Part 15

M-206 M 8-1/2 Wolves Jan. 1969 Light necrosis around base of teeth

M-218 M 3-1/2 Wolves Feb. 1969 Large lump in left diastema apparently from healed fracture

M-228 F 11-1/2 Wolves Mar. 1969 Heavy necrosis around molars and extending into bone; half of each M_3 destroyed, both roots and crown

M-236 F 14-1/2 Wolves Feb. 1969 Light necrosis around base of teeth

M-402 F 10-1/2 Hunters Nov. 1968 Heavy necrosis and lumps on both sides of mandible --------:---:------:--------:-----------:-----------------------------

FOOTNOTES:

Not including dental abnormalities, which are described in table 5.

The following organs were excised from wolf-killed deer and examined grossly in the field for parasites and abnormalities (fig. 12): lungs (six animals, normal); heart (seven animals, normal); liver (four animals, one small unidentified tapeworm cyst). Twin fetuses were found in each of two adult does examined.

Twelve deer were checked for body fat in one or all of the following areas: back (subcutaneous), kidneys, heart, omenta. Of these animals, seven had large amounts of fat, but five were almost depleted of fat from these stores. These five were all killed in February or March 1969; three were fawns, and two were yearlings that had not yet shed their deciduous premolars.

Of 69 animals examined for femur marrow condition, two had fat-depleted marrow. One was a fawn killed in March 1969 that had not shed its deciduous first incisors, and the other was a 5-1/2-year-old buck killed in February 1966.

A fawn and a yearling that had died in February 1969 from unknown causes also had fat-depleted, marrow. These animals might have been killed by wolves, for wolves had fed on them. However, they could have died from malnutrition and been eaten as carrion.

Table 7.--Pathological conditions in the lower limbs of deer killed by wolves or hunters

--------:---:-----:------:-------------------------------------------- : : :Cause : Specimen:Sex: Age : of : Condition number : : :death : --------:---:-----:------:-------------------------------------------- Years

M-28 M 5-1/2 Wolves Right hind foot: "Old healed ankylosis of the pastern joint ... a spontaneously healed bacterial arthritis with the destroyed joint cavity filled in by solid bone. This deer probably had defective gait" (fig. 14).

M-29 F 5-1/2 Wolves Front foot: "A 3x4x5 cm. fibrous mass in the subcutis about the digital flexor tendon on the volar surface of the metacarpus. The surface was denuded, ulcerated, and superficially infected by surface bacteria.... Probably did detract from the animal's speed of flight" (fig. 15).

M-37 F 7-1/2 Wolves Hind foot: "Probable that the lesion was at one time an active bacterial bone marrow infection that had eventually fistulated to the skin.... Regional tendons and their sheaths were also present among this inflammation and scarring, and it would be fair to assume that the animal's agility was impaired to some extent."

M-115 M 4-1/2 Hunter Right front hoof: Broken at tip.

M-196 F 4-1/2 Wolves Left front foot: "Two severe transverse lacerations on the volar surface. Each was approximately 4 cm. in length. One was located at the margin of the heel, and the other was located several cm. proximad. The more proximal wound had severed the flexon tendons, and the consequent uselessness of the limb was suggested by the splayed toes, the unmarred hoof wall and unworn soles" (fig. 16).

M-227 M 9-1/2 Wolves Left hind leg: "A diffuse swelling of the distal metatarsal bone, the surface of which was studded with small osteophytic spicules. The major flexor and extensor tendons were forced to assume a convex course over the summits of the dorsal and plantar surfaces of the defect, but the tendon sheaths were clean and the normal wear on soles of the involved toes suggested that functional deficit and pain were probably minimal ... quite certainly a callus from previous fracture" (fig. 17). --------:---:-----:------:-------------------------------------------- 1 FOOTNOTES:

D. M. Barnes. Personal correspondence to L. D. Mech, April 11, 1967.

D. M. Barnes. Undated laboratory report transmitted to L. D. Mech in 1969.

DISCUSSION AND CONCLUSIONS

It has been established that wolves hunting Dall sheep (Murie 1944), caribou (Crisler 1956), moose (Mech 1966a), and other species usually have a low percentage of success. In the case of a pack of 15 wolves hunting moose on Isle Royale during winter, only 4.6 percent of all the moose detected by the pack were killed; considering only the moose that the wolves caught up to or held at bay, the kill rate was 7.6 percent (Mech 1966a).

What little evidence there is about wolves hunting deer indicates that the success rate is also low with this prey species, at least in winter. The senior author has now observed a total of 14 deer being chased by wolves in northeastern Minnesota, mostly by packs of five, seven or eight wolves (Mech 1966b, and see Mech et al., p. 1). In only one case (6.7 percent) did the wolves (a pair) succeed in catching their prey.

Low hunting success rates imply that the circumstances influencing hunts are seldom favorable enough, or the prey animals encountered are seldom vulnerable enough for the wolves to succeed. When the evidence cited earlier that most wolf-killed animals are inferior members of their populations is considered, the most cogent explanation for the low hunting success of wolves is that relatively few prey animals are vulnerable.

Table 8.--Incidence of various abnormalities and pathological conditions in wolf-killed deer compared with that in hunter-killed deer

#: Number %: Percent

---------------------:----------------:----------------:------------- : Wolf-kills : Hunter-kills : :------:---------:------:---------: Level of Condition : Deer : Deer : Deer : Deer : significance : in : with : in : with : :sample:condition:sample:condition: ---------------------:------:---------:------:---------:------------- # # % # # % %