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Mummert 1 Alison Mummert Huey Huynh Biology 103 28, November 2012 Pa Northern Flying Squirrel Unless Pennsylvania’s residents enjoy walking through the woods at night, they probably have never seen a Northern flying squirrel. One reason is because these small mammals are nocturnal; but another reason why Pennsylvania residents are losing the opportunity to view these acrobatic creatures, is due to the fact that Pennsylvania’s carrying capacity has become very low for the Northern flying squirrel. This is causing these squirrels, which are unique compared to the other squirrels in PA, to become extinct. It is important that we raise awareness about the Northern flying squirrel, because these acrobatic creatures plays an important role in several ecological services; however this endangered species is becoming extinct in Pennsylvania due to several environmental factors. Northern Flying Squirrel Mummert 2 Although the Northern flying squirrel cannot actually fly, it has as a special niche that makes them unique. These squirrels have the ability to glide through the trees. A special characteristic of this squirrel is that they have skin flaps between their wrists and ankles. This gives them wing like characteristics, enabling them to glide from tree to tree. The Northern flying squirrel most fluent way to get around is to travel through the trees. They are also equipped with a long, broad, flattened tail which they use to steer. As the Northern flying squirrel jumps from tree to tree, it can glide up to sixty-five feet at an average speed of eight miles per hour. The Northern flying squirrel has a small body, measuring eight to eleven inches long and weighing between three to five ounces. Its fur is light brown with white fur on its belly. These characteristics make them different from other squirrel found in Pennsylvania. The Northern flying squirrel only has one litter per year, of only two to four offspring. Because of this, I would consider the Northern flying squirrel to be a k-selective species, although the gestational period of this squirrel is only a little over a month. When the baby squirrels are about three months old they take their first flight test. They reach sexual maturity when they are a year old, and in the wild they only live an average of three years. This low biotic potential, contributes to its low growth rate, which is one factor why the Northern flying squirrel population size is not growing. baby squirrels Mummert 3 Northern flying squirrels are found in Northern Pennsylvania and are native to Canada. A few studies have shown that areas in Pennsylvania, which were once populated with Northern flying squirrels, are shrinking. One study showed that the population density totaled thirty-three. A few areas where the Northern flying squirrel has been found includes the Pocono region, Warren county and Potter county. Range of Northern Flying Squirrels The Northern flying squirrels has very specific biome preferences; they are found mainly in mature conifer forest. Large mature forest provides them with many old tree cavities to build their nest, and to glide through. The Northern flying squirrels are considered to be herbivores. Their diet consists mainly of fungi; although they will sometimes eat nuts or seeds. Unlike other squirrels, these squirrels do not hoard food, and they do not hibernate during the winter months, but are active year round. This specific biome provides them with a sustainable environment. Some say that the Northern flying squirrel offers very little ecosystem services, however their unique gliding ability adds to Pennsylvania's biodiversity. It has also been theorized that their diet of eating of fungi, is an ecosystem service that benefits the health of the trees. They are unable to digest the fungal spores, which are then spread Mummert 4 on the ground, in their droppings. This aids in the seeding the fungi around the trees. Fungi have a symbiotic relationship with trees. Fungi enhances the trees ability to take in nutrients and water. This is very important since the conifer ecosystem is already fragile at this time. Also, the hemlock trees provide many ecosystem services with are important to Pennsylvania. They provide shade, which keeps streams cool. This provides a healthy environment for fish and other organisms in the stream. The Northern flying squirrel is considered a keystone species, when considering the ecosystem services they provide to the trees. The decline of the Northern Squirrel will have a wide impact on many ecological systems. Hemlock trees There are several theories about what maybe contributing to the gradual extinction of Northern flying squirrel in Pennsylvania. It is thought that the main threat to the Northern flying squirrel is the loss of mature forest in Pennsylvania. This is mostly due to human impact through the increase of development. Another reason for the decline in environment conditions is that Pennsylvania's hemlock trees are being destroyed by the hemlock wooly adelgid, which is an invasive species. This insect has severely damaged the hemlock trees. Without these trees the Northern flying squirrel has lost several important biotic characteristics that it depends on to survive. These Mummert 5 trees provide them with a place to live and travel through. They also protect them from predators, and their favorite food grows around trees. Without the hemlock tree their carrying capacity is lowered. Another factor contributing to the decline of the Northern flying squirrel is that the Southern flying squirrel, which was once endemic specie of the south, is now common all over the eastern U.S. The Southern flying squirrel's environmental resistance is very high, giving them the ability to live almost anywhere. This characteristic of the Southern squirrel allows for natural selection to occur. Recently it has been found that the Southern flying squirrel is now intermingling with the Northern flying squirrel. This is causing interspecific competition between these two squirrels. The Southern flying squirrel is not considered a direct predator, or an invasive species, but it definitely does not have a mutuality relationship with the Northern flying squirrel. It is believed that the Southern flying squirrel is a carrier of a parasite. This parasite does not harm the Southern squirrel, but appears to be harming the Northern flying squirrel. The Northern flying squirrel is not coevolving with its new neighbors, (the Southern flying squirrel) but often becomes weak and sometimes dies. Southern squirrel Mummert 6 Another reason that the Northern flying squirrel is endangered is because the Northern flying squirrel is low on the food web. A few of the Northerner flying squirrels predictors include owls, hawks, foxes, raccoons, house cats, and snakes. Because the squirrels are active during the winter months, they are more venerable during this time when predator’s food web has been slightly changed. In 1971 the Northern flying squirrel was listed as endangered under the Endangered Species Act, and in 2007 they were listed as a threatened species in Pennsylvania. One federal state wildlife project by Wilkers University and Penn State Altoona, monitored more than 500 nest boxes. Their goal was to gather population and reproduction information, due to the lack of research on the Northern flying squirrel. What can be done to save the Northern flying squirrel, most people are not even aware that this squirrel even exist? The first thing we need to do is to raise awareness about this squirrel and educate the public about the important ecosystem services it provides for our environment. This could be done by starting with educating young children in the schools, through nature assemblies about the Flying squirrel. Also, since the main threat to the Northern flying squirrel is the fragmentation of mature forest, it would benefit this squirrel if we protected older forest from being destroyed. One way would be to increase protection of the hemlock trees. You often hear people talk about “saving the trees,” but you do not hear them talk about saving the Flying squirrels. The protection of the hemlock trees would serve as an umbrella specie. This would provide the biome needed for the Northern flying squirrel to survive. It would also be beneficial if research was done to verify that parasites from the Southern flying squirrel are harming the Northern flying squirrel, and what can be done to protect them from this parasite. Mummert 7 Working to protect the Northern flying squirrel will in return have many environmental benefits. Pennsylvania residents need to find a sustainable solution, to provide a health biome for the squirrel and PA’s growing population. Overview of PA’s Northern Flying Squirrel Low biotic potential Low growth rate Lifespan 3 years K-selective Weight 3-4 lb Length 8-11in Biome- Old Forest Herbivores Niche-gliding Ecosystem service- aid trees Environmental resistance low Endangered Species -Human impact -Decline of health of forest -Southern Flying Squirrel Carrying capacity-low http://www.rps.psu.edu/indepth/flyingsquirrels.html www.portal.state.pa.us/775666/northernflying squirrelpdf Habitat Characteristics and Revised Gap Landscape Analysis for the Northern Flying Squirrel, a State Endangered Species in Pennsylvania (HACC database)