Is there any real difference between the grizzly bear and the Alaskan (Kodiak) Brown Bear?

Question

I believe I have read that the Alaskan Bear is larger. Is this true? Are they simply the same species of bear living in a different regions (interior vs West Coast)? Or are there any genetic differences between the two?

Answer 1

You read/heard right. The Kodiak bear and the Polar bear are the largest members of the bear family.

They are both subspecies of Brown Bear. But the Kodiak bear occupies the islands of the Kodiak Archipelago in southcentral Alaska. While the Grizzly lives in the uplands of western North America.

Brown bears found inland and in mountainous habitats are called "grizzlies" while brown bears living in coastal areas are called coastal brown bears. The Kodiak brown bear is isolated to Kodiak Island in Alaska.

In comparison, the grizzly is considerably smaller than  the Kodiak brown bear. This size difference is due to the abundance of food available in coastal areas and on Kodiak Island. The bone structure of the Kodiak is much larger than other brown bears.

Answer 2

Same species.  The Kodiak population is a closed one.  That's why the color remains.  But they can breed and have young with a grizzly.

Answer 3

I lived on Kodiak Island for six years and several years in Sitka - both have large brown bear populations.  

The Kodiak bears feed on salmon as much as possilbe - and there is salmon comming up all sorts of streams, all over the place.  Over the years this has made them larger than the other coastal Alaskan brown bears, and the interior brown bears.  

Because Kodiak receives the tail end of the Japanese warm current the Island does not get the bone chilling cold associated with the rest of Alaska.  Although many of the bears hibernate..... for some it's only a few weeks and still some have been known to not den up at all.  This makes the bears of Kodiak extremely unique.

Hope this helps!

Answer 4

All Brown bears come under the scientific classification URSUS ARCTOS. There are 10 sub-species of which the Kodiak and the Grizzly are two members. The Kodiak is classified URSUS ARCTOS MIDDENDORFFI. The Grizzly is classified URSUS ARCTOS HORRIBILIS. There are both genetic and physical differences. Even amongst the grizzly population itself there are differences. Inland grizzlies are considerably smaller than their coastal counterparts due to a variation in diet and a shorter foraging period. Those in the Yukon region vary also in appearance from other Grizzlies and can be near-black through to light brown/yellow. Note that coastal grizzlies including those along the Alaskan west coast are not to be confused with a small population of brown bears found on the Alaskan peninsula and other brown bear populations along the Alaskan coast which are genetically very similar to the Kodiak brown bear and are classed URSUS ARCTOS GYAS. Grizzlies actively breed with this coastal variant and there is ongoing debate as to whether they should be classed as a separate sub-species at all.  The main difference between Kodiaks and ALL Grizzlies is that from which they get their name. As grizzlies mature, their hair tips become grey-silver giving them a 'grizzled' appearance - hence the name. This is a genetic trait shown only in this sub-species. The Kodiak brown bear is found exclusively on the Alaskan archipelago (including Kodiak, Afognak amongst others). They are by far the largest of all the brown bears due in part to their nutrient-rich intensive salmon diet. Their isolation for at least 10000 years coupled to a unique protein rich diet has lead to genetic differences from other brown bears. FOOTNOTE - It was originally thought (and is current thinking also) that the Polar Bear diverged from the brown bear family some 200,000 years ago. Very recent debate and study may prove otherwise. It MAY BE that the Polar is in fact a white variant of the brown bear as modern electrophoresis (DNA analysis) and the fact that Polar/Brown hybrid offspring are fertile points towards this latest thinking . HOWEVER IT IS MUCH TOO EARLY TO STAKE THIS CLAIM !!!