NEBRASKAland Magazine is dedicated to outstanding photography and informative writing with an engaging mix of articles and photos highlighting Nebraska’s outdoor activities, parklands, wildlife, history and people.
Issue link: http://mag.outdoornebraska.gov/i/846037
58 NEBRASKAland • JULY 2017 Bee Flies By Chris Helzer I nsects live surprisingly fascinating lives, and bee flies are no exception. Sure, they're flies that look and act much like bees, but that's just a tiny bit of their story. These long-nosed little insects live double lives as both pollinators and parasites. As pollinators, adult bee flies carry pollen from flower to flower on their fuzzy bodies. They are attracted to those flowers by the promise of sweet nectar, which they acquire through their lengthy proboscis. When flowers provide a platform to perch and feed from, bee flies will happily sit and eat, but their extraordinary ability to hover and feed simultaneously gives them access to even more opportunities. Much like hummingbirds and sphinx moths, bee flies can zip up to a flower, hang in the air before it, and extract its sugary reward. Scientific literature says bee flies also eat pollen, but it's unclear how they would get those sticky pollen grains through their long skinny mouth tube and into their body, and I've not yet found anyone who can explain it. It's not shocking to learn that bee flies are pollinators – they look the part, after all. What you might not guess from looking at them is that, as larvae, they are voracious parasites. There are many kinds of bee flies, and each has its own preferred target. Antlions, tiger beetles, moths, grasshoppers and bees are all subjected to parasitism by bee flies. Some bee flies hover above and flick their eggs into the burrows of ground-nesting bees, where the bee fly larvae latch onto and suck dry the bee larvae. The species of bee fly shown here is Systoechus vulgaris, which is parasitic on grasshoppers. Female grasshoppers use their ovipositors (appendages on the rear end of their body) to dig tunnels into the ground where they insert their eggs. Bee flies can sometimes be seen hovering noisily above areas where this egg-laying is taking place, chasing each other around and periodically dropping down to lay their own eggs near the nest tunnels of grasshoppers. When the bee fly larvae hatch out, they immediately burrow into the tunnels where they find and feed on the egg pods of the grasshoppers. Because of this behavior, bee flies have been credited with helping to control the size of grasshopper populations. As you're wandering the state this summer, keep an eye out for bee flies. You'll have to look closely; they're only about one-third of an inch long and look a lot like bees, but with a narwhal-like protrusion out the front. Your best chance of seeing them will be while they're hovering near or landing on flowers as adults. When you do find them, though, remember you're only seeing half of their identity. As adults, they look like sweet, fuzzy, slightly peculiar-looking bees, but in their younger days, they sucked the life out of the helpless children of other insects. ■ PHOTO BY CHRIS HELZER These little insects live double lives as pollinators and parasites.