Milbert's Tortoiseshell

Milbert's Tortoiseshell (Aglais milberti), a striking and unmistakable Lepidopteran, is typically a butterfly of mountain meadows.  I found this individual "puddling" in a meadow near Lake Tahoe, along with a Hoary Comma.  Commas and Tortoiseshells are closely related members of the Brush-foot family (Nymphalidae).


Many butterflies are attracted to damp soil and engage in a common behavior known as "puddling."  While we typically picture butterflies delicately sipping nectar from flowers, many species obtain their nutrients from a surprising variety of sources, including rotting fruit, sap, dung, carrion and mud.  It is believed that butterflies, especially males, obtain salts and minerals from mud.

The brown underside of the wings provides camouflage as these butterflies hibernate during the winter. 
Also note the butterfly's extended proboscis (feeding organ) taking in nutrients from the mud.

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