They seem to be mean little guys. They eat other insects including flies. But, aside from being part of the balance Nature supports, they also keep pests under control.
Robber Fly-Efferia aestuans male with Striped Deer Fly-Chrysops vittatus. The image is a little brighter if you click it.
The deer fly can spread a stomach virus to animals and occasionally to humans so E. aestuans is doing us a big favor. Besides the virus deer flies have a nasty little bite.
Stephen Gingold Nature Photography Blog 
That’s a nice crisp action shot.
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Actually it sat there for a while and I managed four shots before this one. I guess maybe they hold still until the prey stops struggling.
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I’m all for a few less deer flies! Nice catch, for both you and the robber fly. 😉
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Thanks, Eliza. And thanks, robber! 🙂
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Kudos on this fella, but my goodness, it looks frightening!
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Thanks, Donna! Thank goodness they aren’t the size of elephants. 😀
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😅 👍
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I’ve had the dubious pleasure of meeting the deer fly, and those critters are mean. The robber fly is welcome to as many as it can catch.
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There is a spot in the North Quabbin area that I visit often and if I forget to dab my Picaridin they swarm all over me. I wish I had a robber fly body guard that travels with me.
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So the robber fly is doing a great job and protects nature on his own way.
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Yes, a very useful insect and good yard citizen. 🙂
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Sounds like it does an important job! We don’t get deer flies here but we can get horseflies and they have a mean bite!
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We have horse flies here also and yes, they have fangs 🙂 and their bites are painful.
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Not really a ‘like’ more a ‘sympathy’ gesture!
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Hmmm… just yesterday I was photographing a large insect that appeared to be some sort of fly but I had no clue what and still haven’t done any research, but I wonder if it might be one of these. Will have to compare photos. I agree, it certainly does look like a mean little guy.
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Fortunately they are not fond of our flesh like horse flies. I hope you get an ID. Have your tried iNaturalist? It isn’t always 100% accurate but usually gets you close.
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