much different than those of a grey squirrel living in a wooded environment. Urban grey squirrels have to deal with different set of predators than their woodsy cousins. The urban squirrels are faced daily with humans, who continually invade their space and cause them to run away quickly. This can lead to a squirrel running onto a nearby road where even bigger problem must be faced: the automobile. Cars kill many squirrels everyday as they scramble across the road. Another problem faced by the urban squirrel is that of domesticated pets, such as cats and dogs. These urban predators cause squirrels to have to flee to the safety of trees and telephone poles.

But not all is treacherous here. Although humans have brought a lot of troubles to the grey squirrel, they have also provided them with many resources to survive and thrive. Development of urban and suburban areas has provided many means for survival to the increasingly urban grey squirrel. Even as natural habitats of squirrels have been destroyed, the urban landscape offers a new way for the squirrels to live. The grey squirrel has taken advantage of what humans have to offer. The trees out front along our street are not there naturally. I imagine that they were planted to beautify the new neighborhood as it was being built. But the squirrels saw the matter differently, relying on these tall oaks for food, safety, and shelter. Squirrels also trust that they can use a house attic, telephone poles, parked cars, and fence lines to their advantage. The urban grey squirrel will use any combination of these to escape humans, pets, and other animals and squirrels throughout the day. Observed interactions with grey squirrels and pets such as dogs as led to many interesting details. When faced with a dog, grey squirrels will quickly scatter to nearby shelter. Shelter can come in many forms, as squirrels are quick and can climb very easily. While a natural grey squirrel may run up a nearby tree, the urban squirrel has a few more options. Urban grey squirrels can climb up a nearby tree, as in the wild, or they can climb a proximate telephone pole, a house gutter, and even hide under cars. Grey squirrels in the urban setting can evade predators such as dogs by fleeing to structures not found in the wild.

As a grey squirrel flees from urban predators, they communicate with others in the area to alert them of a threat.  They make noises that could be described as kuks and muks, quaas and moans. These noises let the others know about the threat that is near. The noises may also be an alert to the predator. Communications also include postures.

Grey squirrels will also interact with each other. They run around chasing each other as they play and try to steal each other’s foods. As an interaction between grey squirrels, they will try to hide food from each other (9). A squirrel will know when another is watching and try to deceive others by hiding where they bury food (7). A grey squirrel will have an acorn and proceed to dig a few holes before burying their food in only one of these holes. This complicates other grey squirrels attempts to steal food hidden for later dates.

Grey squirrels are constantly burying caches of food. They will bury food for later in the day or for a longer time down the road. Based on observations, squirrels know what acorns will expire before others. They will return to some acorns sooner than others (6). Grey squirrels will bury many caches of food throughout their lives. Many of these caches can be forgotten about. These forgotten about caches of food, especially when a seed, develop into trees. Squirrels also have a diet that consists of many trees (buds, barks and blossoms), grapes, grasses, insects, birds (babies and eggs), and amphibians (8).

Eastern grey squirrels will live in trees, usually in a nest of leaves or in tree cavities. In the urban environment, squirrels will often live in attics of houses. The grey squirrel nest, called a drey, is made from sticks and leaves, and is usually in the fork of a tree. Grey squirrels will also use holes in trees made by other animals or natural cavities.

The grey squirrel uses trees for many purposes. Grey squirrels will use trees as shelter and food. They also use trees to escape from predators. As food, trees provide much nourishment for the grey squirrel. Grey squirrels consume many species of tree including oak, holly, beechnuts, maple, and poplar to name a few. The grey squirrel uses trees as its home as talked about earlier.

The behavior of squirrels is waggish. I enjoy watching them as they bounce around accomplishing their daily routines. As I have observed them, I have noticed that they are also observing me. They cautiously watch me as I walk around the block, studying every move that I make. They survey to make sure that I do not approach to closely to them. They witness my behavior to make their next move. They know their surrounding and identify the closest zone of safety. The observations these squirrels construct on me have lead me to believe that they are very clever creatures. They recognize all that I do and can figure how much of a threat I actually am to them.

I do not imagine that we know that much about squirrels. They are portrayed as curious little critters, constantly stuffing their faces with acorns, dumb rodents that do not know how to cross the street, hyper friends in Disney movies, and backyard pests that need to be removed. They are, in fact, smart animals that know how to adapt and survive in many different environments. They know how to interact with humans and pets, they know where to find food, and they know how to find safety and shelter quickly in times of need. The urban squirrel is a very smart animal that realizes a lot about its surroundings and how to survive. The eastern grey squirrel continues to survive and thrive in the urban environment and will do so for many generations to come.

 - Daniel Hall

Bibliography

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