Some insects overwinter in the pupal stage, emerging as adults in the spring. For example, many butterflies and moths spend the winter in their chrysalis or cocoon in a protected location. The eastern black swallowtail is a good example of this. Before the chrysalis is formed, the caterpillar spins a thin band or 'saddle' of silk to hold it to the stem, as well as attaching to a silk pad at the head. It may look like a delicate arrangement, but it's very strong, able to withstand months of icy blasts.
The chrysalis is well-camouflaged against the tree bark, looking like a dead leaf. However, it can be vulnerable to parasitization by some species of flies and wasps. The swallowtail's strategy is to literally 'throw them off the scent' by doing a little cleaning--tossing its frass (fecal pellets) off the plant before settling in. This makes it harder for the predatory insects to detect. Come spring, this beautiful butterfly will emerge from its winter haven.
So when you pass a native tree or shrub with a few curled-up leaves clinging on, look closely! You just might discover unexpected treasure.
Author: Lisa Schneider
Photo: S.Detwiler, wikimedia commons
The chrysalis is well-camouflaged against the tree bark, looking like a dead leaf. However, it can be vulnerable to parasitization by some species of flies and wasps. The swallowtail's strategy is to literally 'throw them off the scent' by doing a little cleaning--tossing its frass (fecal pellets) off the plant before settling in. This makes it harder for the predatory insects to detect. Come spring, this beautiful butterfly will emerge from its winter haven.
So when you pass a native tree or shrub with a few curled-up leaves clinging on, look closely! You just might discover unexpected treasure.
Author: Lisa Schneider
Photo: S.Detwiler, wikimedia commons
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