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Author Topic: Why do hoverflies hover?  (Read 6180 times)

Offline LeeE

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Why do hoverflies hover?
« on: 23/11/2009 15:25:26 »
What are hoverflies doing when they're just hovering in the air, apparently doing nothing useful?

Other flying insects are able to navigate and track scents while moving, and as far as I can see, just hovering in the same place would only seem to make it an easier target for predators.  However, as they've obviously still around and weren't all eaten long ago, hovering must serve some constructive purpose that outweighs the risk of being eaten.


 

Offline Don_1

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Why do hoverflies hover?
« Reply #1 on: 23/11/2009 18:09:52 »
I have always assumed they were deciding which is the best target stem for the pick of the aphids, but you're right in that other insects seem to do this 'on the wing' estimation quickly and then land. Perhaps the hoverfly, by being so diligent, manages to avoid capture by spider webs better than its rivals.
 

Offline LeeE

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Why do hoverflies hover?
« Reply #2 on: 24/11/2009 16:46:25 »
I've seen them doing it for relatively long periods of time, hovering quite a long way from any foliage.  They might hover in one place for a few seconds, then move five or six inches to one side, then up or down a bit.  This can go one for perhaps tens minutes or more, and even then, when they do fly away, they don't seem to go anywhere in particular or with any obvious sense purpose.

They must be using quite a bit of energy to do all this though, in addition to the possible increased predation risk, so I can't imagine that there's no point to it.  The best reason I can think of is that it's related to mating (perhaps trying to locate minute trace scents/pheromones) but I can't ever recall seeing any evidence of mating taking place in connection with this behaviour.
 

Offline Don_1

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Why do hoverflies hover?
« Reply #3 on: 25/11/2009 09:11:16 »
Have you also noticed they sometimes hover in front of glass, as if they are looking at their own reflection?
 

Offline LeeE

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Why do hoverflies hover?
« Reply #4 on: 25/11/2009 14:02:09 »
Where they seem to hover just seems pretty random to me, so I wouldn't be surprised to see them hovering in front of glass, especially when the observer might be looking from behind said glass ;)
 

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Why do hoverflies hover?
« Reply #4 on: 25/11/2009 14:02:09 »

 

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