CHAFIEK 2: AFFEnEO KNVIRO.NMKNT 



was 185 mi" (8 packs). Individual territories were highly variable in size, with a range of 24-614 mi^ 

 (USFWS et al. 2000). 



Territories in the GYA were larger, averaging 344 mi" (1 1 packs). Individual pack territories ranged from 

 33 to 934 mi". Central Idaho wolf packs had the largest average territory size of 360 mi" (13 packs), with 

 individual pack territories ranging from 141 - 703 mi" (USFWS et al. 2000). 



Dispersal. When wolves reach sexual maturity, some remain with their natal pack while others leave, 

 looking for a mate to start a new pack of their own. These individual wolves are called "dispersers." 

 Dispersal may be to nearby unoccupied habitat near their natal pack's territory or it may entail traveling 

 several hundred miles before locating vacant habitat, a mate, or joining another pack. It appears that 

 dispersing wolves utilize scent-marking behavior and howling to locate other wolves, and frequently use 

 similar travel paths used by previous dispersers. In this regard, habitats occupied by wolves sometime in 

 the past will likely be occupied by wolves in the future, as long as the prey base remains adequate. 



Boyd and Pletscher (1999) indicated that the dispersers in their study moved toward areas with higher 

 wolf densities than found in their natal areas - in this case north toward Canada. This has important 

 implications for Montana wolves because there are now resident wolf packs to the south and west in 

 central Idaho and YNP. Dispersal has already resulted in the formation of several new packs in Montana 

 between those core populations (Fig. 2) (Boyd et al. 1995, USFWS et al. 2001). Wolves will probably 

 continue dispersing from the core areas and slowly occupy landscapes between the Canadian border, 

 central Idaho and northwestern Wyoming (USFWS et al. 2000). Ultimately, this will yield a larger 

 regional population, capable of genetic exchange across the international border and northern Rocky 

 Mountains (Forbes and Boyd 1996, 1997). 



Boyd and Pletscher (1999) studied wolf recovery in northwestern Montana from 1979 to 1997. Male 

 wolves dispersed at an average age of 28.7 months and traveled an average of 70 mi from their natal 

 territory before establishing a new territory or joining an existing pack. Females averaged 38.4 months 

 old at dispersal and traveled an average of 48 mi. Males and females, combined, traveled an average of 

 60 mi (range 10 -158 mi). There were two peaks of dispersal: January-February (courtship and breeding 

 season) and May-June. 



Increasingly, dispersal is being documented among and between all three recovery areas in the northern 

 Rockies (Bangs et al. 1998, Mack and Laudon 1998, Smith et al. 2000). Combined, there were 21 known 

 dispersal events in 2000 and 19 in 1999 (USFWS et al. 2000). Dispersal paths crossed international 

 boundaries, state boundaries, public and private land boundaries, different land uses, and agency 

 jurisdictions. 



Mortality. Wolves die from a variety of causes, usually classified as either natural or human-caused. 

 Naturally caused mortalities result from territorial conflicts between packs, injuries while hunting prey, 

 old age, disease, starvation, or accidents. In an established Alaskan wolf population largely protected 

 from human-caused mortality, most wolves were killed by other wolves-usually from neighboring packs 

 (Mech et al. 1998). However, in the northern Rockies, natural mortality probably does not regulate 

 populations (USFWS 2000). Humans are the largest cause of wolf mortality and the only cause that can 

 significantly affect populations at recovery levels (USFWS 2000). Human-caused mortality includes 

 control actions to resolve conflicts, legal and illegal killings, as well as car/train collisions. 



Genetics. In recent years, the application of genetic techniques to the study of wildlife populations has 

 permitted managers to address issues of genetic diversity and population viability with increased 

 confidence. These techniques have yielded information relevant to wolf conservation and management in 

 the northern Rockies. Wolf recovery in the northern Rockies advanced from the combination of 



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