Red Fox (Vulpes vulpes)

Marissa N. Webb

Biology 101

American Military University

Mr. Daniel Pettus

Red Fox (Vulpes vulpes) The red fox (Vulpes vulpes) is the largest of the true foxes. “True foxes” is a nickname for the genus Vulpes. Red foxes are the most geographically spread member of the Carnivora. Red foxes live all around the world in many different diverse habitats including forests, grasslands, mountains, and deserts. They are located across the entire Northern Hemisphere from the Arctic Circle to North Africa, Central America and Asia. I currently live in Virginia Beach, Virginia and red foxes are located throughout the local area. The red fox is found in all areas of Virginia except for the extreme southeast corner. It prefers diverse habitat, in less populated areas, like farmland. You can distinguish a red fox from other similar animals by the following physical characteristics: they are the size of a small dog, a total of 39-41 inches and a weight of 9-12 pounds. They have prominent, erect ears, a pointed nose, and a long, bushy tail with white tip. Their fur is long and soft, with the upper part reddish-yellow, black-tipped on the shoulders. Red foxes are omnivorous. Most of their diet consists of rabbits and mice. They are also known to eat poultry, squirrels, muskrats, quail, small nongame birds, insects, nuts and fruits in smaller amounts. The life cycle of the red fox is as follows: young foxes must find a territory of their own. They need a place to hunt and feed. They also need to have their own home. Because they could cross the territories of other foxes, it could take weeks or months for a fox to find their own territory. If a fox chooses to cross the territory of another fox in an attempt to claim their home, the foxes will fight. They typically lean on each other's shoulders and try to topple the other over. Normally, they do not attempt to hurt each other. The winner of the fight gets the territory. Depending on the area where the fox lives, winter could be a difficult time period due to the fact that everything is covered in snow. This leaves gives the fox a hard time finding food. Their fur does grow thicker though in the winter months to help shield the foxes from the cold. The fox searches for a mate to share it's life with. The male fox lets out long barks and the vixen shrieks loudly so that they can find each other. Following weeks of courtship and getting to know each other, the foxes do eventually have cubs. Once the cubs are born, the cycle repeats itself (http://www.foxden.nl/foxes.html ). A male and a female red fox are required for reproduction. For sexual reproduction to occur, the gametes need to conjoin in the process of fertilization. The female gametes are eggs, and the male gametes are sperm. Eggs are made in the process of oogenesis, while sperm is made in the process of spermatogenesis. The female reproductive system includes the following: vagina, cervix, body of uterus, uterine horn, ovary, and an oviduct. The egg is created in the ovary. Once the egg is mature and ready to be fertilized, it travels through the oviduct, which is where fertilization takes place. The oviduct then branches off into the uterine horn, where the oviduct and uterus meet. The uterus is where the fertilized egg will develop and grow. The cervix is where the sperm enters the body to fertilize the egg, and the vagina is the external opening out of the body through the genitals. The male reproductive system includes the following: anus, prostate gland, uretha, sperm ducts, epididymus, scrotal sac, testis, penis, glans penis, penis bone, and bladder. The sperm is created in the testis. They also store sperm in the epididymis. When the fox ejaculates, sperm travels from the epididymis through the sperm duct to the prostate for the prostate to add other beneficial liquids to help the sperm exit the body and to nurture the sperm as well. This makes a fluid called semen, which exits the body by travelling through the penis and leaving via the urethra. The glans penis is what ensure that the penis stays in the vagina during intercourse. All of this shows that internal fertilization occurs in the red fox (http://redfoxofficial.weebly.com/the-reproductive-system.html). The red fox is typically sexually mature at 9-10 months old. Though they mate from January through March, the courtship usually occurs during the winter months. Males court by fighting with each other to impress the female red foxes. The fighting can result in serious injuries, and sometimes even death. After courtship, the female fox allows the male to mount her and they have sexual intercourse. After mating, the female fox creates numerous dens to raise the cubs in. She makes multiple dens just in case the others are disturbed. The male brings the female food while she is carrying the babies. The gestation period is a little under two months; the litter can be anywhere from 1-10 pups. The mother fox nurses the babies until they are big enough to eat meat, then she regurgitates meat for them to eat. Eventually, she will bring live prey so the young foxes can learn to kill food for themselves. The young foxes typically stay in the den with the mother and father until they are about 7 months old, and then they go out on their own and begin the typical red fox life cycle. Upon the young departing, the mother and father go off on their separate ways. The evolutionary history of the red fox is not completely resolved, and it may never be due to lack of new fossil findings. Taxonomists currently believe that red foxes and other modern-day dogs, come from a medium-sized grassland predator from North America called Prohesperocyon wilsoni. It appeared during the late Eocene, some 36 million years ago. A recent study, showed that North American red foxes originated from two separate genetic lineages that were isolated from each other by glaciers some half a million years ago. One that thrived in low-elevation, human-dominated landscapes, while the other was extremely elusive and rarely seen populations that live only in isolated alpine and sub-alpine areas in the mountains of the Western United States. This evolutionary history helps to explain why foxes in some areas are much larger than foxes in other areas. Just recently, Keith Aubry, a research wildlife biologist, and his colleagues tested this hypothesis through genetic analyses of 285 museum specimens and a close examination of fossil, archeological, historical, and ecological records. They found that North American red foxes did stem from two distinct lineages that diverged from each other while they were isolated in both the southern and northern parts of the continent during the last Ice Age. Aubry also believes that montane foxes' smaller size and high-elevation habitat preference is indicative of their being descendants of ancient foxes that had inhabited the southern part of the continent.

References
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Lazyfox's Spot. (n.d.). Retrieved from http://www.foxden.nl/foxes.html
Red Fox - Vulpes vulpes - NatureWorks. (n.d.). Retrieved from http://www.nhptv.org/natureworks/redfox.htm#6 red fox. (n.d.). Retrieved from http://www.fcps.edu/islandcreekes/ecology/red_fox.htm
Red Foxes, Red Fox Pictures, Red Fox Facts - National Geographic. (n.d.). Retrieved from http://animals.nationalgeographic.com/animals/mammals/red-fox/
The Reproductive System - The Red Fox Resource. (n.d.). Retrieved from http://redfoxofficial.weebly.com/the-reproductive-system.html
We're seeing more foxes in daylight, but not to worry | HamptonRoads.com | PilotOnline.com. (n.d.). Retrieved from http://hamptonroads.com/2011/04/were-seeing-more-foxes-daylight-not-worry
Wildlife Online - Natural History of the Red Fox. (n.d.). Retrieved from http://www.wildlifeonline.me.uk/red_fox.html