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...a club for people who never stop learning

The Scientech Club provides a forum for weekly presentations and discussions in the fields of science and technology and other topics for the enlightenment of its membership.

Regular, one-hour Meetings are, with the exception of holidays, held every Monday at noon at The Northside Knights of Columbus, 2100 East 71st Street, Indianapolis. Club Members, as well as the general public, may attend our Regular Meetings for a nominal contribution to pay for the facility. For those who wish, a buffet lunch may be enjoyed before the meeting. Occasionally, instead of a presentation, members and their guests may take a tour to a place of interest, such as a plant or historical site.

The Scientech Club is associated with two outstanding local charitable Foundations, established by Scientech members to promote science education: The D.J. Angus - Scientech Foundation and the R. B. Annis Educational Foundation.

Vol 91 No 15 - April 21, 2014

Where Are All the Butterflies?

Presented By: John Thieme, BS, Entomology, Purdue University


John Thieme

John Thieme received his training as an entomologist at Purdue University. He spent 31 years working in several different divisions and roles at Syngenta Crop Protection in various parts of the country specializing in insect and weed control. In retirement, he now focuses his attention on "good insects," especially butterflies. As a way of staying physically active, he makes roadside observations of butterflies while riding his 27-speed recumbent tricycle on a 30-mile round trip route from Zionsville to Lebanon. He travelled more than 8,600 miles on this path from 2005 to 2013 while studying central Indiana butterflies.


Buckeye Butterfly

Starting life as an egg, butterflies progress to become a larva, then they transform to a pupa (chrysalis), and finally they emerge as the beautiful butterfly. Interestingly, they taste with their feet, and smell with their antennae.

Of 10 native Indiana species considered threatened or endangered, John has not seen any of them during his rides, or for that matter, during his more than 50 years of butterfly observations within the state. Of 30 well known species in Indiana, John's personal observations in the past 50 years are that 60% of these have become less common, 30% are similar in occurrence, and only 10% are more common. In 2012, fully 91% of the butterfly counts by him were accounted for by only 3 species (the Buckeye, Alfalfa, and Cabbage White Butterflies) and 97% were accounted for by only 5 species. The remaining sixteen species listed as observed in this study, only made up a meager 2.8% of his counts. This leads to the question raised in the title: "Where are all the butterflies?"


Alfalfa Butterfly

While a number of factors are considered threats to butterflies, habitat loss, extreme weather, and a sharp decline in native larval host plants and an increase in non-native plants are believed the most destructive factors. It is known that butterflies can be very specific and selective about the types of plants and trees which support them, and over time changes in the host environment (e.g., introduction of non-native trees and plants in Indiana) are causing reductions in butterfly populations. Extreme weather is well known to have negative impact on plant populations, but it is less well known that plant and butterfly populations are closely linked, thus explaining some of the adverse effects of weather on butterflies. Some of our most successful species of butterflies include some species that cannot survive Indiana winters but migrate north from southern states each spring.


Cabbage White

Many of the rare Indiana species of butterflies are concentrated in niche environments that are favorable to their life cycle (native forests, meadows, and wetlands, etc). This explains why we see so few of them in roadside and backyard habitats common throughout Indiana.

We need to be concerned about butterfly populations because they are indicators of general biodiversity. What can we do to help improve the future of butterflies? John provided a list of ways to help including planting specific native larval host plants and good nectar bearing plants, and a more judicious use of insecticides, herbicides, tillage, and vegetative removal. "Butterfly gardens" were especially encouraged.


Painted Lady

John clearly enjoyed speaking to us about his 3-wheeled investigation of butterflies in central Indiana. Moreover, his lepidopteran passion has had the added benefit of keeping him in excellent shape in retirement.

Notes by Ray Kaufman and the speaker