This tale was originally published by Loret T. Setters on September 19, 2014 at the defunct national blog beautifulwildlifegarden[dot]com.
Tis the time of year when huge “bees” are flying all over the yard. They aren’t actually bees, but bumblebee mimics and they prey on the very insects they resemble. Meet a Robberfly (Mallophora bomboides), a member of the insect order Diptera. This particular species is commonly called “Florida Bee Killer” due to their preferred food choice.
This doesn’t necessarily make them a favorite of pollinator lovers.
You can’t just base an arthropod’s benefit in your beautiful wildlife garden merely by what you see in one phase of its existence. The larval stage of this insect’s lifecycle lives in the soil and are predatory on some pest soil dwellers such has grubs. Think Japanese Beetles and it give a whole new perspective and makes them a lot easier to appreciate, no?
Adults capture prey on the wing, injecting their toxic saliva to subdue it. The chemical makeup of the saliva in turn starts to liquefy the prey turning it into a digestible liquid meal. I wonder if this is how strawberry shakes mark their beginnings.
These odd-looking creatures are quite noticeable in flight due to their large size and also because they buzz when they fly. They are pretty slow in flight and gracefully land on vegetation where they grab hold of a stem or blade of grass and rest while they scan the landscape for their next meal.
I’ve seen dozens of these guys this week…a true population explosion. While I’m not thrilled with seeing them snag a bumblebee, I won’t complain about them grabbing hold of stinging yellow jackets, which tend to be a bit aggressive at a barbeque.
I also have to say that I haven’t seen any Japanese Beetles this year, so I will give the robber flies credit for keeping them in check, although the moles and armadillos might take umbrage that they aren’t getting credit.
So, the lesson here is to look beyond one habit that you may find to be unacceptable insect behavior and remember that there may also a bright lining elsewhere in the overall cycle of life. Enjoy all aspects of the creatures in your beautiful wildlife garden.