Tuesday, October 15, 1996
About pack structure
Wolves, like people, live in families. This is pretty unusual. Not many mammals live in families. There are about 4,000 species of mammals and roughly 200 live in families. Families are beneficial because they allow wolves to defend a territory, care for and defend young, and hunt more effectively.
The wolf family or pack is always made up of an adult male and female wolf pair. They are called the alphas. If they have pups, the alpha female is the mother and the alpha male is the father. A pack can be just these two animals traveling and defending a territory together. This pair of wolves can have up to eight pups, but a litter is usually four or five pups. So a pair of wolves (the alpha male and female) with four young would be a pack of six wolves. When the pups are about one year old, they may leave the pack to find a mate and start a new pack. If some leave this will change the size of the family. Then the alpha female may have more pups in the spring. The pack would now consist of the alphas (mom and dad), the yearlings (pups from the first year), and the new pups.
The wolf pack that was just released last week the Soda Butte pack is a family like the one I just described. They have the alpha male and female which we call wolf numbers 13 and 14, one pup from last year (a female yearling called number 24), and two pups from this year. The news pups, one male and one female, are called numbers 43 and 44. This makes a pack of five.
The Rose Creek pack in Yellowstone also has a similar structure but is a different size. They have one alpha pair, six yearlings, and three pups for a total of 11. Another pack, the Leopold pack, has a more basic pack structure - two alphas and three pups. You can see that wolf families, like human families, vary a great deal.