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Question Which is the largest bear species on earth?


The polar bear.

Large Polar Bear, Alaska.  Mike Lockhart, photographer, 2009.  USGS Science Explorer.

It is a close call, but the polar bear is generally considered the largest bear species on Earth. A close second is the brown bear, specifically the Kodiak bear. The Kodiak is a subspecies of the brown bear native to Alaska.

Playful wrestling between two Kodiak brown bears (Ursus arctos middendorff), Kodiak National Wildlife Refuge.  Steve Hillebrand, USFWS photographer, 2014.  U.S. Fish and Wildlife Service National Digital Library.

The consensus among experts is that the polar bear is the largest, but some believe the Kodiak bear to be larger. Part of the dissension comes from the vagueness of the word “largest.” The answer really depends on how “largest” is defined – Heaviest? Longest? Largest ever recorded?

Polar Bear walks across flooded barrier island during Arctic storm.  Cordell Johnson,  USGS Pacific Coastal and Marine Science Center photographer,  2016.  USGS Science Explorer.

The following data, taken from Gary Brown’s Great Bear Almanac (New York, 1993), compares the average measurements of the polar and brown bear.

Polar BearBrown Bear
Average Weight of Mature Male900-1,500 pounds500-900 pounds
Heaviest Recorded2,210 pounds2,500+ pounds
Average Length of Mature Male8-8.4 feet>7-10 feet

Source: The Great Bear Almanac by Gary Brown

Published: 11/19/2019. Author: Science Reference Section, Library of Congress

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