The evidence was clear; F109 had killed and eaten most of what had been a yearling wolf.
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Do mountain lions eat wolves? The answer to that is apparently be yes, but very rarely. Researchers with the Wyoming-based Teton Cougar Project recently found evidence that a female cougar ate a young wolf near the city of Jackson Hole. This event is not only rare because the mountain lion consumed the wolf, but also because the large cats rarely get the upper hand in conflicts with their rivals. Cougars and wolves often reside in the same habitat and conflict is not uncommon. As solitary hunters, mountain lions are nearly always outnumbered by the more social canines, and as a result very rarely win these occasional disputes. It is much more common for wolves to kill mountain lions.
According to the Jackson Hole News & Guide, at least one cougar managed to turn the tables. Biologist Mark Elbroch found that one of the cats he had been tracking, known as F109, had recently killed and consumed a young wolf.