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Question Which is the largest bear species on earth?


If we are specifically focusing on species, the clear winner is the polar bear. However, if we include the Kodiak bear, a subspecies of brown bear,  then it is a draw.

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

Answering which bear is the largest is fraught with conflict. How does one define largest? By average weight, height, and length, or heaviest recorded? Many sources say the polar bear is the clear winner, but others say the Kodiak bear, a subspecies of the brown bear, is largest. It is best to call it a draw, which is the position taken by Gary Brown in The Bear Almanac (2009)

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.
Chart figures are from The Bear Almanac by Gary Brown (2009).


Polar Bear

Kodiak Bear

Average weight

1150 lbs. (1993 edition)

787 lbs. *average of coastal brown bear

Weight range

900-1500 lbs. (1993 edition)

500-900 lbs. (1993 edition)

Heaviest recorded

2210 lbs.

2500+ lbs.

Average height

Up to 5.3 ft

3-5 ft. *average based on brown bears overall

Average length

8-8.4 ft.

5-10 ft.

In the chart above, the brown bear figures are based on the species overall, rather than just the Kodiak subspecies. Gary Brown’s The Bear Almanac compares coastal and inland brown bears, putting the coastal bears (which includes the Kodiak subspecies) at an average of 787 lbs., and inland bears at an average of 319 lbs., so it is apparent that there is a much wider range for all of brown bears, as opposed to what it would be if it were just the Kodiak subspecies. Add to that the difference in build between Kodiak bears and polar bears, and comparisons become a bit tricky. Polar bears are lanky, with long faces and necks, whereas the Kodiak bear has a flat face and a dense build.

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

Seasonal variation also makes comparisons difficult. Sylvia Dolson notes in Bear-ology (2009) that some bears weigh almost twice as much in the fall as they would in spring.  If you’ve ever followed Fat Bear Week by the National Park Service, you’ll know that terrestrial bears work hard to pack on the pounds before hibernation. According to Bill Sherwonit in Alaska’s Bears (2016), male brown bears generally range from 500-900 lbs., but some coastal “giants” get to 1,500 lbs.  or more in the fall. Kodiak bears are said to be able to grow extremely large due to the abundance of salmon available in their habitat. Converse to that, the weight of polar bears could be on a downward trend, due to habitat loss which impacts their hunting and food supply.

No matter how you look at it, both polar and Kodiak are really large bears!

Published: 07/29/2023. Author: Science Reference Section, Library of Congress

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