11/29/2022: Feed your fruit flies!
Drosophila cultures are one of the handiest things to have around when working with small invertebrates. We all may have gripes about feral fruit flies, but domesticated, flightless strains outproduce most other insects and are inexpensive to maintain. However, this value can easily be lost with improper husbandry, which surprisingly can affect fruit flies.
Adult fruit flies will feed on their culture medium, but at a certain point the number of larvae crawling about it and preventing feeding through physically blocking access to the medium or creating a pre-digested ooze that the adults don’t like becomes too much for the adults. The simplest solution: feed your adult flies!
This is relatively effortless and can be done with a chunk of fruit or jelly cup placed in the culture. You will notice a great extension in the adult lifespan (most notable in buzzatii and hydei), but also as noted by hobbyist Alex Baranowski the quality of the flies as feeders will be increased too.