[Odonata-l] Sympetrum egg leaving female

[Dennis Paulson]

Re the laying of eggs by dragonflies in the hand, I have had this  
happen many, many times with female libellulids (I can't recall about  
corduliids or gomphids, the other major groups of exophytic  
ovipositors). I have always thought it was just a reflex action to  
continue laying once they had started. I have held individuals in my  
hand for some time, and the eggs just keep coming out. The same thing  
often happens in the envelope when a specimen is retained alive for a  
while. It seems counterproductive to me that they would lay eggs when  
taken away from the water, as that would have no positive  
consequences. Don't butterflies do the same thing, continuing to lay  
eggs when in the hand, even when not on their host plants?

If the female had not been caught, she would presumably have gone on  
to lay eggs, so it's not as if she is laying eggs just because she  
was caught ("reproduce before you die"). If she hadn't been just  
ready to lay eggs, I don't think she would have (the majority of  
females I catch do not lay eggs).

I don't know if the weight of the eggs that a female might lay just  
before or when she was caught would represent enough of her body  
weight to have a real effect on her ability to escape. Now if she  
could flick the eggs in the eyes of her captor . . . .

One more thing. I don't think endophytic ovipositors continue to lay  
eggs when captured. I don't think I have ever found an egg in an  
envelope with a female damselfly or aeshnid.
-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net

On Feb 10, 2009, at 11:39 AM, MARIE/KEVIN HEMEON wrote:

> I saw the dropping of eggs with a Somatochlora tenebrosa. In  
> addition to a last ditch effort to pass on the genes, could it be  
> an escape mechanism? Lighten the load in case an opportunity for  
> escape presents itself?


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