It’s possible that as many as two hundred thousand gray wolves once thrived across the United States. But human settlements expanded and the species was viewed as a threat to livestock, and wolves were gradually eliminated from most of their original territory.

But in 1995, the U.S. Fish and Wildlife service began a bold movement to capture wild wolves in Canada and reintroduce this formidable predator back into the backcountry of Yellowstone National Park.

Although winter in Yellowstone is a harsh season, wolves remain active. They have two layers of hair – course on the outer and a silky layer closest to their skin – that help them stay warm on even the chilliest, snowiest days.

Wolves live, travel, hunt and raise young in organized groups called packs. A dominant pair – an alpha male and female – are the primary breeders and lead the unit. They will move up to a hundred miles per day in search of prey or territory.

Rarely does a person observe the complexities of a wolf pack from the inside, but naturalist Casey Anderson tracked the silver pack in Yellowstone’s backcountry to learn more about this fascinating species…..

Fast Facts
Height: 26-32 inches (.7-.8m) at the shoulder.
Length: 4.5-6.5 feet (1.4-2m) from nose to tip of tail.
Weight: 55-130 lbs (25-59 kg); Males are typically heavier and taller than the females.

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