Predators and Competitors
The least weasel is small enough to be preyed upon by a range of other predators. Least weasel remains have been found in the excrement of red foxes, sables, steppe and forest polecat, stoats, eagle owls and buzzards. The owls most efficient at capturing least weasels are barn, barred and great horned owls. Other birds of prey threatening to the least weasel include broad-winged and rough-legged buzzards. Some snake species may prey on the least weasel, including the black rat snake and copperhead. Aside from its smaller size, the least weasel is more vulnerable to predation than the stoat because it lacks a black predator deflection mark on the tail.
In areas where the least weasel is sympatric with the stoat, the two species compete with each other for rodent prey. The weasel manages to avoid overly competing with the stoat by living in more upland areas, and preying on smaller prey and being capable of entering smaller holes. The least weasel actively avoids encounters with stoats, though female weasels are less likely to stop foraging in the presence of stoats, likely because their smaller size allows them to quickly escape in holes.
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