Prairie dogs were once more prevalent in North America, with one area in Texas housing an incredible 400 million of these small animals. Although their numbers have dwindled, prairie dogs still build amazing underground homes.
Prairie dogs live in colonies of up to 1000 animals. They have large burrows, which each house a coterie. Many of these are built next to each other, allowing them protection from predators. They avoid overcrowding by finding or digging a new burrow. Burrows are made with two or three entrances and are ventilated using piles of dirt around the entrance.
The Great Plains once stretched over large areas of North America, with an almost endless sea of grass. This was where the large herds of bison and pronghorn antelope roamed. When the European settlers moved westwards, they brought their cattle with them, destroying the wild animals already living there.
Although the larger animals were almost wiped out, smaller animals were mainly left alone by the settlers as they didn’t destroy their crops. Prairie dogs had huge colonies in some areas, with one settlement in Texas covering an area 380km long and 160km wide. This colony was home to approximately 400 million prairie dogs, and this was just in one state, with many other states also holding large colonies.
Although these colonies of millions of animals don’t exist anymore, large colonies of up to a thousand prairie dogs live together.
Prairie dogs are not a species of dogs but a ground squirrel, part of the rodent family. Prairie dogs make a barking call to communicate, and it is this noise where they get their name.
Although classed as squirrels, prairie dogs do not have the bushy trails of the tree squirrels and have been described as looking like giant hamsters. Five species of prairie dogs can all be found in North America.
- Black-tailed prairie dog
- White-tailed prairie dog
- Utah prairie dog
- Gunnison’s prairie dog
- Mexican prairie dog
The black-tailed prairie dog is the most common, about 15 inches (40cm) long, and has yellowish-brown fur. While most other rodents live solitary lives, prairie dogs are highly social animals.
Social Lives In Burrows
Although some other rodents, such as marmots and ground squirrels, live communally, they don’t have the social organization of prairie dogs.
Prairie dogs have a society made up of a friendly clan among themselves. This society is called the coterie. The coteries consist of one adult male, two or three females, and their offspring. If there is more than one male, one is dominant over the others who keep out of their way.
There can be up to 20 young in a coterie, but these numbers dwindle as they get older until only a few adults are left. The elderly adults are taken under the wing of a dominant neighbor, although the boundaries of their burrow are not taken over.
A large portion of the prairie dogs’ day is devoted to keeping out trespassers. By defending the burrow entrances from others, they keep their coterie safe.
Dealing With Intruders
Prairie dogs will check that others are not intruding on their territory. When they meet another prairie dog, they will greet each other by kissing. They put their heads together and kiss with their teeth bared. This can turn into grooming with one rolling onto its back.
Although the kiss looks cute, it is a gesture to indicate that they will defend their territory. If they are members of the same coterie, then the kiss will allow them to recognize each other and treat each other in a friendly manner. However, if the kiss is from a stranger, prairie dogs can become aggressive. Most times, the trespasser will retreat quickly.
This is sometimes different at the boundary of a territory. If neither prairie dog knows who owns the border, they will approach each other and stop. One will turn around, raise its tail, and let the other sniff the scent glands. They then reverse roles before a small fight occurs.
After more sniffing and fighting, they will decide who controls the boundary, retreating to their respective sides.
As well as kissing, fighting, and sniffing, prairie dogs will also let others know the boundaries of their territory vocally. After a border dispute, prairie dogs can often be heard giving a loud bark. This two-note noise is harsh and is described as Ah-aaah.
The prairie dog rises on its hind legs, pointing its nose to the sky. The first note is made while inhaling and the second as it exhales. This is called the jump-yip, as they can sometimes be seen leaping into the air while making the sound.
How Young Prairie Dogs Learn
Coteries last for many years, and the infants must learn their place in the complex society. When young, prairie dogs can wander into other territories without any fear of attack, and when first leaving the nest, they meet other coterie members. Adults will groom them, and they can play with other infants of their age.
However, after a few weeks, the restrictions they face as adults come into play. They are no longer allowed to trespass into another territory and will be chased home. This is an important lesson: they will not be treated the same away from home, and they soon learn that passing the border results in harsher treatment.
A few weeks after leaving the nest, the infants will also greet others by kissing them and performing the jump-yip vocalization. If they do this in a neighboring territory, there are chased away, so they soon realize where the territory boundaries are.
How Prairie Dogs Avoid Overcrowding
After its first summer, the infant will have adapted to its social life. To stop overcrowding and ensure there is enough food in the coterie, prairie dogs have an excellent solution. While most animals are forced to leave their territory by their parents, this doesn’t happen to prairie dogs.
Breeding occurs between March and May, and they will defend their burrows, even against members of their coterie. During these months, adults that are not breeding and the young will leave their territories to find and dig new burrows.
Some may also find neighboring territories where there are not many other animals. The battles can be fierce as they try to teach the coteries to accept their presence or drive them away from their homes.
As youngsters are born, wandering adults will spend more time away from the coterie, helping to ease the overcrowding. As they spend more time in their new homes, they will only return to their old coteries for brief visits.
A prairie dog’s favorite food is the flowers and seeds of plants, although they also eat grasses. Prairie dogs will cut down plants to wither in the sun, giving them plenty of food.
Ventilation In Burrows
Prairie dogs live in u-shaped burrows measuring between 10-30 meters long and to a depth of up to five meters. Each burrow has two entrances, with a third sometimes in the middle.
At the entrances of the burrows, they use some of the expelled dirt as lookout posts. Each opening is different, with one having a low, rounded dirt rim. The other has a volcano-shaped mound, allowing them a better lookout for predators.
Although these are used for lookout, they also serve to ventilate the burrows. As the wind speed is reduced at ground level through friction, the air flow past the volcano end is greater than past the lower, rounded mound. This creates low pressure in the volcano end of the tunnel, and the air is sucked out.
This allows the air in the burrow to be changed in ten minutes. Without this marvel of engineering, the air in the shelter would not support even one of the animals.
How The Burrows Help Against Predators
Although they have many predators, prairie dogs have a better life expectancy than most other rodents. Badgers, hawks, coyotes, and rattlesnakes all feed on prairie dogs, while the black-footed ferret essentially lives on them.
As they have an efficient warning system, a young prairie dog’s chance of survival through the first year is excellent. While they do not post lookouts as meerkats do, there are enough of them for someone always to be alert. As there are so many living in these colonies, many eyes are better than one, so they don’t need to be on the lookout specifically. A jump-yip can be enough to alert others, and barks continue until the danger has passed.