Just found the same thing in my pods, and being in Perth as well, hopefully we can combine our knowledge. Or drown our sorrow together. Anyway, they
could be fruit fly, Mediterranean Fruit Fly to be exact, since that is the local flavour. According to Ag Department of WA, baiting will tell you if they are present, but isnt a control measure. Spraying, either only the affeted zone, or every damn thing you can think of, are the two methods used to control them. They recommend using a range of chemicals, so organic growers can stop reading now. One of them is Rogor (or something like that), a particularly horrible one that kills everything up to birds, I would hope no-one uses that one. The other options are less nasty, but will kill most insects present, cant remember them off the top of my head. Im going to spray with
fipronil and vegemite (vegemite=protein, attracts the flies), and Im going to cover everything. Im sure some people would be horrified with this approach, Im happy with it. The only reason we have fipronil is we own a broadacre cropping farm, we use it when locust plagues come through (and very sparingly), the only other people who commonly use it are the termite guys. Will let you guys know how it goes. Fipronil isnt recommended by the Ag department, but it should be less nasty than what they advise, while still getting the job done. Plus, the cockroaches will disappear for a while!