The question of the “biggest bear” is complex because size can be defined by weight, height, or skull measurements. Reliable field measurements are historically rare, and many reported weights are estimates or come from captive animals, which skews the data compared to wild bears. We must consider the largest documented individual, the largest living species, and the largest species from the fossil record.
Identifying the Largest Individual Ever Recorded
The record for the largest documented bear individual belongs to a male Polar Bear (Ursus maritimus). This animal was reportedly shot in Kotzebue Sound, northwestern Alaska, in 1960. Its weight was reliably documented at 2,209 pounds (1,002 kilograms), significantly heavier than the average large male Polar Bear. When standing fully upright, this record-holder measured 11 feet 1 inch tall. For comparison, the largest recorded wild Kodiak Bear weighed 1,656 pounds (751 kilograms). Trophy records measure skull size rather than live weight, as skull size is a more consistent measure than body weight, which can fluctuate significantly between seasons.
Contenders for the Title of Largest Living Bear Species
The title of the largest living bear species is a close contest between the Polar Bear (Ursus maritimus) and the Alaskan Brown Bear (specifically the Kodiak subspecies). Male Polar Bears typically weigh between 660 and 1,760 pounds (300 to 800 kilograms) and are considered the largest living land carnivore by body mass. They possess a more elongated body, a longer neck, and a narrower skull, adaptations suited for their marine environment and seal-hunting lifestyle.
Kodiak Bears, isolated to the Kodiak Archipelago in Alaska, rival the Polar Bear in size and are the largest subspecies of brown bear. Mature males average between 1,052 and 1,177 pounds (477–534 kilograms) and can reach weights up to 1,500 pounds (680 kilograms) in the fall. Their immense size is partly due to island gigantism and a rich diet, particularly the high abundance of salmon in their coastal habitat.
While the Polar Bear generally holds the record for the largest single individual, Kodiak Bears can occasionally attain similar maximum masses. Kodiaks tend to be bulkier and stockier than the more streamlined Polar Bears. Ultimately, both species achieve their massive dimensions because of their hypercarnivorous diets and the thermal advantages of having a large body size in cold climates.
The Prehistoric Giant: Largest Extinct Bear
The fossil record points to the South American Giant Short-Faced Bear (Arctotherium angustidens) as the largest extinct bear. This species lived during the Pleistocene epoch, with an estimated weight that surpasses modern bears. Based on an analysis of its humerus, one exceptionally large individual was estimated to have weighed between 3,501 and 3,856 pounds (1,588 to 1,749 kilograms). This makes Arctotherium angustidens potentially the largest bear and one of the largest terrestrial carnivorous mammals known. Standing on its hind legs, this predator could have reached an estimated height of 11.2 to 14.1 feet (3.4 to 4.3 meters). Its North American cousin, the Giant Short-Faced Bear (Arctodus simus), was also massive but likely smaller than the South American record-holder.