How to Catch & Culture Wild Fruit Flies

[Predatorhousepet]

 I had been buying fruit flies online whenever I wanted to start a fruit fly culture so that I could guarantee a particular species and size such as D. melanogaster for L1/L2 nymphs. This time I wanted winged fruit flies with the ability to fly but that was harder to find for sale than I imagined. I noticed that the wild fruit flies in my area were exactly what I needed but I had to figure out how to catch them. I was surprised how easy it ended up being.

1. First, I placed a fermented mango peel in a deli cup along with the regular culture medium. You can leave out the fruit peel if you add a little apple cider vinegar to the medium instead but fermented fruit really attracts fruit flies fast like nothing else.

2. I put an aluminum wire screen lid on the deli cup and set it outside for a few days in a place where it wouldn't be disturbed. The openings in the screen are just big enough for fruit flies to get in but excludes other larger insects. Depending on the size of the fruit flies in your area you might need to make the holes in the screen a little bigger, to do this just push a sharpened pencil or something pointy into the holes to widen them.

3. Once there was a significant gathering of fruit flies and I could see that there were maggots in the medium I quickly covered the lid with some saran wrap to trap the flies in. Then I placed the whole thing in the fridge for a minute or two to knock the flies out. Be careful not to leave them in too long.

4. Once the flies were unconscious I took off the screen lid, quickly removed the mango peel (scraping off any maggots I saw) and added some excelsior for the flies to climb on. (Work fast, they don't stay out long.) Then I sealed the cup with a new fabric lid and let the flies wake up.

The culture took off from there and I just made my second culture off the first one. Easy and basically free....with the exception of the cup & culture medium, of course. If you reuse cups and make the medium yourself the cost is just a few pennies.

 

[MantisGirl13]

That is basically how i catch my fruit flies as well, although what I did was take a bowl with vinegar and banana in it, cover the lid with plastic wrap, poke holes in the plastic wrap with a toothpick, and set it out next to the bananas. The fruit flies can come in through the holes, but then can't find their way out again. Works like a charm!

- MantisGirl13

 

[Synapze]

I'm going to use this technique to see if I can start my first culture. I'm lucky enough to have a compost bin with all the free fruitflies I want, but I hate dealing with my homemade traps. I always feel like I should be wearing a hazmat suit. ? I've never purchased fruitflies before. The only reason I haven't already tried to start a culture is because I'm concerned about the smell... and they ain't too pleasant to look at either. I try not to gross out my family any more than I feel I already do. 

3 quick questions if you don't mind:

1. Did you purchase the medium or use a recipe? 

2. Is the odor as offensive as the appearance? ?

3. Approximately what temperature range do you maintain the culture?

Thanks so much!

Steve A.

 

[Predatorhousepet]

1. Did you purchase the medium or use a recipe? 

2. Is the odor as offensive as the appearance? ?

3. Approximately what temperature range do you maintain the culture?

1. I bought my fruit fly medium from Josh's Frogs. I've been using the Hydei formulation for wild caught, hydei and melanogaster but either formulation will work, I believe their formulation is the exact same for both hydei and melanogaster

2. Fermented fruit mostly smells like rotting fruit and vinegar but that step is done outside, you remove the fruit peel before bringing it inside. The medium itself smells kinda like peanut butter and a little bit fruity, not bad at all. Once the culture is colonized it mostly smells like the medium until the very end when it starts to smell a little bit musty but the odor isn't offensive and it isn't that strong. You don't really smell it unless you put your nose right next to it. If a fruit fly culture smells really bad that means something is wrong with it and should be thrown away. Some homemade recipes use vinegar in their recipe so that medium would probably smell a bit vinegary which is fine. The smell mostly depends on what's used to make the medium.

3. Room temp is fine. Between 70 and 85°F. The cooler you keep it the slower they tend to reproduce but they go dormant if they are too cold. (You can put them in the fridge for a few minutes to make them go to sleep so they are easier to handle during transfers or feeding.)