"Singing Voles are known for two remarkable behaviors. One is the construction of hay piles to provide food during the long northern winters. The hay piles are built off the ground at the base of a shrub or on a well-drained slope, and most of them are made by juveniles. Willow shoots, horsetail, and many other plants are found in the hay piles, which can be tiny but are sometimes as large as 30 liters. The second behavior of note is their ""singing,"" which is a metallic, ""churring"" sound. Their calls may be territorial, or they may be warnings of nearby predators. The Voles live in burrows dug in well-drained soil or under rocks."

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Mammal Species of the World