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The least weasel is a small mammal with a huge appetite. Its sharp teeth and claws can take down animals larger than its own diminutive size. Small rodents are preferred prey, but will chase down rabbits, birds, frogs and insects when necessary.

Because of its size and very active lifestyle of hunting, mating and burrowing, the least weasel must eat roughly between 40 - 60% of its body weight every day. However, its appetite to kill is far more voracious than the amount it actually needs to survive. Least weasels are known to take prey in quantities larger that it can consume. Though it will stockpile any overkill in nearby burrows, the surplus is often left to rot as they prefer fresh meat.

Though a ruthless hunter, the least weasel does play an important role in its surroundings. Its feverish hunting reduces rodent population which benefits nearby agricultural fields. There is also no need to worry about overpopulation, especially in Indiana. Historical trapping, habitat loss and land development has kept the least weasel population small in our state for many years. The least weasel has a short lifespan, but it is also a species of special concern in the state as it is very rare. Today, least weasels are only found in the grassy fields or marshes of northern Indiana.

Interesting Facts about Weasels

• There are two species of weasels native to Indiana: the long-tailed weasel (Mustela frenata) and the least weasel (Mustela rixosa).
• The long-tailed weasel is larger in size with males ranging anywhere from 14 to 16 inches long and weighing 3 to 7 ounces. Least weasel males range from 8 to 9 inches long and weigh about 2 ounces. Males of both species are larger than the females.
• The species can also be differentiated by their tail; the long-tailed weasel has a black tipped tail, while the tip of least weasel's tail is brown in summer.
• The coat of the least weasel, as with all weasels, will turn white in the winter. Least weasels are found only in the northern part of the state and are more likely to turn completely white. Species found in warmer climates will stay partially brown.
• The white winter fur of the least weasel glows a bright lavender color when under ultraviolet light. 
• Because weasels have a high surface area to weight ratio, they conserve body heat in winter by curling into a ball and lowering their metabolism.