Fruit flies are probably the easiest food item to culture and for sure the basic food source for captive poison dart frogs. There are a lot of recipes for culturing medium available over the Internet, and there are also many companies that sell pre-made fruit fly culturing medium. There are two species that are most often used for culturing, Drosophila melanogaster & Drosophila hydei. Both can be obtained in flightless forms so that you don't have flies flying everywhere. D. melanogaster is smaller than D. hydei and has a faster life cycle. When culturing fruit flies, it is important to be able to allow the cultures to cycle. The cycle for D. melanogaster from an egg to a fly is about 10 days. The adult flies can lay eggs for about 7 days after that. If you are going to feed them everyday, you should have a different culture to feed out of for each day until the flies in the 1st culture has had a chance to renew the cycle. That way, by the time you reach the 1st culture again, the adult flies have already been laying eggs for a week. To keep this cycle going, you are going to need to reserve some flies from each batch that is being fed out for that day, and use them to start new cultures each day until there are enough cultures to maintain the cycle. This is an ongoing process, so if your needs are small, keep the cultures small, and vice-versa. Cultures may last about a month so you will also need to start cultures to replace the ones that need to be thrown out as they get old.
This recipe for breeding flies is very easy. You will probably find hundreds of different recipes that should work, but this is one of the recipes that I am using.
* 3dl Cornflakes
* 3dl Porridge oats
* 3tsp Sugar
* 2tsp Vitamins
* 1 package 50g yeast
* (1 cap of preservative. The one I use is called Atamon.)
* About 30+ fruitflies per culture.
Mix everything with lukewarm water and allow it to rise for a while. Divide the mixture into 3 jars and drop a piece of banana in each jar. If I don't have banana it goes well with apple or some other kind of fruit. After that you put a piece of corrugated cardboard or toilet paper roll into the jar. Now it's time to let the flies in. At least 30 flies in each jar. Don't let the mixture get to dry. Somtimes you might have to mist it with a little water. A trick to get rid of odour from the culture is to pour a few drops of vinegar into the jar. Put a piece of papertowel or some kind of fabrik on top of the jar with a rubber band.
Don't forget to start new cultures as soon as there is new hatched flies in your cultures so you won't be without food for your frogs.
Known problems with fruit fly cultures: diffrent kinds of mites is always a problem with fruitflies cultures. There is always lots of tips and tricks.
The best way is to prevent the mites to develop in the jars. If you try to throw away all cultures older than 30 days it helps alot. Also try to throw away all cultures where you discover mites in even if it is full of hatched flies.
One trick that sometimes help out is to put the flies into a jar, add quite alot of calcium into the jag, add a papertowel on top with a rubberband and shake it. This powder will sufficate the mites if you let them stay into this jar for half a day or so. After this exercise you have to sift out the flies and then you use them for making new cultures from.
If you know some more tricks to get rid of the mites that seems to work, please tell us.