Our friend Norm Bishop responded to my questions concerning the pictures posted of two Coyotes taking down what to the naked eye appeared to be a healthy White tailed Buck..............Norm provides some insightful data regarding Coyotes ability to take down adult deer............." I also recall a talk by Dave Mech in the 1980s, saying he had never examined a deer carcass killed by wolves that didn't have some predisposing factor: lungworms, other parasites, arthritic hooves, badly worn or infected teeth, etc. Do we know this deer had acute eyesight? Did we test his hearing? How about his aerobic capacity?"..........Norm also cites a Crabtree/Sheldon 1999 Yellowstone study that stated: "Coyotes usually kill ungulates that are weak, impaired, domesticated, or starving, but they are certainly capable of killing healthy adults, even elk in Yellowstone" (Gese and Grothe, 1995, Crabtree unpublished data).

---------- Forwarded message ----------
From: Norman Bishop <nabishop@q.com>
Date: Wed, Dec 14, 2011 at 9:59 AM
Subject: More on coyotes
To: Rick Meril <rick.meril@gmail.com>

Late last evening, I wrote:

Hi, Rick.

"Prime condition" is an interesting subjective term.  I see the date on the photos is August 1, and that the buck's antlers are still in the velvet, so sensitive, and probably not comfortable as fighting tools.

 I also recall a talk by Dave Mech in the 1980s, saying he had never examined a deer carcass killed by wolves that didn't have some predisposing factor: lungworms, other parasites, arthritic hooves, badly worn or infected teeth, etc.  Do we know this deer had acute eyesight?  Did we test his hearing?  How about his aerobic capacity?

 It shouldn't surprise us that two determined coyotes can kill a white-tailed deer.  In Yellowstone, two 30-pound adult coyotes (They're not bigger than that.  Large numbers have been weighed.) can and do kill elk (mainly in late winter), that are three times the size of a whitetail. -No need for these coyotes to be hybrids.

Norm B.

I thought I should give you the source of that information about coyotes killing elk.  It is Crabtree, Robert L., and  Sheldon, Jennifer W.  1999.  Coyotes and canid existence in Yellowstone.  Pages 127-163 in Clark, Tim W., A. Peyton Curlee,  Steven C. Minta, and  Peter M. Kareiva.  Carnivores in Ecosystems: The Yellowstone Experience.  Yale University Press.

They began an intensive long-term study of coyotes on Yellowstone's northern Yellowstone elk winter range in 1989.  On P. 134, they write, "Coyotes usually kill ungulates that are weak, impaired, domesticated, or starving, but they are certainly capable of killing healthy adults, even elk in Yellowstone (Gese and Grothe, 1995, Crabtree unpublished data).  Impacts of coyotes on ungulate populations  appear to be mainly via predation on ungulate neonates during pup rearing.... In Yellowstone, coyotes kill more elk calves (neonates and older calves in winter) than do grizzly bears and mountain lions combined (Table 6.2) and inflict heavy predation (greater than 80 percent) on radio-tagged antelope fawns (D. Scott 1994.  Personal communication)."

Table 6.2 shows that 400 coyotes killed 750 neonate calves, 360-626 short yearlings, 20-35 adults in winter, and no adults during non-winter, for a total of 1120-1411, amounting to elk biomass of 66,760kg/year.  On P. 148, they write that [pre-wolf, of course] "The coyote is the major elk predator on the northern range, killing an estimated 1,276 elk annually, the majority of which are neonates..."  They also looked at general food habits of coyotes, and found by examining their scats, microtines made up 41.3%, pocket gophers 24.5%, ground squirrels 3.0%, snowshoe hares 4.4%, and elk 21.2%.

The Gese and Grothe 1995 paper is Gese, E.M., and S. Grothe.  1995.  Analysis of coyote predation on deer and elk during winter in Yellowstone National Park, Wyoming.  American Midland Naturalist 133:36-43.  

Norm B.