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photo courtesy Emily Geest

Charlotte Reilly
News Editor

Emily Geest found a way to combine two passions, parasitism and butterflies, in her master’s program at the University of Nebraska at Omaha.

Geest is monitoring milkweed gardens to assess the effectiveness of the gardens as conservation strategies. She determines if monarchs are coming to them, if they are laying their eggs there and if the eggs are surviving from egg to adult. She also keeps track of how many of the butterflies are parasitized by flies.

Monarchs, especially ones within the Eastern population, have had a population decline of about 80 to 90 percent since 1995, Geest said. A lot of that is because of habitat destruction. Milkweed gardens have helped re-establish their habitat.

The monarchs reached their lowest population in 2012 because of a drought that reached across the Midwest. Their numbers have gone back up, but are nowhere near where they were before 1995.

“We don’t know if the increase is a long-term trend or if it is just because the weather has improved,” Geest said.

Geest monitors 13 gardens. About half of them are residential gardens, and the other half are conservation sites which are known as prairies. She visits each site every four days. Last year, she managed all of the sites on her own, but this year some undergraduates are helping her monitor the sites.

At the site, she counts all of the milkweed and writes down all of the species of milkweed that are present. Then, she takes tallies of the eggs. Depending on what stage in which the caterpillars are, she takes them back to the lab.

The species of caterpillar she is studying has five instars, or growth stages. She takes tallies of each instar, and all caterpillars at their fourth or fifth instars are brought back to the lab. The biggest threat of mortality in the later instars is parasitism. They have reached the maximum amount of exposure to the fly by instar four, so Geest is able to take them to the lab and monitor whether they will be parasitized.

Geest visits her lab in Alwine Hall every day and feeds all of the caterpillars. If they are parasitized, she waits for the maggots to come out of the caterpillar and then counts them. If the caterpillars turn into a chrysalis, she moves them farther down the table so they don’t get disturbed. When they come out of the chrysalis as butterflies, she moves them into a butterfly cage for a day so their wings can dry. The next day, she brings the butterflies back to their original site.

Geest said her favorite aspect of the project is working with the public.

“Everyone loves monarchs. They know what monarchs are,” Geest said. “If you study birds you would have to explain what kind it is, but when they hear monarchs, people say, ‘Oh it’s the symbol of Papillion!’ Everybody loves them and always wants to talk about them.”

After graduation, Geest said she hopes to get her Ph.D. work as a research biologist.

She wants to focus her research on grassland butterflies.

“The grasslands have been one of the biggest habitat losses,” Geest said. “All of the butterflies are suffering, not just the monarchs.”

Though she is excited to earn her Ph.D., Geest said she will miss UNO.

“When I came here, I loved everything,” Geest said. “I loved my advisors. I loved the biology department. It all felt right.”

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photo courtesy Lindsay Brown

Charlotte Reilly
News Editor

The University of Nebraska at Omaha biology department first began research on migratory sandpipers and plovers in 2004.

Joel Jorgensen studied the birds for his master’s project. Dr. John McCarty and Dr. L LaReesa Wolfenbarger continued to monitor the sites after he graduated. Now, UNO student Lindsay Brown is monitoring the birds for her biology master’s project.

Brown explained that the birds occupy agricultural fields in the rainwater basin of central Nebraska. It is hard to monitor their population trends because the birds migrate. Migration is energetically demanding, so it is important to determine if it is risky for them to stop in agricultural fields.

Brown’s preliminary analysis has shown her that the birds are choosing sites based on the topography of the landscape. Each bird behaves differently and is drawn to different landscape features. Some occupy flat land while others occupy land with a variety of slopes.

The buff breasted sandpiper and upland sandpiper typically choose sites higher in elevation in the rainwater basin.

The Buff-Breasted Sandpiper is one of many birds Brown studies – photo courtesy Lindsay Brown

“It’s interesting that the two that are showing more courtship behavior choose the same landscape feature,” Brown said. “It could be so that they are a little more visible.”

The American golden plovers are choosing sites with many different slope degrees. They are a resting bird and are molting into breeding plumage. Brown believes the variety in slopes may provide them with more protection.

Brown visits each site regularly. She does point counts to determine what fields the birds are occupying. Then, she watches the birds to understand flock behavior. Finally, she picks an individual bird to watch for three minutes to understand how the individual is using the site.

Brown said she hopes her research will explain why the birds display certain characteristics, what makes them choose certain sites and if the fields are safe habitats for them.

After Brown graduates, she hopes to work for an organization that conducts research, and then uses the research to implement management practices. She believes her research experience at UNO will help her in her future career.

“Both UNO and the biology department really try to support their graduate students,” Brown said. “The biology department provides chances for students to apply for money for their projects, and provides opportunities to share their results.”

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