The Discovery Center at Ridgefield

First Spring Butterflies by Allison Archambault
 
While hiking in late March, I saw my first butterfly of the season; a mourning cloak butterfly (Nymphalis antiopa).  I wondered how could it be here so early when most butterflies are en route with the spring migration, and what is it feeding on as the nectar plants aren’t out yet?  A few days later I saw a few more of these distinctive large butterflies, with their dark maroon/brown wings with a cream edge and iridescent blue spots just inside the light edges.  This got me curious, so I did a little research.  I learned that the mourning cloaks are out so early because they don’t all migrate like many other species of butterflies (the monarchs for example).  They over-winter hiding in tree cavities and under loose bark in a state similar to hibernation.  This gives them an advantage come the spring in that they don’t have to travel long distances to return, and can get a jump start on mating.  The adult mourning cloaks feed primarily on tree sap and depend less on nectar, which would explain how they can survive this time of year.  They also live up to a year, which makes them one of the longest living butterflies, if you consider how adult monarchs only live for two to six weeks!  In the spring, the females lay their eggs on host plants such as willow, elm, hawthorn, hackberry, wild rose and poplar.  The larvae which emerge are called spiny elm caterpillars, and they have black bodies with red dots down their back, red legs and a number of long black spines, plus shorter spines with white on the tips.  They have voracious appetites for such small creatures and can grow up to two inches long before they pupate and go through the fifteen day process of metamorphoses before the beautiful adult butterflies emerge.

Mourning cloak butterfly (Ann Murray photo)