When Alejandro first approached me about appearing in "The Revenant," I was overjoyed. I don't have to tell you that the number of good parts for bears in Hollywood is inexcusably small—it's almost as hard as being a female actor over forty. And what Alejandro was offering was gold: a guaranteed appearance in the trailer, closeups, even a few lines of dialogue. I'm no fool. I signed on the dotted line (by clawing at the paper and urinating all over it).

This was my first film with Alejandro, but I knew him socially. We got burritos together once. He is godfather to one of my children (three of whom have non-speaking cameos in the film). Though I realized that making a movie in which a man is horribly mauled by a bear might be an intense experience, I had no reason to doubt it would be meaningful. As filming drew near I was the envy of all my bear friends, who bit me affectionately and told me that I would bring home a treasure trove of anecdotes.

Oh but what tales of woe those turned out to be.

There has been a lot in the press about how nightmarishly gruelling the shooting was on "The Revenant." In fact, it was as difficult as I've ever experienced. I'm no diva—I mean, I'm literally a bear, I defecate in the woods—but even I must go on the record to say that there were times during filming when I longed for death.

Alejandro turned out to be a harsh taskmaster, requesting take after painful take. "The light was wrong;" "Go again, we couldn't see Leo's face;" "Something about that didn't smell right—let's go again and watch out for smells." On and on it went, a carousel of sub-zero tedium. It didn't help that he insisted that we film only when Venus was aligned with Jupiter. This made for epic bouts of downtime. Now, I like backgammon as much as the next bear, but we were in temperatures that made the Antarctic look like a Turkish steam room. Sitting still meant icicles forming on our noses and, in the case of one crew member, frostbite of the head. Even I, a furry beast accustomed to the cold, asked a P.A. to get me earmuffs. I feared for the lives of my children, cubs who should not have had to suffer so profoundly for such pitiful IMDb kudos.

The inactivity was followed by shrieks of "FLY, MY BEAUTIES!" that prompted frantic bursts of action. I couldn't feel my paws. For many of the takes I was openly weeping. Alejandro barely noticed, demanding that we do the take again, but this time with our eyes shut, or with Leo naked, or with Alejandro naked. He was the puppet master, and we danced for him on frozen strings.

I regret to tell you that I began to take out my frustrations on Leo, poor fellow, which is why the mauling scene is so excruciating to watch. What you are witnessing is a bear at the end of her tether, attacking a man plagued by the same frustrations and discomforts as she. Alejandro loved seeing me go "maximum grizzly," of course, and egged me on. When he said that we could film only when the temperature was divisible by three, I remember picking him up and throwing him into a lake. It is only because we once shared those burritos that this did not cost me my job.

Until now I have refused to take part in the press junkets, for fear that I would break down. I ultimately felt, however, that I must write this opinion piece in the interest of spreading truth. If you are going to see this exploitative film (and I think you should—Leo really is superb), remember the untold torments behind the majesty on the screen. Recall the screams and the frozen paws. If you do not, my suffering—and the suffering of those who lost their lives in the white embrace of the Canadian mountains—will all have been for naught. And if you could mention my name and "Academy Award" together on as many social-media platforms as possible, that would also serve as a fitting tribute to the fearless and noble men and bears who didn't make it.