The Spider vs. the Robberfly  (four photos)
Spider - probably Neoscona
Robber Fly - Proctacanthus ("large robber fly")


I was out of my car on Antelope Island taking pictures of spiders and dragonflies when this obviously agitated blob fell
out of the sky and landed in the grasses.  A look through my binoculars revealed a Robber Fly with prey.  I'm surprised
the robber fly could free himself from the web attached to his wing but he kept trying to take off without much success.


I moved in for a shot and began taking pictures from different angles.  What I couldn't figure out was why the
Robber Fly was agitated and swearing a blue streak.  I was beginning to think he was fighting
something for his prey but I couldn't make out what it was.


This shot finally revealed all three:  the spider, the dragonfly and the Robber Fly.  In this photo you can see that both predators
have hold of the grass, the dragonfly and each other.  After a couple of minutes, the Robber Fly pulled away one more time
but the spider remained attached.  They all landed about four feet further east on some more grass.  They struggled a
little longer and then the Robber Fly took off , still cussing, leaving his prey and nemesis behind.

The spider immediately secured the dragonfly on a bush.  It 's my guess that this whole battle must have ensued when the
Robber Fly stole the dragonfly from the spider's web, not knowing the arachnid was attached.  What a great
event to witness.  A few minutes one way or the other and I would have missed the battle.  It was great!

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