Caribou are a prominent species of deer inhabiting the vast northern landscapes of North America, Europe, and Asia. Known as reindeer in Eurasia, these animals are well-adapted to cold environments, ranging across Arctic tundra and boreal forests. Their impressive stature is a defining characteristic, marking them as one of the larger deer species.
Caribou Body Dimensions
Caribou exhibit considerable physical size, with typical standing shoulder heights ranging from 85 to 140 centimeters (2 feet 9 inches to 4 feet 7 inches). Their head-to-body length commonly spans between 120 and 220 centimeters (3 feet 11 inches to 7 feet 2 inches). An adult caribou’s weight can vary widely, generally falling within a range of 60 to 320 kilograms (132 to 705 pounds).
Adult male caribou, often called bulls, typically weigh between 159 and 182 kilograms (350 to 400 pounds). Some larger bulls have been recorded reaching weights of up to 318 kilograms (700 pounds). Female caribou, or cows, are generally smaller, with mature individuals averaging between 80 and 120 kilograms (175 to 265 pounds).
Variations in Caribou Size
Caribou size is not uniform across the species, showing notable variations influenced primarily by sex and subspecies. Males are consistently larger than females, with bulls of some subspecies weighing almost twice as much as cows.
Differences in body size are also evident among the various caribou subspecies. Woodland caribou are generally larger and possess a darker coat compared to barren-ground caribou. Adult male woodland caribou can weigh between 160 and 210 kilograms (350 to 460 pounds), with some reaching 272 kilograms. Barren-ground caribou males typically weigh less, between 100 and 150 kilograms (220 to 330 pounds). The largest known subspecies, Osborn’s caribou, can reach weights of up to 340 kilograms, while the Peary caribou is recognized as the smallest subspecies.
Antler Dimensions and Growth
A distinctive feature of caribou is that both males and females grow antlers, a characteristic unique among deer species. Bull caribou antlers can weigh up to 15 kilograms (33 pounds) and extend over a meter (3.3 feet) in length. Some record-setting barren-ground caribou have had left antler beams nearly five feet long. Female antlers are much shorter, typically measuring between 23 and 50 centimeters (9 to 20 inches) in length.
Caribou antlers undergo an annual cycle of growth and shedding. This growth is remarkably rapid, sometimes reaching up to 2.5 centimeters (1 inch) per day, making it one of the fastest growing tissues in the animal kingdom. During their development, antlers are covered in a soft, vascular skin known as velvet, which supplies nutrients. Male caribou typically shed their antlers in late fall or early winter after the rut, while females retain their antlers through the winter and shed them in May, often shortly after giving birth. The size and condition of antlers reflect an animal’s health, as their growth demands substantial energy and mineral resources, sometimes drawing calcium from the caribou’s skeleton.