[Odonata-l] mystery egg masses

[Dennis Paulson]

Well, Kathy Biggs came through on this one; thanks! I hadn't seen  
that online photo, and now anyone who is interested can see these  
voluminous masses of eggs, presumably laid by more than one female.  
The photo she references looks very much like the egg strings that  
Judy Semroc photographed, and perhaps all Epitheca egg masses look  
much like this. Talk about putting all your eggs in one basket and  
the ensuing intensity of larval competition! Perhaps like some  
amphibian eggs, the mass of jelly (and its chemical components?)  
protects the eggs at least somewhat from predators that might home in  
on such a delectable feast.

Dennis


On Feb 9, 2009, at 2:32 PM, Kathy &/or Dave Biggs wrote:

> Here's a pix of Epitheca canis egg mass we watched being laid.
> http://southwestdragonflies.net/caphotos/basketaileggstring.jpg
> Kathy Biggs
>
> Dennis Paulson wrote:
>>
>> Hello, all.
>>
>> Has anyone out there photographed or seen clearly the egg strings  
>> of any species of Epitheca (including Epicordulia and  
>> Tetragoneuria)? I have often seen the females ovipositing, but in  
>> water too deep for me to go look at the eggs. Judy Semroc, a  
>> colleague in Ohio, has sent me photos of linear masses of eggs  
>> that look much like odonate eggs looped around floating plant  
>> stems. But the masses are up to a couple of inches wide and two  
>> feet long, with thousands of eggs in them. The eggs are elongate  
>> and don't look like any amphibian eggs I have ever seen (most  
>> North American genera). I know female Epitheca sometimes gather at  
>> single localities and lay many eggs, but this seems a bit much. If  
>> you cut across one of these "strings," you would hit about 5-10  
>> eggs. I have no idea what else they could be, and if anyone else  
>> knows, I would much appreciate the information. I can send the  
>> photos to anyone with special interest in this.
>>
>> Thanks for any help with this mystery.
>> -----
>> Dennis Paulson
>> 1724 NE 98 St.
>> Seattle, WA 98115
>> 206-528-1382
>> dennispaulson at comcast.net



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