How Much Heat Can a Squirrel Tolerate? 
What is the body temperature of a squirrel? The following article will give you an insight on the mechanisms by which ground squirrels regulate their body temperature. This article also looks at how a thirteen-lined ground squirrel survives Winter. If you are interested in the behavior of a ground squirrel while it is hibernating, you might also like to read more about hibernation. But first, let’s see how much heat can a squirrel tolerate.
Winter survival of the thirteen-lined ground squirrel
The thirteen-lined ground squirrel is native to grasslands and prairies in western and northern Missouri. In late summer, it puts on a thick coat of fat and stores it in its burrow. From October to April, it retreats to its burrow to hibernate, where it lives with its young. The squirrels reduce their breathing rate to one breath every five minutes and close the openings before winter sets in.
To study this transition to winter, researchers implanted data loggers in thirteen-lined ground squirrels. During their stay in the hibernaculum, the animals undergo a series of torpor patterns that converge on maximizing torpor duration and decreasing euthermy between bouts of torpor. Researchers have found that torpor expression varies considerably among animals, but it generally coincides with the environmental light-dark cycle.
Body temperature of a hibernating arctic ground squirrel
In order to survive the cold winter months, arctic ground squirrels retreat to their burrows, which can be a meter or more below the tundra. Their bodies cool down to minus two degrees Celsius, their heartbeat slows to a single beat every fifteen seconds, and their breathing stops for several minutes at a time. This process of reduced metabolism allows their cells to endure a severe lack of oxygen and blood.
The lowest body temperature of any mammal is reached during hibernation in the arctic ground squirrel. This is due to the fact that their core body temperature is significantly below freezing, but their brain temperatures remain above freezing. During this time, arctic ground squirrels shiver for twelve to fifteen hours a day to raise their body temperature to normal levels of 98 degrees Fahrenheit.
Mechanisms by which ground squirrels regulate their body temperature
The hypothalamus, a part of the brain, controls the ground squirrel’s temperature. This endocrine system is responsible for maintaining the ground squirrel’s body temperature between 98.7 and 102.3 degrees Fahrenheit. While the average human’s body temperature is about 28.7 degrees Celsius, the ground squirrel can maintain a lower body temperature of 32-33 degrees Celsius for weeks at a time.
Although all mammals have nucleators in their blood, arctic ground squirrels use a different strategy to avoid freezing and maintain varying body temperature. They purge their bodies to eliminate any remaining nucleators, which helps them maintain body temperatures that are relatively consistent. While their heart rates are very low, they periodically cease breathing. While their blood plasma is similar to human blood, it lacks an antifreeze component.
At higher ambient temperatures, the arctic ground squirrel’s heart beats 200-300 times per minute, while during torpor, it slows to three or four beats per minute. During torpor, the ground squirrel’s breathing becomes episodic, consisting of five or 10 breaths followed by apnea. The slowed heart rate decreases the blood flow to the brain by about eighty-nine percent. This reduces the blood flow to the brain within minutes.
Behavior of a hibernating arctic ground squirrel
The behavior of an arctic ground squirrel while hibernating is not understood. They periodically arouse during the day to raise their body temperature, a practice similar to that used by humans. They also lose weight during this period, particularly females. However, this loss of weight is not as dramatic as that of males. The researchers are working to understand the mechanism that enables arctic ground squirrels to regulate their body temperature.
In most small mammals, hibernation is an act of conserving warm blood and turning down the body’s thermostat. The arctic ground squirrel is one of the most extreme examples of this behavior. In 1987, biologist Brian Barnes captured 12 ground squirrels in the Arctic, implanted tiny temperature-sensitive radio transmitters in their abdominals, and moved them into outdoor enclosures in Fairbanks. They then hibernated in their burrows.
How much heat can a squirrel tolerate?
A squirrel can tolerate temperatures up to around 102 degrees Fahrenheit.
At what temperature does a squirrel start to experience heat stress?
A squirrel starts to experience heat stress at around 95 degrees Fahrenheit.
What are some signs that a squirrel is experiencing heat stress?
Some signs that a squirrel is experiencing heat stress are heavy panting lethargy and dark tongue and gums.
How can you help a squirrel that is experiencing heat stress?
You can help a squirrel that is experiencing heat stress by moving it to a cool shady area and offering it water to drink.
What is the highest temperature that a squirrel can survive?
The highest temperature that a squirrel can survive is around 115 degrees Fahrenheit.
What is the lowest temperature that a squirrel can survive?
The lowest temperature that a squirrel can survive is around -20 degrees Fahrenheit.
How do squirrels keep warm in the winter?
In the winter squirrels keep warm by huddling together and by using their tail as a blanket.
How do squirrels stay cool in the summer?
In the summer squirrels stay cool by staying in the shade panting and by licking their fur.
What is thermoregulation?
Thermoregulation is the ability to maintain a consistent body temperature.
Why is thermoregulation important for squirrels?
Thermoregulation is important for squirrels because it helps them to survive in a variety of climates and to avoid heat stress.
What is the normal body temperature for a squirrel?
The normal body temperature for a squirrel is around 101 degrees Fahrenheit.
How does the normal body temperature for a squirrel compare to the temperatures that they can tolerate?
The normal body temperature for a squirrel is close to the temperatures that they can tolerate.
How does the normal body temperature for a squirrel compare to the temperatures that they can survive?
The normal body temperature for a squirrel is lower than the temperatures that they can survive.
What is the difference between the temperatures that a squirrel can tolerate and the temperatures that they can survive?
The difference between the temperatures that a squirrel can tolerate and the temperatures that they can survive is that the squirrel can only tolerate temperatures up to 102 degrees Fahrenheit before experiencing heat stress while they can survive temperatures up to 115 degrees Fahrenheit.
What is the difference between the temperatures that a squirrel can tolerate and the temperatures that they can survive?
The difference between the temperatures that a squirrel can tolerate and the temperatures that they can survive is that the squirrel can only tolerate temperatures up to 102 degrees Fahrenheit before experiencing heat stress while they can survive temperatures up to 115 degrees Fahrenheit.
Jessica Watson is a PHD holder from the University of Washington. She studied behavior and interaction between squirrels and has presented her research in several wildlife conferences including TWS Annual Conference in Winnipeg.
