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Flies Mating

4-13-17 mating flies 042

As readers are aware, I spend a significant portion of my time outdoors examining scat, and in so doing, have discovered a family of hairy flies, Heleomyzidae, that are often present on the freshest specimens, especially in early spring and late fall. This spring I have found them mating on both coyote and bear scat.  The ardor of males is impressive – without exception the males pounce upon each and every fly of their own species they see. Repeated rejections do not appear to slow them down – just the opposite. In fact, moments after the pictured pair left the surface of a coyote scat and landed on a nearby branch, they were joined by another fly and the threesome tumbled to the ground in an attempt at a menage a trois (see inset).

Different species of flies in this family feed on different food sources. Look for them in and on carcasses, scat, compost, fungi, caves, and bird nests.

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8 responses

  1. kathy mcgreavy

    Hi Mary,

    This has nothing to do with the flies, but on WCSH 6 this morning there was a report of a sighting of a Vermillion Flycatcher. It was caught on camera on Hog Island off the Maine coast. Thought you would be interested.

    Thanks for all your blogs.

    Kathy McGreavy


    April 19, 2017 at 7:21 am

    • Wow! How I would love to see a Vermillion Flycatcher! Thanks, Kathy. Maybe there are some NC readers who are closer to Hog Island than I!

      April 19, 2017 at 2:29 pm

  2. Kate Reeves

    I re-signed up but not sure I just deleted that when I un-subscribed to the old email address. Please keep me on your list. You are WONDERFUL!!! HOPE all is well with you Mary… keep up the FANTASTIC work. Saw your Work at Montshire too. WONDERFUL! Loved the frogs. Kate Reeves


    April 19, 2017 at 7:51 am

    • Hi Kate,
      I have no control over that end of things — WordPress does. Do let me know if you aren’t getting my email posts and I’ll see if I can reach WordPress — very challenging!

      April 19, 2017 at 2:27 pm

  3. Alice Pratt

    Scientists should try to discover where all that testosterone is made? !!

    April 19, 2017 at 8:02 am

  4. Kathie Fiveash

    Once when I was watching a huge congress of yellow-spotted salamanders, which was occurring in the midst of a big gathering of wood frogs, I noticed that amorous wood frog males were clasping salamanders when they could get a hold of them. Those are powerful drives – and in all species maybe, they sometimes lead us astray!!!

    April 19, 2017 at 8:17 am

    • Hi Kathie,
      If you have my book Naturally Curious, look on page xix and you’ll see a newt enamored with a spring peeper!

      April 19, 2017 at 2:26 pm

  5. Daphne

    What an opening sentence! I had to read the whole post aloud to my husband as it was too good to keep to myself. Thank you again for showing us the many things I miss by moving on too quickly.

    April 19, 2017 at 9:12 am

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