From animal experimentation to factory farming, humans have done some horrible things to other animals. Few practices are as cruel, though, as bear bile farming.

The practice is so barbaric that bears kept in captivity for bile harvesting are often driven mad by the poor living conditions and cruelty of the process. Now reports have surfaced that some bile bears may be performing hunger strikes and committing suicide as a last respite to protest the cruel conditions they're kept under, according to Wildlife Extra.

Consider wildlife campaigner Louis Ng's visit to a Laotian bile farm in 2009. There he encountered a female bear lying motionless in a cage. The owner of the farm explained to Ng that the bear was refusing food and was starving herself to death. This kind of behavior was not uncommon, he explained. This bear was on the 10th day of her "hunger strike" and had been left outside, likely dry of bile, to meet her inevitable end.

After a few minutes sitting with the bear and mourning her fleeting life, Ng watched as her paw limply reached out from a hole in the cage toward his hand, as if she wanted to hold it. Filled with emotion, Ng gave it to her. They sat there, hand in paw, for several minutes. Ng described her eyes as filled with both anguish and gentleness. It was a moment he would never forget.

The bear succumbed the following day.

Tragically, this bear's story is just one of many. Around 12,000 bears are currently estimated to populate bile farms across Southeast Asia. It's all done in the name of traditional Chinese medicine, for which bear bile is believed to be an essential ingredient.

The typical bile farm holds its bears in extraction cages — sometimes called "crush cages" — which measure about 2.6 feet by 4.2 feet by 6.5 feet. For animals as large as Asiatic black bears, the species most often harvested for bile, these dimensions can make it impossible to stand up or even roll over. The lack of movement is convenient for farmers, since it allows them easier access to the bear's abdomen, where the bile can be extracted.

"The bile is removed from the bear by inserting a catheter tube through a permanent incision in the abdomen and gall bladder," explained Ng. "Sometimes a permanently implanted metal tube is used."

Needless to say, the process is extremely painful for the bears. Bile is typically tubed from the gall bladder at least twice a day. Often the solitude, pain and fear will drive bears to madness. According to Ng, the dominant sound inside a bile farm is a banging noise — bears slamming their own heads against the cages.

Other bears have been known to chew off their own limbs. One incident in China saw a mother bear escape from her cage, run over and strangle her cub to death, then kill herself by intentionally running into a wall.

These tragedies are difficult to hear, but for some people they may raise further questions. For instance, is it really possible that these animals are capable of consciously and purposely killing themselves, as Ng's encounter might suggest? Might they even be doing it as an act of protest?

Scientists warn of anthropomorphizing animal behavior, but such attributions do have comparisons elsewhere in the animal kingdom. For instance, whales are known to beach themselves, and a few scientists have postulated that some of these beachings demonstrate suicidal behavior. Stories also abound of dogs and horses killing themselves to escape maltreatment. Ric O'Barry, former dolphin trainer and current animal activist, has claimed to have witnessed a depressed, captive dolphin named Kathy willingly commit suicide in his arms.

Although no one can say for sure what goes on inside another animal's head, these tragedies resonate. Regardless of whether the bear suicides were intended as protest or not, they are waking people up to the horror of bile farming.

For instance, Ng is currently setting up a five-hectare bear rescue center in Laos. Not only will the bears be rescued, but they will also be put through a rehabilitation process that will help adapt them to a community — something they've never experienced on the bile farms.

It's just a first step, but for all the bears who have never stepped foot outside of a crush cage, it's a big one.