Episode description

Hi, Everyone! In today’s episode of the Backyard Ecology podcast we are talking with Shelby Fulton who is a terrestrial biologist with the Kentucky Nature Preserves. Our conversation focuses on moths and how they survive the winter. We also talk about how diverse moths are and ways to observe them during the winter.

The number of different moth species is astonishing. For example, there are over 2,500 different species in Kentucky alone. Many species of moths are extremely small – almost too small to see. Others are much larger and easily identified. How a moth spends the winter is determined by its species. Some species overwinter as eggs, some as caterpillars, some as cocoons, and some as adults.

The most common overwintering strategy is as a cocoon (pupae). There are also quite a few moths that overwinter as adults. Moths that overwinter as adults tend to have fluffy, “furry” abdomens. Some of these species are dormant all winter – basically going into the moth equivalent of hibernation. While others may be active and fly around on warmer winter nights.

In addition to the fluffy, “furry” abdomens, moths that are active on warmer winter nights also tend to have other physiological adaptations to help them stay warm. These adaptations usually include the ability to shiver and warm themselves up enough so they can fly. Some species have internal adaptations that allow the moth’s hemolymph (insect blood) to help keep itself warm. Those internal adaptations prevent the heat generated from the moth’s shivering behavior from being lost to the outside environment as quickly as it would be lost without those internal adaptations.

Many of the moths that overwinter as adults are relatively small (dime to nickel sized) and tend to be narrowly triangular and kind of drab colored. But some of them, like the herald (Scoliopteryx libatrix), which is featured in the photograph associated with this episode, are beautiful shades of brown or have intricate dashed patterns.

One of the primary places that moths overwinter, whether as adults, caterpillars, or cocoons, is in the leaf litter. That is one of the reasons why leaving your leaves on the ground and not throwing them away, burning them, or mulching them is so important if you want to provide habitat for moths, or even butterflies.

If you want to try and see some of the species of moths that overwinter as adults in your area, then you can try a sugar bait. There are many different sugar bait recipes, but they all include some form of alcohol, sugar, and fermented fruit. Mix everything up and spread it on a tree on a warm winter night, then check it periodically to see if anyone shows up. Taking pictures of any winter moths that show up and posting them to iNaturalist is a great way to get help identifying the moths. It will also help researchers learn more about what species of moths are active in your area during the winter, because this is yet another relatively understudied area of backyard ecology.

• Office of Kentucky Nature Preserves website
• Shelby’s email: shelby.fulton@ky.gov
• iNaturalist: https://www.inaturalist.org/
• Backyard Ecology's website
• My email: shannon@backyardecology.net

Photo credit: Shelby Fulton, Office of Kentucky Nature Preserves