DRArr EIS APPENDIX 1 



(Boyd ct al. 1993). Wolves localize their movements around a den site and whelp in late April, following a 63-day 

 gestation peritxl. Wolves may be sensitive to human disturbance during the denning season. After the pups are 

 about eight weeks old, they are moved to a series of rendezvous sites. In northwest Montana, maximum litter size 

 averaged 53 (range 1-9) from 1982 to the mid 199()s. By December, average litter size declined to 4.5 (Fleischer et 

 al.l997). In central Idaho, average litter size was 5.1 from 1996-1998 (Mack and Laudon 1998). 



Pup sur\'ival is highly variable and influenced by several factors, including disease, predation. and nutrition (Mech 

 and Goyal 1993. Johnson el al. 1994). In northwestern Montana from 1982-1995, 85% of pups survived until 

 December, though survival varied year to year (Fleischer et al. 1997). Pup mortality in the first eight months of life 

 was attributed to human causes (8 of 20 mortalities, 40%), unknown causes (2 of 20, 15%), and disappearance (9 of 

 20, 45%). In YNP, during the first four years, 133 pups were bom in 29 litters and 71% were believed to still be 

 alive in 1998 (Bangs et al. 1998). Pup survival varied between 73 and 81% from 1996-1998. However, canine 

 parvovirus was strongly suspected as a contributing factor in the low pup survival (45%) in 1999. In 2000. pup 

 survival rebounded to 77% (Smith et al. 2(X)0). In central Idaho, 92-99 pups were produced between 1995 and 1998 

 (Mack and Laudon 1998). 



Occasionally, more than one female in a pack may breed, resulting in more than one litter per pack (Ballard et al. 

 1987). This phenomenon has been documented in YNP (Smith et al. 2000, USFWS et al. 2000, USFWS et al. 

 2(X)1). In 1999, one pack had two litters. In 2000, 13 wolf packs produced 16 litters. Occasionally this 

 phenomenon leads to the formation of a new pack (Boyd et al. 1995). 



Food Habits 



The gray wolf is an opportunistic carnivore and is keenly adapted lo hunt large prey species such as deer, elk, and 

 moose. Wolves may scavenge carrion or even eat vegetation. In Montana, white-tailed deer, mule deer, elk and 

 moose make up the majority of wolf diets. In northwestern Montana, white-tailed deer comprised 83% of wolf kills, 

 whereas elk and moose comprised 14% and 3%, respectively (Kunkel et al. 1999). However, 87% of wolf kills in 

 YNP during 1999 were elk (Smith et al. 2000). In central Idaho, elk (53%) and deer (42%) were the most frequently 

 detected species in scat samples collected in summer 1997 (Mack and Laudon 1998). Ungulate species compose 

 different proportions of wolf diets, depending on the relative abundance and distribution of available prey within the 

 territory. 



Wolves also prey on smaller species such as rabbits or beaver. Wolf scat collected in YNP in 1998 contained voles, 

 ground squirrels, snowshoe hare, coyote, bear, insects, and vegetation (Smith 1998). Earlier work in northwestern 

 Montana also documented non-ungulate prey species, such as: ruffed grouse, raven, striped skunk, beaver, coyote, 

 porcupine, and golden eagle (Boyd et al. 1994). 



Wolves also scavenge opportunistically on vehicle- or train-killed ungulates, winterkill, and on kills made by other 

 carnivores, particularly mountain lions. Wolves in northwestern Montana scavenge the butchered remains of 

 domestic livestock or big game animals at rural bone yards or carcass disposal sites. In most instances, private 

 individuals discard these remains on nearby public land. Some northwestern Montana packs also scavenge ungulate 

 carcasses cleared from local highways and left in a gravel pit by the Montana Department of Transportation. 

 Wolves may also kill and feed upon domestic livestock such as cattle, sheep, llamas, horses, or goats. They may 

 also kill domestic dogs but usually do not feed on the carcass. 



Movements and Territories 



A pack establishes an annual home range or territory and defends it from trespassing wolves. From late April until 

 September, pack activity is centered at or near the den or rendezvous sites, as adults hunt and bring food back to the 

 pups. One or more rendezvous sites are used after pups emerge from the den. These sites are in meadows or forest 

 openings near the den, but sometimes arc .several miles away. Adults will carry small pups to a rendezvous site. 

 Pups travel and hunt with the pack by September. The pack hunts throughout its territory until the following spring. 



Pack boundaries and territory sizes may vary from year to year. Similarly, a wolf pack may travel in its territory 

 differently from one year to the next because of changes in prey availability or distribution, intraspeciflc confiict 

 with nearest neighbors, or the establishment of a new neighboring pack. Because the attributes of each pack's 



