Sunday, May 29, 2011

Pennsylvania Whitetail Deer-Coyote Depredation and Organized Coyote Hunts A Problem?

Coyote Hunting Mice In Cades Cove  Great Smoky Mountains National Park
The Eastern Coyote is a controversial creature with many believing that they, along with long deer seasons and high antlerless license allocations, have caused the whitetail deer population in some areas of Pennsylvania to crash to unhuntable levels.  Many believe that the Pennsylvania Game Commission and, or auto insurance companies have stocked coyotes to destroy the deer population, but  others point out that this seems unlikely as there is no closed season on shooting coyotes except with certain exceptions during bear, deer, and spring turkey season, and there is a liberal trapping season also, which would not be consistent with attempting to establish large populations of the animal.  The problem has attracted so much attention that some organizations such as the Mosquito Creek Sportsmen's Club hold annual coyote hunts, which has a $10.00 entrance fee, $8.00 of which goes toward prize money and $2.00 for administration costs. 3,541 hunters registered in 2011 and a total of 178 coyotes were taken during the hunt. $34,868 was paid in prize money, with the first place winner for heaviest coyote receiving $7,082.00.

Late this past February I received information from blog reader and hiking enthusiast Terry Shore Davis, about concerns that organized coyote hunts may be actually having a negative impact on the deer herd. She has a friend by the name of Betty Detsch that she hikes with on a fairly regular basis, who also is a deer hunter, but is primarily a hiker now. According to Mrs. Shore, "Detsch is concerned that deer are stressed and are at their weakest in the winter. Then the coyote hunt starts, and with hunters’ drives, hunters are (unconsciously) driving the deer also. With the ice and snow conditions, deer easily break their legs and die. Because she is in the woods nearly every day, she has told me she has walked in the wake of hunters’ drives and has found dead deer. She adds that she is not opposed to the hunt per se, but that it should be held a different time of year, when the conditions for the deer would be better." At this point in time Ms. Detsch had written a letter to the editor of the St Marys newspaper expressing this view, but I ams not certain at this point if it was published. Whatever the case she does raise a point that I had not thought about and it would be good to know if any blog readers have first hand knowledge of similar problems. This also leads one to consider  if coyote depredation of whitetail deer is in fact a serious problem.

According to most published material about the animals, coyotes feed  primarily on small mammals such as mice, squirrels, and rabbits, etc. A fawn survival study conducted by the Pennsylvania Game Commission in 2001-02 showed that predation is responsible for about 46% of fawn mortality during the first eight months of life.  Coyotes were responsible for 36.7% of the deaths, while black bears accounted for 32.7% of deaths. Another 27% of the fawn population succumbed to diseases and other natural causes. Source:  Survival rates, mortality causes, and habitats of Pennsylvania white-tailed deer fawns Justin K. Vreeland, Duane R. Diefenbach, and Bret D. Wallingford 

In light of this, I was surprised to read an article published by  "PA Coyotes Not Decimating Deer Herd, Expert Says".  It is from the Penn State News Service and was published 03/16/2010.  I cannot find the name of the author, but the article is constructed around a series of quotes by Duane Diefenback, who is described as  adjunct professor of wildlife ecology and leader of the Pennsylvania Cooperative Fish and Wildlife Research Unit housed in the college’s School of Forest Resources", He  of course is the same person who was involved with the fawn survival study listed above.

According to Diefenbach, "There is no question the coyote population has grown dramatically in the Northeast in recent decades, and everyone agrees that coyotes do prey on fawns, “but our data tell us that coyote predation is not an issue in Pennsylvania.” He goes on to say a bit later in the article that,“Significantly, very, very few adult deer in our studies have succumbed to predation from coyotes, bears or anything else,” he said.  He goes on to say, “We now know that in this state, once a deer reaches about 12 months of age, the only significant mortal dangers it faces are getting hit by a car or being harvested by a hunter. By far, most of the time when a coyote eats venison, it is from a road-killed animal, or from a deer that was wounded by a hunter but not retrieved.” "We know fawns often are killed and eaten by coyotes and bears, Diefenbach said, "but that has always been the case."

He goes on to make the point that Pennsylvania does have coyote depredation, but it is no more than in other states  and it is not extraordinary.  

