by Pat Jaquith
pat@westvalleynaturalists.org

The sight of a Mourning Cloak butterfly is a sure sign of spring to me! In late fall, they crawl behind loose bark on a tree where they increase the level of glycerol in their blood, convert excess water in their bodies into a gelatin-like substance that doesn’t freeze, and spend the winter. As spring warmth arrives, they reverse those properties and start flying sooner than many others! Many butterflies endure the winter as eggs, caterpillars, or in a chrysalis. A few, like Monarchs, migrate to warmer climates.

The fragile-looking beauties in these photos live only one or two weeks. They do not grow or make body repairs, and many never eat, so most of the butterflies pictured above are quite freshly out of the chrysalis. These butterflies’ job is to find a mate and lay eggs on plants that will nourish the larvae. Not just any plant will do – usually they have very specific requirements. They accomplish all these tasks while evading their predators: birds, spiders, wasps, dragonflies, and more. Their tiny eggs develop into tiny caterpillars which eat and grow, rarely leaving the plant where they started. When they reach full size, they construct a chrysalis that shelters them while they grow legs, antennae, wings. . .and when the development is complete, out comes the butterfly!