Amur Tigers

[peter]

(04-27-2014, 09:27 AM)'GuateGojira' Wrote: Great information Apollo, it seems that the Amur tiger prey selection is biased toward the adult specimens. Although in second place are the young animals, the problem with this tiger population is that a small animal will not provide too much food and taking in count the very low prey density, they prefer the larger prey possible as they don't know when they will be able to eat again, definitely it is a hard life.

So, the Amur tiger (Av. 190 kg ♂, 120 kg ♀) prefer the adult red deer (Av. 224 kg ♂, 149 kg ♀) and the adult wild boar (Av. 193 kg ♂, 92 kg ♀); the relation predator/prey is between 1/0.5 - 1/2.
 


 

It could be they concentrate on adult deer and wild boar in summer, but in winter Amur tigers, according to Yudakov and Nikolaev (1970-1973), target young animals in particular. The reason is snow. The average snow depth in Sichote-Alin is about 38 cm. This means animals tire very quickly when they move. Young animals in particular sometimes perish from exhaustion, whereas others are unable to get away when they are confronted by tigers. Tigers, when they travel through snow, often rest. Same when they hunt. This strategy, a result of conditions and adaptation, pays. Male tigers in particular seldom completely eat the animals they kill, Yudakov and Nikolaev found. In most cases, they eat between 25-50%. They very seldom return to kills as well. Meaning they do well in winter, in spite of the snow. 

This was the situation in the early seventies of the last century. In the late nineties and at the turn of the century, the situation had changed. There were much more tigers, but hardly tigresses with cubs. The reason was different conditions, humans and much less ungulates to hunt. Tigers starved. After the collapse of the Sovjet-Union, millions lost their jobs when state firms closed down and banks fell over. In Sichote-Alin, many entered the forest in order to eat. They had to. The result was less ungulates and hungry tigers. This is why they entered villages to hunt dogs and why they changed their behaviour towards humans. 

Different conditions and shortages could also be related to tigers and bears. Yudakov and Nikolaev found only one female black bear and a cub killed by one male tiger. That was it. At the turn of the century, however, some male tigers had turned into specialists, just like in the forties and fifties of the last century and for similar reasons. They hunted bears because they had to. Bears replaced wild boar and deer. Male bears, very probably, acted in a similar way. Some (satellite bears) followed tigresses with cubs and immature tigers and at times hunted and killed them for food. This is what authorities think and I think they could be right.

The conclusion I got to after reading Yudakov and Nikolaev is tigers are not much different from us. They like to take things easy when the situation is favourable. They don't mind hunting piglets at all, as long as there are enough. In hard times, they change because they have to. Any tiger going for a bear probably starts at the bottom. When things go well and they get more confidence, they might try immatures and females. But going for adult males doesn't seem likely. Any tiger, specialist or not, who goes for a bear of similar size, black or brown, is taking a chance and they know. My guess is tigers learn to hunt bears when they, in difficult times, are confronted with the results of what bears do for a living. When they had enough, chances are they will engage a bear. The outcome is unpredictable, but there is enough circumstantial proof that tigers who learned how to hunt bears will confront animals of similar size or better at times. But that's another discussion. Reply