The mating season is the most interesting period in a year of a wolf. The time for mating depends on the climate. When the wolves in the temperate zones mate already in winter the wolves in very cold regions wait until march, so that the cups will be born when the weather is warmer. Already months before the females become on heat, the first unrest begins to show. In the course of summer the females looked after the cups; it is a peaceful time. But now in the mating season especially the alpha-female become much more aggressive. All the other females on heat in the pack are attacked by the alpha-female. First they could save themselves with a playful behaviour and subservience. If the other females are her own daughters then the alpha-female lets them be, otherwise the attacks will continue as soon as there's a occasion.
Soon the other members of the pack join in, mostly the young ones. So the rivals are driven away or  are oppressed so strong that they won't approach a male at the end. The males are anyway only interested in the alpha-female. Now she exudes a special tempting smell. With a raised leg she begins to expose his urine everywhere. She snuggles up to the males, ask them to play with her and simply curries favour with them. That is what the males want; they walk always around the female and try to be in her nearness.
Only the alpha-male doesn't like that. He behaves menacing against the other males. If they get too close to the alpha-female, he jumps upon them and presses them down on the floor. Or he prevents, that they could come near at all. Normally the alpha-male get done to get his way. Gradually, he supplants the other males and follows the alpha-female first. He copulates with her, walks around with her and he never ever leaves her. The mating lasts up to 30 minutes. In the following eight to fourteen days the mating is repeated several times daily.(photo)
Before birth the mother digs a hole – often under a rock or a tree witch is fallen over. Sometimes she extends simply an abandoned fox's or badger's hole. The small entrance leads after three to ten metres into the roomy earth. Occasionally other females help her with extending the hole.
After a pregnancy of 63 days average the wolf gives birth between one to twelve, but often between four to six blind almost helpless cups. At the birth the young animals don't look like their parents: Their faces are round and dull, the hind legs are hardly developed and the short ears are firm on the head. The weight of the cups is almost one pound and their body length is about 20 cm. The cups have a short coat at birth. Usually it is brown and becomes lighter. Black wolves are already darker at birth than the lighter wolves. Their hair sometimes shimmers bluish.

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sources:
"Was ist was: Wölfe": Erik Zimen; copyright (c) 1997 by Tessloff Verlag
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