Study the wolf population data since reintroducing the wolf back to the park. Table 1 - Number of wolves and number of packs at the end of each year* 1995 1996 1997 1998 1999 2000 200 2002 2003 2004 2005 # Wolves 21 51 86 112 118 119 132 148 174 171 118 # Packs 3 9 7 11 11 8 10 14 13-14 16 13 2006 2007 2008 2009 2010 2011 # Wolves 136 171 124 96 97 98 # Packs 13 11 12 14 11 10 1995-1999 data represents Greater Yellowstone Area (GYA); 2000-2011 data is specific to Yellowstone National Park. Table 2 - Predominant prey species * Table 3 - Livestock predation* Species 2011 Wolf Kills Cows Dogs Goats Sheep Foal Elk 78% 1997 6 0 0 68 0 Bison 4% 1998 3 1 0 0 0 Deer 5% 1999 4 6 0 13 1 Moose