Wolf Pup Neonatal Period
(from birth to 12 - 14 days, when eyes open) Birth: Born approximately one pound, blind, deaf, darkly furred, small ears, rounded heads, and little if any sense of smell. They are unable to control own body temperature. Their motor capacities are limited to a slow crawl and to sucking and licking. They possess a good sense of balance, taste and touch. Nursing pups feed four or five times a day for periods of three to five minutes. On average, females will gain 2.6 lbs. and males 3.3 lbs. per week for the next fourteen weeks. This time is known as the "period of maximal growth."
Wolf Pup Transition Period
(eye opening until about 20 - 24 days) 2 weeks: Eyes open and are blue at 11-15 days, but vision is poor. They can start eating small pieces of meat regurgitated by adults. Pups begin to stand, walk, growl and chew.
Wolf Pup Socialization Period
(20 - 24 days until about 77 days) 3 weeks: Begin appearing outside the den and romping and playing near the entrance; hearing begins (~27 days, ears begin to raise; ~31 days, ears erect but with tips still flopping); canines and premolar teeth present. 4 weeks: Weigh 5-6 lbs.; grow adult hair around nose and eyes; bodies begin to take on conformation of adults with disproportionately large feet and head; high-pitched howls are gaining strength; mother may go off for hours on end to hunt; dominance and play fighting begin. 5 weeks:Gradual process of weaning begins. Can follow adults up to one mile from den. 8 weeks: Disproportionately large feet and head. 8-10 weeks: Adults abandon den and move pups to rendezvous site; weaning complete, pups can feed on food provided by adults; adult hair becomes apparent on body. 8-16 weeks: Eyes gradually change from blue to yellow-gold.
Wolf Juvenile Period
(12 weeks to sexual maturity) 12 weeks: Begin to accompany adults on hunting trips and return to rendezvous site by themselves. 3.5 months: Pups will gain approximately 1.3 lbs. per week for the next three months. 4-6 months: Milk teeth replaced; winter pelage becomes apparent. 6 months: Pups begin to accompany adults on hunts; pup appearance nearly indistinguishable from adults. 7 months: The "period of slow growth (27-51 weeks)" begins: the female pups will gain approximately .07 lbs. per week and the male pups will gain approximately .4 lbs. per week; pups begin to travel with pack. 7-8 months: Actively begin hunting. 1 year: Epiphyseal cartilage closes off, marking the end of skeletal growth. 22 months: Sexual maturity. Mech, Dr. L. David and Boitani, Luigi eds. (2003) Wolves: Behavior, Ecology, and Conservation. University of Chicago Press: Chicago. Mech, Dr. L. David. (1970) The Wolf: The Ecology and Behavior of an Endangered Species. University of Minnesota Press: Minneapolis, p. 136, 140-143.
Courtesy of the International Wolf Center