Methods of kill depend upon the size and 

 condition of the prey. On occasion, one wolf will 

 grab the prey by the nose while others attack 

 from behind. They feed side by side and gorge up 

 to 4.5 kg per day (Mech 1975). They can go 

 several days without eating (Mech 1966). Remains 

 of the kill are often left, but wolves seldom return 

 (McBride 1978) unless they are in poor condition, 

 extremely hungry, or feeding pups (Young and 

 Goldman 1944). 



Hunting success, studied by Mech (1966) on 

 Isle Royale, Michigan, indicated that less than 

 8% of attacks on moose by wolf packs were suc- 

 cesful. Kolenosky (1972) estimated that 25% and 

 63% of deer hunts were successful on two winters 

 in Ontaria, although these values might be in- 

 flated. Wolves in Alaska appear to take prey in 

 proportion to its abundance, and are highly suc- 

 cessful. When conditions such as deep snow or 

 abundant prey are present, they kill in excess of 

 their needs (R. Rausch, personal communication). 



SHELTER REQUIREMENTS 



See NESTING OR BEDDING. 



NESTING OR BEDDING 



Ryon (1977) describes the den-digging of a 

 captive wolf. The work was started in April and 

 May, with the female doing most of the work 

 (although on one occasion, the male was observed 

 doing most of the work). Three dens had lengths 

 from 138 to 183 cm, widths of 36 to 41 cm, and 

 heights of 31 to 38 cm. All had domed roofs with 

 somewhat restricted entrances . 



Wolves often occupy fox dens or make dens 

 in hollow logs, rock caves, bases of trees, or sides 

 of hills (Murie 1944, Young and Goldman 1944, 

 Joslin 1967). Many dens are located in sandy soils 

 and may be in spots where there is limited visibili- 

 ty or on slopes where there is a clear view of the 

 surrounding terrain (Young and Goldman 1944, 

 Jordan et al. 1967, Joslin 1967). 



Photographs of dens appear in Murie (1944) 

 Young and Goldman (1944), Mech (1966), and 

 McBride (1978). 



RITUAL REQUIREMENTS 



Not known. 



OTHER CRITICAL ENVIRONMENTAL 

 REQUIREMENTS 



The wolf territories studied in Superior Na- 

 tional Forest, Minnesota, ranged in size from 125 

 to 310 km^ (Mech 1974b). Territories in Alaska 

 and Canada, however, cover a greater range of 

 areas (R. Rausch, personal communication). 



A pack will travel its territory irregularly, but 

 will cover most areas every 3 weeks or oftener in 

 Superior National Forest. Boundaries are scent- 

 marked (Peters and Mech 1975). Mech (1974b) 

 found that lone wolves have a nomadic range over 

 a large, nonterritorial area and attempt to avoid 

 packs. 



Maximum wolf densities on Isle Royale in 

 Lake Superior, Algonquin Provincial Park, On- 

 tario, and Superior National Forest have been 

 estimated at one wolf per 2,590 ha. Wolf density 

 can be much compressed in areas of very high 

 prey density, such as parts of Canada and the 

 eastern edge of the Superior National Forest 

 (Kuyt 1972, Mech 1974b). 



POPULATION NUMBERS AND TRENDS 



On Isle Royale in Lake Superior, R. Linn 

 (personal communication) reports that there are 

 40 or more wolves. Mech (1977a) estimates 1,000 

 to 1,200 in Minnesota. R. Ream (personal com- 

 munication) reports that from 10 to 20 can be 

 found in the extreme northern Rocky Mountains 

 of Montana. Wisconsin is believed to have a few 

 (Anon. 1977), and there are perhaps six in the 

 Upper Peninsula of Michigan (Hendrickson et al. 

 1975). 



Mech (1977b) and R. Rausch (personal com- 

 munication) estimate that wolves number 10,000 

 to 15,000 in Alaska and 17,000 to 28,000 in 

 Canada. Fewer than 50 adult wolves probably sur- 

 vive in Mexico (McBride 1978). 



Murie (1944) recorded a decline in wolf num- 

 bers which he was unable to explain in Alaska 

 from 1916 to 1925; he suggested that disease may 

 have accounted for it. 



Numbers in Minnesota increased following the 

 prohibition of aerial hunting in 1950, curtailment 

 of wolf control programs in 1955, and repeal of 

 bounties in 1965. However, between 1968 and 

 1970, the Superior National Forest population 

 decreased 32% based on the 1967-68 numbers, 

 and 55% based on the 1969-70 numbers. This 



