Sam is eager to find what caused his trap to spring; in opening the trap just a sliver to look in, he finds an angry weasel. The weasel proves to be fearless against Sam, darting off to escape and then turning around to stare Sam down before running back to attack him. However, Sam is amused by the animal, and describes their encounter as the beginning of a ''harassing but wonderful friendship.'' He decides to name the weasel "The Baron"

They turn out to be "friends" of a sort.

From Sam's notes:

"The Baron chews with his back molars, and chews with a ferocity I have not seen in him before. His eyes gleam, the lips curl back from his white pointed teeth and he frowns like an angry man. If I move toward him, a rumble starts in his chest that keeps me back. He flashes glances at me. It is indeed strange to be looked in the eye by this fearless wild animal. There is something human about his beady glance. Perhaps because that glance tells me something. I tells me he knows who I am and that he does not want me to come any closer." (p. 95)

Weasels are quick and vicious little animals. Before killing prey, weasels will bob back and forth and hop in a dance meant to intimidate the other animal. To kill it's prey, a weasel will clamp down on the prey's neck and keep biting until the animal is dead. This seeming viciousness, paired with the fact that weasels kill more food than they momentarily need, gives the weasel a bad rap.

Weasels, scientifically carnivores of the genus Mustela, come in a range of sizes but one basic shape: long and thin. In total, about 17 species exist, most of which are commonly called weasels, although the genus also includes polecats, stoats, black-footed ferrets, and one of the two remaining species of mink.

Larger weasels include the long-tailed weasel and the tropical weasel. They grow to 10 to 12 inches (25 to 30 cm) long and weigh 3 to 12.3 ounces (85 to 350 g). Their tails can grow to around 4 to 8 inches (10.2 to 20.3 cm) long.

Though weasels can dig their own burrows quite quickly, they sometimes take over other animals' burrows and make them their own. They have even been known to take over termite hills. Weasels stay warm by lowering their metabolism and curling into balls inside their burrows.

"I looked for signs from The Baron Weasel. His footsteps were all over the boulder, also slides where he had played. He must have been up for hours enjoying the new snow." (p. 5)

Camouflaged fur helps the weasels avoid wolves and other predators. This has served them well over time evolutionarily. However, with climate changing maybe not so much now.

By Chapter 13, Sam is happily settled into his new life in the forest. He is enjoying the changing of the seasons as the leaves turn color, a new harvest is ready for gathering, and many of the animals prepare for migration or hibernation. Along with these changes, Sam observes the Baron changing his mantle, or fur, from his summer coat to his heavier winter coat.

When there is deep snow, weasels of both colours tend to hunt underneath it, which, after all, is where the small rodents are, so the predation rates for both species are reduced. In periods of winter without snow, however, white weasels are much more conspicuous than brown ones. In recent years, because of climate change, there have been more days without snow, and the date when snow disppears in the spring has become progressively earlier.

The conclusion is that the proportion of white weasels in the population is influenced by predation rates due to lack of camouflage during the previous winter.