Entomology student camps out to crack mystery of who preys on monarch eggs

March 13, 2019

Only about 5 percent of monarch eggs survive to become butterflies. Doctoral student Andrew Myers set up 24/7 surveillance to determine who is preying on the eggs.

There’s a maxim that nothing good happens after midnight. Like most things in life, it depends on your perspective. If you’re a tasty monarch butterfly egg, it probably holds true. However, if you happen to be a hungry earwig or tree cricket, the party is just getting started. And if you’re an entomology graduate student studying monarch predators, like Andrew Myers, sometimes good research results only happen when you stay up with the nighttime bugs.

The topic of Myers’ doctoral dissertation research in Professor Doug Landis’ lab is determining how to improve breeding habitat for declining monarch butterfly populations. Monarchs have been disappearing across their range for the past 20 years, prompting great concern among those who love this beautiful, interesting insect. One suspected reason for the monarch decline is the elimination of their primary food as caterpillars — common milkweed — from croplands through modern weed management practices.

An everyday observer may notice that milkweed is still a common sight along roadsides, in gardens and in other grassy areas. But compared to 20 years ago, milkweed is now limited to a significantly smaller area. If we want to increase monarch numbers, we have to increase their breeding productivity in these remaining habitats, which is a major challenge for conservationists.

One way that we can potentially produce more monarchs from smaller areas is by increasing their survival during their egg and young caterpillar life stages. Only about 5 percent of the hundreds of eggs laid by each female monarch survive to become butterflies. Most are eaten by other insects and spiders. This brings me back to late night research.

To read more about Myers and his project, read his perspective in MSU Today: Andrew Myers: Working the Night Shift. Also, watch the video below on why Myers chose to study monarchs.