You are in their house without an invite.

Instinct.

We are unwelcome in their turf!

They don't like the fact that their habitat is getting smaller and smaller. The Indians had their arrows to defend their territory and the wild animals have their teeth.....

Wild animals are not always "pissed off". They only seem so when we get too near them because they feel threatened by us.

Same reason people always are... Because half of us are complete idiots that piss off the other half.

Their territories are shrinking so fast! the destruction caused by humans could be the major reason why.

Because we human are always F&%$#@! with them!

Because they think you are going to kill or capture them or their offspring. They are right to feel this way.

Why do you say they're always pissed off?

Because us humans have been moving into their territory for well over two centurys at a rapid rate of speed, driving them to the brink of nothing with no hope of return. That would tend to piss me off, nooooo doubt.

The ones around here aren't...the deer hang out around the salt lick in the backyard, the racoons would come in the house for cat food if I would let them, there's a red fox that hangs out in my yard...but I do wish the coyotes weren't so comfortable around here...I don't see them as angry but I do worry about my cats.

Raw meat only... That THEY have to find and kill... (Unless they're not meat-eaters, then they still have to find it!) No soapy baths, pedicures, pampering... Jealousy of domesticated animals... Name it! ;-)

Jealousy!!! They know they arent as cute, clean, cuddly and loved as our house pets! haha

That's what makes them wild, untamed and guided by pure killer instinct! Even rabbits...beware, those things go psycho, should you actually manage to corner one.

Its the grass : ) Mating season, because they might be happier if it was year round.

They aren't. Only when they feel threatened.

Reading this question made me laugh:) Anyways, I guess it casue they only know survival?

I have never seen a pissed off sloth

It's not that their always "pissed off" it's just their natural instinct just like when us people get in uncomfortable and unusual situations we feel awkward and such that's how the animals are.

The can't find a job, they need to hunt for food, we are lucky, we can just go and buy it at the store.

theyre not. wild animals usually only get pissed off when we invade/encroach on their territory, come near their young, feel cornered/threatened or are rabid. i think some wild animals have had bad experiences with humans, and they carry that memory with them. but most wild animals are either afraid of us, mildly curious or only interested in the foods we may be carrying with us. in some cases larger predators like grizzlies might be licking their chops thinking about the yummy taste treat in front of them, but thats the exception, not the norm. animals only seem pissed off all the time because of bad journalism ~ networks like fox tv love pumping out all that when animals attack caca. its the typical fear-based television that scores huge ratings. i also think theres also a machiavellian element to it ~ big corporations that run the networks are usually anti-environment. wild animals just get in the way of smooth business operations. so why not portray wild animals as the bad guys, let the public turn against them, so they can conduct their hassle-free business, rape the land and steamroll over what little wildlife that remains to maximize profits?