Fruit Flies: How To Grow Flightless Drosophila Melanogaster or Hydei Fruit Fly Culture for Your Pets
Whoa! Grow Fruit Flies?
You might be asking yourself, "Why would anyone want to grow fruit flies?" If anything, most people want to kill the fruit flies that occasionally invade the home. Rest assured, these fruit flies to feed your pets are not the same as those fruit flies. There is a huge difference; these fruit flies can't fly. That's right. They are incapable of flight for one of two reasons depending on the type. There are types that have wings, yet are flightless and types that have no wings; wingless and therefore can't fly.
Poison Dart Frogs Similar to MineClick thumbnail to view full-size
Animals That Eat Fruit Flies
Just about any fish will love some fruit flies. Bettas and any kind of killifish will gorge themselves to the point of looking like they are about to pop from overeating, so use discretion. Juvenile cichlids will grow very fast when their diet is supplemented with fruit flies. Archer fish will show off their skills when fruit flies are presented in a natural way to them.
My first experience growing fruit flies was to feed my poison dart frogs. There were always more flies than my frogs could eat, so the extras were fed to my fish. Other smaller reptiles such as geckos, mantella frogs, tree frogs, small lizards, and newts will eat fruit flies as well.
Finches and other small birds will enjoy eating fruit flies. Had I known this when I was breeding Lady Gouldian and Zebra finches, I would have surely been a lot more successful.
Carnivorous plants, such as the venus fly trap, can be fed flightless fruit flies. It is very unlikely that the fruit flies will be able to hop away unlike flying and crawling insects that may escape.
Other Animals (and Plants) That Eat Fruit FliesClick thumbnail to view full-size
There are several items needed in order to culture flightless fruit flies successfully. Use your imagination and modify the setup as you see fit using similar items around the house. Just be certain that they aren't treated with chemicals as your culture will meet with an untimely death as a result.
- mason jars used for canning
- paper towels
- commercial fruit fly medium
- plastic mesh, screen, Aspen excelsior, or monafilament line
- yeast packets
- flightless fruit fly starter cultures
These are the items that I have used successfully. Some people use plastic drinking water bottles with untreated sponge in the top to stop the flies from getting out. Others use shredded wood (excelsior) instead of the plastic mesh to give the flies something to climb on. It's really up to you, but these are the basics.
Putting It Together
There are a few steps to putting it all together that should make growing your own fruit flies fun and successful.
Order some fruit fly cultures from one of the online vendors or pickup a culture or two at your local pet shop.
If using mason jars, discard the lids, but keep the ring that secures the lid on the jar. Boil the rings and the jars to destroy any bacteria on them. Set them aside to cool. Use pint jars for D. melanogaster and quart jars for D. hydei.
Pour some commercial medium into each jar. For pint jars use 1/4 cup and for quart jars use 1/2 cup. Add a pinch of yeast to each jar. Use half as much for the pint jars as you use for the quart jars. It doesn't take much. Swirl the mixture around lightly to distribute the yeast. Add an equal amount of slightly warm water to each jar (1/4 cup for pint, 1/2 cup for quart) and let the medium absorb the water.
Commercial medium is suggested since it contains mold inhibitors. There are many recipes for do-it-yourself mediums on the Internet if you choose to use one of those instead of buying ready-made medium.
Cut a piece of plastic mesh or screen an inch or so wide and 3/4 the height of the jar you're using long. Insert it into medium in the jar. It can stand straight up or lean against the side of the jar; whichever you prefer. If using monofilament line, cut a couple feet of it then coil it around your hand. Remove the coil from your hand then insert it in the jar just above the medium. Either works just as well to give the flies something to crawl on.
Cut pieces of paper towel large enough to cover the mouth of the jar with a 1/2" to 3/4" of extra all the way around. Write the date on the paper towel piece so that you know when the culture was set up.
Add ten to twenty adult flies to each jar. Place the paper towel piece over the mouth of the jar then screw the ring down over it to secure it. The flies will be kept inside and air will flow through the paper towel.
Flightless fruit fly cultures are subject to temperatures, so keep them dry and out of extreme heat or cold. Cold slows down the culture, while higher temps will either kill the culture or some say cause them to revert to producing flies capable of flight. I haven't seen this happen though I have killed two dozen jars of D. hydei by letting them get too hot.
The jars should produce for several weeks or longer. After two weeks, begin setting up new jars and add some flies from the existing jars to them. Overlapping the start and end of cultures will help to make sure you have an almost endless supply of flightless fruit flies to feed your pets.