actually, I consider retaining issues as clean as a threat! I used to artwork on the Drosophila (fruit fly) lab that made foodstuff specially for the flies, at a close-by college and right it is how we did it: components: a field a funnel or paper wrapped right into a funnel shape overlaying tape something yummy for the flies placed some foodstuff into the field (we used a million/2 pint bottles, yet you need to use exceedingly lots something with something it is taller than it truly is huge. Very ripe bananas are stable (we used the fly foodstuff that we produced for the labs) or yeast, molasses... The yeast and molasses have a extra appropriate scent than banana, yet you are able to test. place the funnel or paper funnel into the hollow, and tape all of it around. What occurs is that the flies are attracted by using the scent and have self assurance me, they discover it. they have not any situation stepping into the bottle yet they could't get out! (hotel California for fruit flies) once you have gathered them (it could take in one day or longer) fill the field with soapy water and enable it take a seat till you spot that they are not shifting. finding on what you used for foodstuff and the way lots you put in there, you're able to flush it down the rest room, we placed it down kitchen drain and used rubbish disposal.