The butterfly s four-inch wingspan is robed in rich chocolate brown, edged by a creamy yellow margin. A row of iridescent violet to blue dots highlights a black band lying within the creamy border. The underside of the wing is dark gray to black bordered by a dirty looking cream-colored band. This cryptic coloration truly cloaks the butterfly when it rests with its wings closed on a tree trunk. In the warmth of summer, love is in the air for the mourning cloak.
Males establish territories.
Within their turf, a favored branch or leaf serves as a perch to wait for females that wander through. During days of waiting, mourning cloaks often bask with their wings open in a sunny spot on the path or on a sunbeam striking a leaf. After a receptive female enters his territory and mates, the female searches for willows on which to lay her eggs. American elm, white birch, aspen or hackberry trees are sometimes suitable substitutes. Most butterflies lay single eggs on separate plants, but mourning cloaks lay up to 250 round yellow eggs in a tight, one-layered cluster around a twig.