April 25 Old Cicada Shell

Tonight we went for an after dinner walk at Hoyt Park to look for new birds. Above the bluffs we found several tiny kinglets, of the ruby-crowned variety, eastern phoebes and one blue-gray gnatcatcher. Plenty of wildflowers were up in small patches and the woods are already bright green with new honeysuckle leaves in many spots. Heading down the stairs to the lower level, we caught sight of a hermit thrush on a high mound and a rabbit trying to stay hidden. While inspecting some flowers, I looked under a log and some leaves and uncovered this cicada skeleton. According to my insects field guide, there are 9 species of cicada in Wisconsin, but dogday cicadas (Tibicen canicularis) are by far the most common, and so I will make an assumption that this is one of them. These cicadas will begin life as eggs that hatch inside tree twigs. They drop to the ground and burrow under as nymphs and feed on tree roots for two years before reemerging. Dogday cicadas do not have synchronized lives, so new ones come out from the ground every year. When the nymphs emerge in July, they will walk onto the tree trunk, split their skin in half, and push itself out with a soft winged body that hardens in a few days. The adults don't even eat anything, they just make those electric buzzing noises by vibrating their tymbals (organs on the side of their abdomen). They look for a mate and then quickly die off. There are many other cicadas with a synchronized life cycle which only emerge all together, with spans of 4-17 years between. Brood XIII, the 17 year cicadas that live in southern Wisconsin, are scheduled to make their next appearance in summer 2024. A little long to wait, if you ask me. In the meantime we can enjoy the low hum of the dogday cicadas this July and August.