Researcher investigates environmentally friendly mosquito management
June 27, 2016
By Rachel Machacek, University Public Affairs
Virginia Commonwealth University alumna Katie Bellile has always been very clear about what she wants. From a young age she knew she wanted to go to VCU and immerse herself in environmental studies.
Bellile, 28, grew up in Richmond around the university where her mom was working toward a master’s degree in urban planning. She remembers being inspired by the Eugene P. and Lois E. Trani Center for Life Sciences building, which was new at the time.
Last year, Bellile graduated with a master’s degree in environmental studies in Life Sciences after completing her undergraduate degree in the same discipline, and started her career at Stantec as an environmental planner, protecting limited freshwater resources. Now, the research she conducted as an undergraduate student has been published — a unique achievement. And she has done it all as a single mom.
Bellile’s paper is an investigation of environmentally friendly mosquito management. Specifically, she looked at the combination of biological pesticides and leaf litter in controlling the emergence of adult mosquitoes from the egg and larval stages. The paper was published this month in the Journal of Vector Ecology, and is the culmination of research Bellile conducted with her faculty mentor James Vonesh, Ph.D., associate professor in the VCU Department of Biology in the College of Humanities and Sciences.
We caught up with Bellile recently to talk about her work and the newly published paper.
How did you become interested in pesticides and mosquitoes?
My original interest was chemical pesticides from agricultural use getting into the freshwater system. I began to look at some of the problems associated with these pesticides and it led me to an interest in biological pesticides, which are better for the environment in general.
So far, research shows that biological pesticides like Bti [Bacillus thuringiensis serotype israelensis] primarily target mosquitoes and don’t have large effects on the rest of the community. So frogs, for example, aren’t directly inhibited by products like Bti.
So why wouldn’t everyone use Bti?
Well, I started looking into the existing literature only to find that even though Bti has been examined by many scientists, there was not consistency in its efficacy. Sometimes it reduced adult mosquito emergence 99 percent and, other times, less than 30 percent, so there must be an agent increasing or decreasing its efficacy. But what?
And the sleuthing begins. What did you find out?
When I read through all the literature, I realized quantity of leaf litter around mosquito breeding grounds is a constantly changing factor. I thought perhaps there is a relationship to the amount of leaf litter and the changing efficacy of Bti.
What did you observe in your research?
That leaf litter in combination with Bti created an ovitrap. Essentially, the leaf litter encouraged the mosquitos to come to the site and lay their eggs rafts there and Bti would have greater effect because there was a larger mosquito population present.
So you tricked the mother mosquitoes into depositing their eggs in an egg-friendly amount of leaf litter and then used Bti to kill the larvae?
Yes. Instead of deterring mosquitoes from laying eggs in your yard, stream or river, you gather a larger population at your site and therefore you’re able to get rid of more of them. My observation showed that they were less likely to colonize an area that only had Bti or low leaf litter than they are to colonize an area that has high leaf litter.
That must have been a lot of mosquito egg counting to verify your results.
That was actually the highlight — exploring the communities that established in my mesocosms. I loved collecting the data. I loved keeping count of every egg raft. I loved the feeling of accomplishment after I spent six hours with my face one inch above the water counting egg rafts or using a turkey baster to suck adult mosquitoes from the emergence trap. I loved that it was hard.
It’s a lot of work. Were you working on your own?
I did decided on the plan on my own and kept detailed records, found volunteers, set up the experimental area, monitored my mesocosms and collected data. My research assistant, who is now my husband, helped with the heavy lifting of mesocosms and tasks that required someone to take measurements while someone else wrote data down.
What were you surprised to learn?
How hard it is to spend a year developing an idea, a year performing the experiment and then trying to squeeze all the hard work you’ve done into something someone will actually read. If I had it my way, my paper would have been 30 pages long. Dr. Vonesh and I worked really hard to use concise language and it’s less than 10 pages now. I really wanted readers to know all the work that had gone into it and all that I had learned, but instead I learned how to stick to the facts that are pertinent to your main idea and eliminating everything else.
What was your biggest challenge?
This was a complex project with multiple factors. I was looking at Bti presence and absence, leaf litter presence and absence, as well as mosquito emergence numbers in over 28 mesocosms. Presenting the data so it displays in a way that is accurate and defensible are factors that go into statistical analysis. Wrapping my head around all the math that had come from my own idea was wild.
And what was the highlight?
Really it’s being a scientist for the first time because it’s something I’ve wanted for so long and worked so hard for the privilege of doing an experiment at the VCU Rice Rivers Center. I was excited the whole time I was doing fieldwork. I truly love the time I spend alone studying the woods and water. It allows me to put space in my soul.
You were raising a young daughter alone the entire time you were in school. How did you stay motivated and on track?
I have a strong supportive family who never let me feel like being a young single mom should stop me. My daughter has been my constant motivation. I knew I had to study really hard to be the best I could be for her. I read a lot of my textbooks to my daughter as bedtime stories so she has benefited tremendously. She, too, is a straight-A student.
This article was originally published in VCU News on June 23, 2016.