How To Make A Fruit Fly Collector For Feeding Pet Mantis, Frogs, etc.

The kids got a Mantis ootheca and it was recommended to feed the baby preying mantis fruit flies. Flightless fruit flies can be purchased and the medium they come with will continue to provide flies for a while. More medium can be made to start new colonies of fruit flies.

We have tons of fruit flies at the compost bin. So I thought, why not collect those. My first attempt was to place a fruit fly trap atop of the compost bin, but it only caught a few flies. Hard to compete with the tasty compost.

Inspired by the ghost vacuums of Luigi's Mansion, we built a fruit fly vacuum.

I cut the bottom off a small/medium sized Gatorade bottle, and glued a metal screen mesh across the bottom.

That bottle fit perfectly inside another hydration brand bottle with the bottom cutout.

The top of that bottle was attached to a cordless vacuum cleaner using a rubber pipe plumbing fitting adapter.

To make a funnel to increase the catch area, a hole was cut through the Gatorade bottle lid and a matching hole cut through the bottom of a plastic container. Both were glued together with hot glue (make sure to sand the mating surfaces for best adhesion for the hot glue).

Once the fruit flies are collected, the Gatorade bottle is removed and screwed into the feeding port on the enclosure we built from upcycled nut and peanut butter pretzel bites. We made a few of the Gatorade bottle fruit fly trap bottles, so usually we just swap a new one out with the old one.

The Gatorade bottle can also be used as a traditional fruit fly trap by cutting a hole in a lid and gluing a funnel into the lid. At first I used a transparent but solid funnel. I thought that I could place the Gatorade bottle over the attractant (cotton ball soaked in apple cider vinegar). I learned that fruit flies that can't reach their meal will get restless and continue walking around until they find their way out. They seem to be able to smell their way out of the funnel hole. I replaced the funnel with a mesh funnel. It allows more smell through, and makes it more difficult for the fruit flies to smell their way out and find the funnel hole. Placing the apple cider cotton ball inside the container where they can touch it keeps them happier and less restless.

Here the trap is placed over our compost bin. This is the most effective trapping method. They're trying to get to the compost in the bin, but get trapped instead.