What Happened to the Red Squirrel Midwest Population?
A hiker at Sand Ridge Nature Center in Chicago recently spotted a rare creature: a red squirrel. The squirrel was climbing a long-needled pine tree. The hiker isn’t sure if the animal is a male or a female. The sighting marks the first red squirrel sighting at the park in six years. The red squirrel used to be a native species of the northeastern quadrant of Illinois.
Intensive hunting has been the cause of an unfortunate decline in red squirrel populations in the Midwest. Since the 1970s, when they were considered pests in England, hunting for the furry rodent has been a widespread practice, even in rural areas. While some hunters are to blame for the decline in red squirrel populations, others say that hunting is simply part of nature’s process. In southeastern Minnesota, the hunts took place in the Carlos Avery Wildlife Management Area, just north of the Twin Cities.
The upper Midwest is no different. In the 2010-11 season, nearly 40,000 Minnesota hunters pursued squirrels, an increase from the year before but a steady decline from the previous season. While hunters are now outnumbering red squirrels, the problem remains. Some of these hunters are buying hunting licenses from other states, which could be a factor in the dwindling population.
In the Midwest, a small number of red squirrels are still surviving an epidemic of the zoonotic virus ‘Pox.’ The outbreak is not the worst disaster in squirrel history. While it has killed many grey squirrels in England and Wales, this epidemic has been particularly devastating for reds. Since the introduction of North American grey squirrels into the region in the 19th century, reds’ numbers have decreased dramatically. While grey squirrels are naturally resistant to the disease, red squirrels can carry the virus in their blood. The virus is transmitted by infected squirrels, and if it has not been treated promptly, the infected animals will succumb to the disease within two weeks.
As with humans, contact with infected skin or crusts is necessary for the spread of the virus. Although squirrel pox does not pose a threat to humans, it is a good idea to wash your hands after handling any animal, including pets. This disease affects red squirrels in isolated populations, which restricts the genetic diversity of the local population. If a large number of squirrels in a single population are infected, the number of infected squirrels may plummet. However, satellite populations may fill in losses.
In many regions of the United States, a significant portion of the red squirrel’s food comes from hazel trees, which are regularly coppiced. Coppicing is the practice of cutting back trees so that new shoots can grow. This method has been used for centuries to provide wood for buildings and other uses. Hazel trees are particularly beneficial to red squirrels because they provide a plentiful source of nutmeg.
Postfire seedling establishment is rare and requires excavation of underground organs to differentiate seedlings from sprouts. Seedlings established on burned sites may have been dropped by rodents, as evidenced by early plant succession studies. Despite these findings, further research is necessary to document the frequency of postfire seedling establishment in the United States. In addition, it is possible that a small percentage of postfire seedlings could be the result of animal caches.
In the early 1900s, the red squirrel went extinct from the midwestern United States. But about 70 years later, these animals started returning to Illinois. Researchers at Eastern Illinois University studied the new population and those from neighboring states. They determined that the Illinois red squirrels probably migrated from Michigan and Indiana. The new red squirrels may have contracted the disease from the grays. They are also less prolific breeders.
In order to increase the population, a female red squirrel must be in estrus. During this time, she ventures out of her territory, possibly advertising her upcoming estrus. In a typical year, she raises two litters of young. The red squirrel diet includes a variety of foods, such as acorns, osage orange fruits, nuts, and seeds. They also store food in cavities and shallow ground.
The gray and red squirrels have been at war with each other for decades, and the recent emergence of a disease that kills them is devastating to the midwest’s red squirrel population. Although these two species have been closely associated for centuries, there are some important differences between them. Gray squirrels are not as aggressive as red squirrels and are not as prolific breeders. They are also more adapted to living in broadleaf forests. According to a 1930 report from Oxford University, the gray squirrels can expand their range by 34 square kilometers annually, 25 times faster than the red squirrels.
Studies have shown that the Red Squirrel uses habitats that contain high concentrations of black walnut and soft mast. They avoid conifers, which reduce their chances of survival. The use of these two species correlates with their home range. This shows that the quality of habitat is important for red squirrels. Red squirrels have a high demand for food, and many of the trees that they consume have been destroyed.
Reintroduction of gray squirrels
Reintroducing grays to the red-squirrel midwest population has long been on the agenda for many wildlife conservation organizations. Red-squirrel populations are severely threatened by a virus that decimates them. The IUCN red list lists red squirrels as “Least Concern.” However, the red-squirrel population in Britain is drastically reduced due to the introduction of eastern grays. This disease wreaks havoc on the red squirrel population because greys outcompete their smaller counterparts.
Grey squirrel populations were once abundant in the mid-19th century. However, their high levels of damage to flower gardens, tree saplings, and bird nests made them undesirable. As a result, the U.K. Parliament banned their introduction to the country in 1937. However, advocates of gray squirrel reintroduction hope that the species can be reintroduced to the red squirrel population and the species will thrive once again.
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.