What Fed?On A Dead Baby Kit Fox?
During a trip to the Adirondack Mountains in New York State in late July this year I discovered an intact dead kit fox at the edge of the woods in the back yard of the cabin friends let my wife and I stay in for a weekend. The next morning, to my shock and surprise, the young fox body was lying in the same place with its vital and essential parts completely removed. Gone were the lungs, heart, liver and intestines; the fox had been eviscerated. Ribs at the lower end of the chest and the vertebra below were clearly visible. The limbs and head remained untouched. The sight was startling. Over the next several weeks I sought an answer to what fed on this dead fox. A seasoned big game hunter and state environmental conservation officer both suggested it could be several different predators. My fellow bird watching friends thought a vulture did it. My veterinarian thought I should have examined and measured the bite pattern to help narrow the possibilities. A related approach was offered by John Rappole, a professional ornithologist, which I decided to investigate. He suggested studying dental patterns of mammals to determine which were capable of cutting, slicing and consuming the soft tissue of the abdominal and chest cavity, leaving the remaining body untouched.
Since the eviscerated fox remained where I found it the day before, a large predator was not involved because it would likely drag the fox away to feed in seclusion Therefore, I ruled out the coyote, fisher, bobcat and fox. I evaluated dental arrangement in likely mammals to determine if their teeth could cut and slice the viscera. Our own dental pattern can serve as a reference for animal comparison. Looking in a mirror, grinning widely reveals the dental pattern for one side of the upper jaw.
First, two flat teeth in front called incisors, are cutting teeth. Next, one pointed tooth called a canine, is most prominent on a pet dog or cat, holds food or prey and tears flesh. Next are two premolars or bicuspids which slice food. Finally, three molars with wide cusps function for crushing and grinding. The numerical pattern for one-half of the human mouth is designated 18.104.22.168. for the upper jaw and 22.214.171.124. for the lower jaw. Combined, the formula is 126.96.36.199./188.8.131.52. which totals 16 teeth on one side of the mouth and 16 on the other side for a total of 32 teeth.
The first potential mammal that could have fed on the dead kit fox is the ubiquitous opossum with a dental pattern 184.108.40.206./220.127.116.11. or 50 teeth in all, the most of any mammal, which includes 18 incisors to cut and 28 premolars and molars to slice and grind. The opossum is an omnivore eating plants and animals plus carrion. I was fortunate to pass a road killed opossum in October which died with its mouth open so I photographed the teeth, verifying that 50 teeth were present.
The common skunk, an omnivore, also eats carrion but avoids eating muscle. The dental pattern is 18.104.22.168./22.214.171.124 so there are sufficient teeth to cut and slice soft tissue.
The weasel, a carnivore, eats meat. The dental pattern is 126.96.36.199./188.8.131.52. indicating six incisors for cutting and six premolars for slicing. The weasel weighs 3/4 pounds so it difficult to imagine this tiny animal consuming the entire viscera.
The raccoon, known as an omnivore, prefers live prey, although they have been known to eat animal intestines. Their dental pattern, 184.108.40.206./220.127.116.11, indicates incisors to cut and premolars to slice soft tissue.
Domestic cats with a dental pattern of 18.104.22.168./22.214.171.124. also have sufficient teeth to cut and slice but, typically leave bite marks on the limbs absent on this fox.
The animal which consumed the viscera of this kit fox remains unknown. My guess is the opossum since it has 50 teeth to do the cutting and slicing of the tissue and is large enough to consume the whole viscera. Tell me what animal you think fed on the kit fox.