Field guides will inform you that pikas are herbivores. Even their digestive systems mark them as vegetarians as they ferment food in their guts. Hik knows that pikas are eating the birds because his research team has analyzed hair and feces collected from the pikas. Using a technique called stable isotope analysis, they can determine what the animals have been eating. Hik wants to determine how much of the pikas' diet is made up of bird meat.
Bird brains are obviously a delicacy for the pikas.
Most animals, when they eat a carcass, will go for the guts and the brains. They're high in fat and proteins, and they're easily digestible. In the future Hik hopes to determine how this meat supplement might affect the pikas' ability to survive and reproduce on these isolated nunataks. He has been comparing the icefield pikas with two other groups of pikas in the Kluane area. These groups, one in the Ruby Range and another near the Slims River, stick to a more traditional vegetarian diet.