Christine's Mosquito Experiment

Guest blog: Christine N.

Hello, my name is Christine and I’m from Redwood City!  I have set up my traps near where I live. For my experiment, I wanted to test to see if mosquitos had a preference for different types of water. I made sugar water, salt water, and dog food water. I also laid out a bowl of just plain tap water as the control. So, my independent variable will be the type of water while my dependent variable will be the number of mosquito larvae in the container. Other variables such as bowl type/size, amount of water put in, location, etc. will be kept constant.

WEEK 1: For all of the traps, I mistakenly let the water dry up completely. So, I added more water to each of the bowls. Due to the absence of water, I didn’t see any mosquito larvae in any of the bowls. 

WEEK 2: The water is still evaporating very quickly despite the fact that I pour water in more frequently. Due to this issue, I have moved all of the bowls to a shaded location. In the tap water bowl, there is some leaves in addition to the stick I had initially put in. The dog food water bowl is starting to smell and compared to the others, the water is the dirtiest in this bowl. The salt and sugar water is overall still very clean and only have some leaves or dirt inside. Still, there are no larvae in any of them.

WEEK 3: For the sugar water, there are some water bugs floating on top but no larvae. The other bugs, however, are still alive and moving about. The saltwater bowl has tipped over (maybe due to wind?) and the water is very minimal. The stick has also fallen out. There were no larvae in that bowl as well. The dog food water bowl has started to grow fungi and due to this, I’m not sure whether the mosquitos will be more or less attracted. For now, I will leave the fungus as is to let the experiment run without outside interference. The control tap water is doing fine and overall clean. There is still debris such as leaves and dirt in all of the bowls. 

Out of curiosity, I took a sample of each water and put them under a microscope. I interned at a community college so I was able to access slides/covers and borrow their microscopes for this. But, I did not find anything too interesting. I have attached photos of this process.

WEEK 4: The stick for the sugar water has seemingly disappeared. Perhaps it was due to the wind. I have added a new stick and some more water. The bowl is starting to get dusty and there are some spiderwebs starting to form. The slat water is doing well. Just like sugar water, there are some bugs in the water but it is only parts of them. For example, there are some insect legs and other miscellaneous parts. There is also more dirt at the bottom of the bowl. The fungi in the dog food water bowl have grown and are starting to smell horrible. The tap water, just like the others, has no larvae in them weirdly.

Once again, I took some samples to the lab and checked them out under the microscope. I also tried to grow some bacteria from the water in agar plates to see what would grow. I have attached photos of this process below.

WEEK 5: There are bugs moving around on the surface again of the sugar water bowl but the sample does not have any mosquito larvae. Compared from last week, there is a lot of dust and dirt accumulating in this bowl. The saltwater bowl was empty apart from dirt and some other plants like grass. There were no bugs on it. The dog food water still smells unpleasant and the fungus is starting to grow very large. The water in the tap water control seems to have spilled out. Compared to the other bowls, the water level is much lower. Other than that everything else is the same with no larvae visible.

I took a sample of both the water and fungus and put them under the microscope again. I also tried to grow them in agar plates again. I have placed more photos below.

Conclusion: None of my bowls were able to produce any mosquito larvae. Perhaps this was an error in my trap set up or maybe there were not many mosquitos in my area in the first place. However, taking the samples to the lab and examining them under a microscope, and growing them in agar plates was interesting to see the bacteria in the water.

About the author: Christine is a high school student who participated in the NASA SEES Earth Christine Nam  ​​​​​​​System Explorers research team. Her 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 ( ​​​​​​​

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