A Novel investigation that aims to conclude what style of mosquito trap is most effective for reducing mosquito populations in relation with the cost of creating it.
INTRODUCTION
Ovillanta trap is a form of mosquito larvae trap created using discarded motor vehicle tires. When I was first introduced to the Ovillanta trap by Dr. Low, I became immediately set on building one myself. I didn't think it would be very difficult. After all, I have probably spent more time in my grandfather's basement workshop surrounded by power-saws and drills than anywhere else in the world. However, this was not the case. It took me hours in his basement and many different tools to slice through the tire's thick edges, which were packed with stainless steel cables. Not only did I cut the tire but also my hands on numerous occasions as the sharp wires easily pierced skin.
On my drive home I couldn't help but feel like I would have been better off spending 30 seconds to slice a water bottle in half and build the traditional bottle-trap I had seen online, as opposed to the 2 hours and heavy machinery it required making the Ovillanta. This sparked the inspiration for my experiment. I figured, there are so many varieties of trap displayed online. If I was an average citizen trying to control mosquito's in my backyard, how would I know which to choose? I would want the most "bang for my buck": or the trap that provides the most productivity in comparison to how much input (time, money, etc.) it required to create it. Therefore, my experiment attempts to answer the research question, how will 4 different traps with varying levels of input (time, money, etc.) required to make them compare in terms of how many mosquito larvae they are able to capture?
METHODS
First, all four traps were designed using different levels of input, meaning time and money. Additions including black mesh and rope/string to hang them from branches were made to the higher input traps. All traps were set out in very close proximity to each other so that location would not alter data. A stick was placed inside each trap to allow for easy laying of eggs by female mosquitos. Then, each day the traps were checked to ensure that they had not fallen or broken. Every Sunday, I brought together my cellphone, microscope, sampling plate, and other materials to then sample from the traps. I recorded quantitative data in my charts and uploaded photos to the MHM database.
RESULTS
Week one results: ANTS! In the bottle and cup traps, there was a massive ant infestation. I decided that for week two, I am going to hang the cup and bottle traps and see if that changes anything. I am still on the hunt for my first mosquito larvae, but I am hoping for some exciting results when I check next Sunday. For now, there are no clear advantages of any of the traps, but I will update this as more accurate results start to come in.
Week 2: the ovillanta is definitely starting to pull ahead. When I dumped the contents into a bucket to better explore them, I found tens of Aedes larva that I photographed below. I am still getting the hang of using the microscope to take photos. I find that making the traps hang from a branch using string or rope provides many benefits as the traps are much less vulnerable to slugs or ants. Additionally, I am finding those with more water in them seem to be outperforming those with less. The trap made from a 16oz Poland Spring water bottle does not seem to be faring well.
Video of larva https://drive.google.com/file/d/1iEfGGTzgQ_K2oLAp9u2Q20th9Z-F7l7W/viewusp=sharing
Week 3: Moved locations, now at my grandparents shore house where I have set new traps and hope to compare what I find to back home. Before I left, I captured some very high quality larvae photos which I have attached below. Figuring out how to best utilize the microscope phone attachment took some time, but once I was able to do so I captured some really good images. I also had my first encounter with planaria or other microscopic worms in my Ovillanta trap. I have done some research and it seems like these can often be predatory towards mosquito larvae so I am looking into them as a source of mosquito mitigation. I am running a current experiment in which I introduce 5 worms into an environment with 10 larva and see how the two species interact. It is very exciting to see real mosquito mitigation techniques play out before my very eyes
Week 4
For the first time in this experiment, the quantity of larva week to week in the Ovillanta trap has decreased, because a new organism shown below has taken over. The 16oz water bottle trap has not performed well at all, but all the others have caught significant quantities of larva. I have also caught some late stage larva and pupae so it is cool to see the mosquitos at different stages of life. Some worm-like larva, similar in size and activity to mosquito larva, but definitely not mosquito larva took over the Week 4 sample for the Ovillanta trap. I did some research and they seem to be some type of Planaria. Here are 3 videos: the first is of the mystery organism in a bucket, the second is under a microscope, and the third shows the organism interacting with a blade of grass. My experiment from last week of introducing these worms with larva in a small closed environment did not work, as the cup got knocked over. Either way, I am looking forward to studying the interaction of mosquito larva and this wormlike organism in coming weeks.
Video of mystery organism in bucket https://drive.google.com/file/d/1MeorbJelhDxHh3tIc2dBQ1HM7Iudnt8a/view?usp=sharing
video of mystery organisms in sample https://drive.google.com/file/d/1EIqeGRAPBvS_YuYpydyil3wHFUlJZecm/view?usp=sharing
video of mystery organism interacting with grass https://drive.google.com/file/d/1cHAdfa2fxy_rYqHa-2kpaz3H2axKRczt/view?usp=sharing
DATA
Conclusion
As of this moment, after collecting 4 weeks of quantitive data and qualitative observations, my advice to a civilian that wants to create their own mosquito trap that is both effective and cost-efficient would be as follows:
Investments that are definitely worth the time/cost:
Investments that show inconclusive results:
Final Thoughts
This experience taught me a lot about the scientific process, and how you always have to be prepared for the unexpected. Just when it looked like I was coming to a clear conclusion that the Ovillanta trap was worth the time and effort I put into creating it, worms entered the sample and it actually underperformed compared to the 64 oz bottle trap in week 4. However, this is the interesting part about science, it never gets repetitive. You are always discovering new things, testing new theories, and being forced to change what you previously thought to be true. I hope to continue on this path of scientific experimentation and research in the future. Thank you Cassie and Dr. Low.
About the author: AJ is a rising senior at Ridge High School, Basking Ridge, NJ. This blog describes a mosquito trapping experiment conducted as part of the NASA STEM Enhancement in the Earth Sciences (SEES) summer high school research internship. His virtual internship is part of a collaboration between the Institute for Global Environmental Strategies (IGES) and the NASA Texas Space Grant Consortium (TSGC) to extend the TSGC Summer Enhancement in Earth Science (SEES) internship for US high school (http://www.tsgc.utexas.edu/sees-internship/).
