One of the big stars of Geographic was a big, heavily scarred male that we called “Al” (as in Al Pacino - Scarface). He appeared to be the dominant bear, as all other bruins in the area gave him wide berth. While we never saw any bears fighting at Geographic, the evidence of some serious combat was obvious.
On one of our last days in Katmai, we observed a large boar with a flap of flesh peeled back from a large, open wound on its hind quarters. Every adult boar had war wounds. In most cases, these were gashed on the forelegs or wounds around the neck area. One bear had a gash on its head that almost reached the eye (at first we thought the eye had been damaged). While everything seemed fairly copasetic during our stay, the area was no doubt an arena from some terrific bruin battles.
A large boar bearing wounds on the forelegs and around the neck - war wounds from intense bruin battling!
Grizzly Aggression
Stonorov and Stokes (1972) found that there were four situations in which aggression most often occurs in brown bear aggregations. They were: 1. when one bear moves too close to another bear (invades personal space) 2. when one bear loses a challenge but then redirects its aggression toward a nearby bear (displacement aggression) 3. when two bears compete for a preferred fishing site 4. when two strange bears meet.
Stonorov and Stokes describes what happen during an intense, aggressive encounter between two bears that are similar in social ranking. The first thing that occurs is the bears confront one another – the two brown bears face each other with the front legs stiffened, the heads are lowered slightly and the movements occur in slow motion, the ears are laid back, both have their mouths wide open (this exposes the canines) and there is excess saliva production.
One of two things may happen at this point – one of the bears may back down or one or both bears may charge one another. When charging occurs one or both bears run at each other, the head is lowered and the ears are back and the mouth is open slightly. If neither bear breaks off the charge and retreats at this point, the big bears will come to blows. The bruins may swipe at each other with their fore paws, bite each other (usually on the neck) or lock jaws.
When one bear has had enough, it will drop its head even lower than its opponent and begin to slowly back away. At some point, the subordinate may walk or run away. During much of the encounter, there will be lots of vocalizations.
References:
Stonorov D. and A. W. Stokes. 1972. Social behavior of the Alaska brown bear. Int. Assoc Bear Res. & Mang. 23: 232-242.
© Scott W. Michael