Wolves mate when a male wolf mounts a female wolf, or bitch, from behind during the female's estrus, which is the period of time when she is in heat. This period, which lasts from four to seven days, is signaled when the female lifts her tail in a particular way.
The mating process, however, really begins with the meeting and bonding stage, according to the Wolf Howl Organization. Once two wolves meet and establish a non-threatening relationship, usually by sitting shoulder to shoulder, they bond through playing, grooming and nuzzling. Courtship is a more intense version of bonding, with playful mounting behavior. Copulating then occurs. If copulation results in a pregnancy, the female carries her young for 63 days and then gives birth to a litter of four to six pups.
Usually only the alpha male and beta female in the pack mate, and they only have one litter per year. In this way, the young do not overextend the resources of the pack. In some cases, young females may also breed. Wolves reach sexual maturity between ages 2 and 3 years, at which point they leave their pack to either find a new pack to join or to create one of their own. Wolves mate for life.