Adults tigers, no way. Cubs, yes. As for bears, it's hard to imagine even a black bear not being able to kill a wild boar. And an adult grizzly would be no match. An adult wild boar weighs 100 - 200 lbs. Adult tiger weighs between 400 to 600 lbs. An American black bear, about 240 lbs. Adult grizzly 600 - 800 lbs. read more
But in the U.S. now, there’s a bigger problem with feral pigs which are domestic pigs which have been able to survive, prosper and expand their range over many states such that they are also hunted but often are killed as a pest. read more
Both domestic pigs and wild pigs can kill a human rather easily. A dometic pig could kill a human being just by being big. If someone were to accidently get in their way, the pig could easily crush them. Smaller Pot-bellied pigs could also kill if they were to knock someone down and stomp on them I suppose. read more