By Linda Ray
There is a new caterpillar charming us at the Habitat for All garden (HFA) this summer. Hyalophora cecropia moths are a native species in Maine but are seldom seen and thought to be declining in many areas of its range. Cecropia eggs were brought in this spring and hatched into tiny black larvae that thrived under tender care and observation into beautiful green caterpillars with red, blue, and yellow tubercles (which change color as they grow). Most people who visit the garden are especially fascinated to handle and learn about the life cycle of these animals and their unique beauty. This kind of interchange between humans and the natural world brings us a step closer to the appreciation and protection of the environment. And kids especially love playing with caterpillars.
In nature, the eggs can be found on the underside of leaves of their host plants, such as cherry, maple, and birch trees. Once hatched, they go through five instars before pupating (turning into a chrysalis). An instar is defined as a developmental stage between moltings. Each instar lasts about one week or so. By the time they are ready to pupate toward autumn, the caterpillars are four to four-and-a-half inches long and are green with a bluish tinge. At this point they will spin large brown cocoons horizontally on trees, branches, or wooden structures and remain in that state for the next 10 or so months. In the first two weeks of warm weather the following spring the adult moth will emerge.
The Hyalophora cecropis is a giant silkworm moth from the family Saturnidae and is the largest moth in North America, with a wingspan measuring up to seven inches. These giant moths do not have mouths or digestive systems and live for about two weeks. Once the adult moth emerges, its primary focus is to find a mate. The female will release very strong chemicals called pheromones, which in tiny doses (one 1/1000 of a kg) may theoretically attract up to 1 billion male moths. That is how powerful pheromones are in insect interaction. The males discover the pheromones with their antenna from up to a mile away. Females lay around 100 rust-colored eggs and are univoltine, meaning they have one brood of offspring per year.
The Habitat For All (HFA) garden crew are overwintering the pupae in a safe and natural environment with hopes that in the spring visitors to the garden will be able to witness the emergence of the stunning adult moths. The HFA garden glories in all the insects that inhabit the garden as part of the food web, as pollinators, and as is the case for the Hyalophora cecropis caterpillar’s cuteness and adult moth’s stunning and bold beauty. Come visit the HFA garden next spring and you might witness the emergence of an adult moth.
References:
https://entnemdept.ufl.edu/Creatures/bfly/moth2/cecropia_moth.htm
Engle, M. S. 2018. Natural Histories Innumerable Insects: The Story of the Most Diverse and Myriad Animals on Earth. American Museum of Natural History, Sterling Press, New York, NY
Photo Credits:
Hyalophora cecropis caterpillar photo by Linda Ray: Hyalophora cecropis moth photo by Marvin Smith. This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.