This subspecies of caribou is endemic to the Canadian Arctic Archipelago, living on the edge of plant growth in polar desert and arctic tundra environments. The current population is estimated at 13,200 mature individuals. From a population high of 22,000 in 1987, the species experienced a catastrophic die-off in the mid-1990s related to severe icing events in some parts of its range. The population was ca. 5,400 mature individuals in 1996, the lowest since surveys first commenced in 1961. Of four subpopulations, two are currently showing an increasing trend, one is stable, and the fourth has fewer than 10 individuals at the last count in 2005, with no evidence of any recovery. The overall population has experienced an estimated three-generation decline of 35%, but has been increasing over the past two decades. The highest-impact threats derive from a changing climate, including increased intensity and frequency of rain-on-snow events negatively affecting forage accessibility in winter, and decreased extent and thickness of sea ice causing shifts in migration and movement patterns. The original designation considered a single unit that included Peary caribou, Rangifer tarandus pearyi, and what is now known as the Dolphin and Union caribou, Rangifer tarandus groenlandicus. It was assigned a status of Threatened in April 1979. Split to allow designation of three separate populations in 1991: Banks Island (Endangered), High Arctic (Endangered), and Low Arctic (Threatened) populations. In May 2004, all three population designations were de-activated, and Peary caribou was assessed separately from Dolphin and Union caribou. The subspecies pearyi is composed of a portion of the former 'Low Arctic Population' and all of the former 'High Arctic' and 'Banks Island' populations, and it was designated Endangered in May 2004. Status re-examined and designated Threatened in November 2015.