Fawns Are Especially Vulnerable During First Few Weeks Of Life
From a personal standpoint, the first I positively knew coyotes were in Fulton County, PA was in 1995 when  PGC Maintenance Supervisor Billie Cromwell  videotaped  one in the southern part of the county during deer season.  I  encountered them in Elk County that same year,  and later saw several in Cades Cove in the Smokies, and Shenandoah National Park in Virginia.  I have also seen quite a few in Fulton County during the past few years and have heard them howling at night there, and during the day in Virginia.  I have not seen a coyote attack a deer, but have seen one predation incident in which I think they were the likely culprit, although it could have been done by a bobcat.

Late Winter Predation Incident

If you look in the distance in the photo above you can see a scattering of hair where the deer was killed and then dragged a substantial distance.  I  found this at 8:30 in the morning, and it was not warm, but yet had been done fairly recently as the blood was still bright red and not black from drying, which indicated it happened at night. This tended to rule out the Golden Eagle, which is known to attack deer,  as an alternative possibility.  If one spends a substantial amount of time in close proximity to a herd of deer like I do, it is easy to tell when they are having problems with predators.  I have been near to deer that were feeding peacefully and suddenly another deer would walk over the top of a hill and the herd that was grazing would bolt instantly when they heard the grass swishing under the arriving deers hoofs and run  away for a distance before turning to ascertain if there was an actual threat and when they determined it was another deer, they instantly returned to grazing.  I have seen these same deer be very alarmed when they see a coyote passing through the meadows several hundred yards away.  There are substantial periods of time though that they do not run at the sound of other deer approaching, which leads me to believe that they are being attacked on a regular basis during the periods that they are so skittish, which are usually in the summer. 

I am in almost daily contact with this herd and can identify all of the animals on sight and can tell which does have fawns, and there is usually a significant loss of fawns each year that cannot be explained.  One will see a doe with  a fawn and then one day the fawn does not appear and the doe's udder gradually shrinks, which indicates she is no longer nursing. 

As I mentioned previously, coyotes are not the only predators which kill deer.  A few years ago I was by a meadow on an early June morning after most of the fawns had been born.  A large herd of does was feeding in the meadow and I was on watch with my cameras.  Suddenly I heard a loud, chilling scream behind me and about 100 yards away. At the sound, the deer froze, looked about with fear plainly visible on their faces and then the does that had fawns dropped into a crouch and quickly scattered going into the woods at different points. When I had time to analyze the situation it seemed likely that each was returning to where their fawns were hidden and were going to try to defend them in case of attack.  From my position, I could  see the lane that came from the public road into the property and there was a doe and fawn walking out the lane.  I swiveled the camera with 500mm lens around tried to get a photo of them, but light levels were low and there was some intervening brush, which made it difficult to get a clear shot, and the deer walked into the woods and out of sight.  No sooner had they vanished than a monstrous bobcat came walking down the public road and turned into the lane, walked a short distance and vanished into the woods.  This happened much quicker than it takes to read it and I never came close to getting a photo, but I can see this in my mind yet today as thought I were looking at a film clip of the event. Billie Cromwell also actually saw a black bear kill a fawn at Big Meadows in Shenandoah National Park, but we will save that story for another day.

I think there is little doubt that most outdoors people like to see a coyote--hunters and trappers like to pursue them, and photographers like to photograph them, but many have mixed or negative feelings about them  killing fawns.  Mr. Diefenbach may claim they are not decimating the deer herd, yet according to the Fawn Survival Study, 46% of fawn mortality at eight months of age is due to predation and coyotes were responsible for 36.7% of the deaths.  Unless I am missing something, it does seem glaringly obvious that they do have a significant impact, but does this justify allowing organized coyote hunts during the winter months that may unduly stress or otherwise injure deer?

Originally posted at Pennsylvania Wildlife Photographer by Willard Hill

1 comment:

Ken Conger Photography said...

Great read! I do not know the facts about PA mortality, but I can assure you coyotes take their toll on fawns in VA. I have also heard coyotes and once a bear take fawns in Shenandoah NP, but never witnessed the incident. Great Histograms Willard.