DIY Mosquito trap- good for about 2 weeks... then replace ingredientsMaking a Mosquito Trap Because mosquitoes are attracted to the CO2 we breathe out, I started looking for ideas that used CO2 as the bait for the mosquito trap. I did think of dry ice but it does dissipate fairly quickly. I found a cached link on Google here. It seems to be active again now. I've rewritten the instructions some and hopefully it will work as well. Thanks to the students for their hard work on this project. I've used some of their photos for illustration. Supplies: 1 2 liter soda bottle a sharp knife black paper tape candy thermometer Take a 2 liter soda bottle. Cut off the top right below where it starts to narrow for the top, invert and place inside the lower half. Make a simple sugar syrup. Ingredients: 1 cup sugar 1 cup water 2 cups cool water 1 tsp. active dry yeast Directions: Bring 1 cup of the water to a boil. Dissolve the sugar into the boiling water. Once the sugar is dissolved completely, remove the pan from the heat. Stir in 2 cups cool water, stir well. Check the temperature of the syrup to make sure it is no hotter than 90 degrees F, if hotter, let cool to 90 degrees F, add 1 tsp. active dry yeast, no need to mix. Put syrup in the bottom part of the bottle, using the cut off neck piece, leave in place. Be sure to seal the two parts of the bottle with the tape. The fermenting yeast will release carbon dioxide. Put black paper around the bottle since mosquitoes like dark places and carbon dioxide. This mosquito trap will then start working. TIPS: Put the trap in a dark and humid place for 2 weeks, you'll see the effect. You'll have to replace the sugar water + yeast solution every 2 weeks.