Alaska conservationists determined to revive wood bison herds

For centuries, the Athabascan people of Alaska relied on wood bison for survival. That is until the species, deemed by the National Park Service as the largest terrestrial animal in North America, disappeared in the early 1900s. 

So when a small herd of wood bison was discovered in a remote section of northern Canada in 1957, a reintroduction program was born to protect the animals from extinction. 

"It's just really cool to be in the presence of a bison," Sarah Howard, executive director of the Alaska Wildlife Conservation Center, told CBS News correspondent Jeff Glor.