ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)

[Wolverine]

(12-16-2018, 04:00 PM)peter Wrote: I was a bit surprised to read that no clear evidence of male brown bears displacing male tigers was found in the Sichote-Alin reserve in the period 1992-2013. This although male brown bears (referring to the table posted by Guate) really average very close to 600 pounds.

I think you are right that such a behavior - occurrence of "satellite" bear following persistently a particular tiger is not something common in Ussuri forest, probably even quite rear, also Sihote Alin state reserve is home of only 10-15 tigers hence only 3% of all Amur tigers, while 97% of Amur tigers inhabit outside this reserve. When that old hunter (by the way he mention that has 50 years of experience in hunting) describes the bear-tiger displacement he talks as a outstanding event, not something you can observe every year, probably this is the only such a case in his long career, otherwise he is not going to tell the story to journalists. In same way when last year gigantic brown bear was following and displacing almost a month the tigress Rachel with 2 subadult cubs biologist Alexander Batalov also described this case as event, as a news, obviously its not something happens regularly.

The brain of brown bears is sofisticated, every bear is different. In order one bear to confront and displace a tiger/tigress it needs not only to be a big one but needs also to be enough brave. Some bears are quite shy and coward while others are brave. Far not every bear will dare to confront such a fierce animal as tiger/tigress. Also we have to make difference between persistent scavenging and accidental scavenging when a bear unexpectedly runs into tiger kill and displace the cat. Obviosly accidental scavenging should be more common than persistent scavenging. 

What is common between the case described by the old hunter Victor and the case described last year by Batalov. They both occurred late autumn - October-November, both bears were exceptionaly big and obviously needed to gain enough fat and weight before entering into hibernation. 

To remind the photos from camera trap last autumn when huge (probably 400 kg) brown bear was following and displacing almost a month a tigress with 2 subadult cubs. The photos were made with only 30 minutes time difference:

*This image is copyright of its original author

*This image is copyright of its original author

How often occure such a displacements in Ussuri forest - we don't know exactly. Probably not very often. Its possible that a professional hunter in RFE observe such an event only once or twice in his entire career.

Here we have to remind how often were observed grizzly bears following and scavenging on wolf packs in North America, because bear-wolf interactions are better studied. Reply