Previous classifications of
Rangifer tarandus, either with prevailing taxonomy on subspecies, designations based on ecotypes, or natural population groupings, failed to capture "the variability of caribou across their range in Canada" needed for effective species conservation and management. "Across the range of a species, individuals may display considerable morphological, genetic, and behavioral variability reflective of both plasticity and adaptation to local environments." COSEWIC developed Designated Unit (DU) attribution to add to classifications already in use. The recent revision By 1949, when
Rudolph M. Anderson published the first compendium of Canadian mammals (Anderson knew caribou: he had led biological expeditions from Point Barrow, Alaska to the
Coronation Gulf in 1908-1912 and 1913-1916 and was then Chief of the Biology Division of the Canadian Natural History Museum), the woodland caribou was one of just four recognized species: Arctic caribou (
R. arcticus), Peary caribou (
R. pearyi), Ungava caribou (
R. caboti), and Woodland caribou (
R. caribou). Anderson left the Newfoundland caribou as a subspecies of woodland caribou,
R. caribou terranovae. By mid-century, the taxonomic pendulum was swinging the other way. Ellerman and Morrison-Scott had brought all reindeer and caribou in the world under one species,
Rangifer tarandus. In 1961,
A. W. F. "Frank" Banfield, who had succeeded Anderson as Chief of the CMNH Biology Division, published a revision of the genus
Rangifer that was widely rejected by other caribou specialists. He reduced the number of living subspecies in Canada to two, renaming barren-ground caribou as
R. t. groenlandicus and woodland caribou as
R. t. caribou. McTaggart-Cowan published a scathing review. Most other mammalogists accepted Banfield's classification for the species,
R. tarandus, but continued to recognize the subspecies Labrador (Ungava) caribou (
R. t. caboti), barren-ground caribou (
R. t. groenlandicus), Newfoundland caribou (
R. t. terranovae), Peary caribou (
R. t. pearyi), and Osborn's caribou (
R. t. osborni). A recent revision In eastern North America caribou are classified into three ecotypes – "the mountain caribou which is found south of the
St. Lawrence River, the barren-ground caribou which calves in the tundra, and in between, the forest-dwelling ecotype which lives all year long in the boreal forest. In west-central Alberta there are two ecotypes – boreal and mountain. In Québec there are three ecotypes with specific habitats and behavior – migratory barren-ground ecotype, the mountain ecotype and the forest-dwelling ecotype (boreal woodland caribou). In British Columbia caribou are classified into three ecotypes – Mountain, Northern, and Boreal. In Ontario caribou are classified into two ecotypes – forest-dwelling woodland caribou and
forest-tundra woodland caribou. In Newfoundland and Labrador, woodland caribou are classified as part of the boreal population of caribou, which is subdivided into two ecotypes: the migratory forest-tundra and the sedentary forest-dwelling. In the Northwest Territories, the
Canadian Parks and Wilderness Society identified five types of caribou – boreal woodland caribou, northern mountain woodland caribou, barren-ground caribou,
Peary caribou and the Dolphin-Union caribou herd. "The Boreal woodland caribou live in the forests east of the
Mackenzie Mountains and tend to live in small groups. They prefer to stay within the forest for most of the year and do not migrate." == Range and population changes ==