In mid to late summer, many homes begin seeing tiny fruit flies zooming around.  They appear seemingly from nowhere, sometimes becoming numerous particularly around exposed fruit and containers of garbage or compost.  As more fresh produce hits the markets and we bring that into our houses, so along with that come the tiny eggs and even grubs of these pests that are almost universally present in the season.  Any nutrient source that is left to sit around for a few days is likely to turn into a breeding ground for these little things, and we may not even realize that we could easily be eating them in various stages of their life cycle.  'Sokay, a little extra protein never hurts.

While I've never had a major infestation, a few invariably show up around the August timeframe here.  I don't leave fruit to sit outside the fridge, but I do keep a small bucket for compost which mostly receives the used coffee grounds.  Over the years I've learned that if I do have any fruit scraps, rinds, or pits, I should *not* drop them in the regular garbage because that's turned into a primary source in the past -- easily observable during seacon by kicking the trash can, and watching several flies rise out of it.  This time, I kept any such refuse in the covered compost bucket instead, so that any fruit flies that developed in it would be trapped.  Even so, a few might escape when I opened the lid to add contents.  To partially deal with this, I kept the "electric tennis racket" handy in the kitchen and developed an interesting technique to try and intercept them before they could escape into the rest of the house.

The procedure is to remove the lid and then immediately activate the zapper and bounce it up and down flat to the rim -- it is sized about perfectly to cover the opening, and the agitation of gently tapping the bucket makes any flies present startle and fly upward.  Any that bridge across the oppositely-charged elements deliver a satisfying   *Pow!*   as they are instantly vaporized.  Interestingly, some of the young flies start out so small that they can sail right through the screen without bridging the wires, even with the margin of the tenth-inch air gap or so that the voltage could arc across, but most don't make it.  When I'm not defending my garbage, I can also keep the racket in whatever room I'm in and if I see any visitors flying by, try to wave it around in the air to intercept their flight path.  Which, I'll add, is highly unpredictable.

But with such a concentrated and confined space in the bucket this time with all those yummy nutrients present, I would have a chance to see more of the flies' life cycle as they hatched and started eating whatever was around them.  Over this period it was a mix of cherry pits in with the coffee, and let's keep in mind that fruit flies don't only eat fruit or its leavings -- in prior years they had developed in the coffee grounds without anything else present, so I knew this was one of the hot-spots -- that I'd made hotter this time by adding an actual fruit component from just the few shreds of cherry pulp still clinging to the pits.

As a little more time went by I realized that the flies weren't just magically appearing, there was a lot more going on before that.  At some point I looked into the bucket and realized that it was teeming with life!

The next phase was pupation, which was a bit harder to discern at first, but as more time went on the small specks of coffee and whatever else stuck to the lid became oddly more dense and regular.  Somehow, the larvae were making their way up the sides of the bucket, across the lid upside down, swimming in their own manufactured sticky stuff adhering them to all the surfaces, and then metamorphosing into small hard brown oval shapes, unmoving, before emerging as adult flies.  I let this whole cycle continue for a couple of weeks, as it was really interesting to see how they changed the entire environment of the bucket.  Of course here I was "breeding" fruit flies and a few of them invariably got into the rest of the house, but nothing I couldn't control.  The main annoyance is that they sound fairly similar to mosquitoes as they whiz by your ears, but at a slightly lower note of wingbeats.  I also threw together a quick-n-dirty passive fruit fly trap and set it next to the bucket, so what escaped would be locally tempted toward a different kind of doom.

Finally it was time to end this experiment, and I brought the bucket outside to dump its contents and new residents into the "back forty".  This is the state it had reached by then.  Most of the pupae were probably empty by now, having delivered their newly formed flies into what was eventually a rather exciting end every time I went to empty my coffeemaker basket [which happens about twice a day].  It's interesting how they cluster; a few larvae are visible on their way to their next phase, probably relying on feel to wiggle along while hanging over empty space, and instinctually buddying up to their neighbors for better protection and adhesion.  With the flies for the most part trapped in here, there was probably some amount of egg-laying going on as well.  There was enough energy in here to sustain a closed-loop system, but it needed to be disposed of before it got out of hand.