Life Cycle

Q. How long does a caribou live?
The mean lifespan is only 6 years, but their life expectancy is 13 years. These are very general numbers. Every animal faces its own set of situations that lead to a shorter or longer life. If a caribou lives in a herd that is declining (getting smaller over the years), it probably will have a shorter life than a caribou in a healthy or expanding herd. Also, many caribou die within the first year after they are born, and never reach adult age.

Q. How can you tell a caribou's age?
To get the most accurate age, a tooth can be pulled and examined in the laboratory. Under a microscope a stained slice of the tooth will show annual rings int the cementum which is similar to the growth rings of a tree. During captures, we also judge age of caribou based on tooth wear
(incisors).

Q.How do you determine an animal's age in the field?
The best features for determining age when viewing from a distance are the body size and characteristics and the antler growth.In the fall a calf will have velveted antler spikes between 4-10 inches. A yearling will have velveted antlers 10-18 inches and the neck mane will be very short. A two-year-old male will have a 20-26 inch antlers with a poorly developed brow (forward) tine and short heck mane. The two-year-old female is often seen with a calf at her heel. Older animals have larger antlers and males develop a long neck mane.

Q. How big is a caribou calf when it is born?
The calf, weighing 5-9 kg (11-20 lbs) at birth, follows its mother within an hour of its birth, and is capable of outrunning a human by the time it is a day old.

Q. What is the gestation period of a caribou?
Caribous have a gestation of 227-229 days, or about 7 and a half months.

Q. What do the calves eat?
The young nurse exclusively for about one month, then occasionally until winter comes.

Q.Can caribous have twins?
Twinning occasionally occurs in this species, but is not common.

Q. With so many caribou on the summer calving grounds, how can a mother keep track of her calf?
Caribou have a great sense of smell and are able to smell for their calf should it wander away. Sometimes the herd will stampeed to escape from relentless insect attacks and the calves are permanently separated from their mothers. When this happens the calf usually dies because it will be rejected by anyone but its mother.

Q. When do the caribou get their antlers?
Every year the caribou cast off and re-grow a new set of antlers. The annual cycle of antler growth, velvet, and antler shedding varies with gender, reproductve status and age. Mature bulls begin to grow antlers in early March. By August, antler growth is almost complete. The antlers of large bulls drop off after the Octover rut and most bulls are anterless by January. Pregnant cows carry antlers to calving time in late May or early June. Cows begin antler growth about one week after giving birth. Nonpregnant cows and yearlings shed their antlers in April or early May. A few nonpregnant cows carry their antlers into June.