[Odonata-l] Progomphus life history

[Laura Elizabeth McMullen]

Hi all,

Basically, I am trying to estimate an intrinsic growth rate for  
Progomphus borealis populations using info I find in the literature.   
Any suggested reading or data you have gathered  that could help with  
this would be much appreciated.

If you want to know the details:

So far, in :

Poff, N.L.,et al. 2006.	Functional trait niches of North American  
lotic insects: traits-based ecological applications in light of  
phylogenetic relationships.  Journal of the North American  
Benthological Society 25(4): 730-755.

I've read that Progomphus are semi-voltine, have slow, seasonal  
development, and well-synchronized emergence.  However, in:

Corbet, P.S.  1999.  Dragonflies: Behavior and Ecology of Odonata.  
Cornell University Press.

it is suggested on page 220 that they (or some gomphids) could  
possibly be univoltine.

I've collected larvae in the field December-May and seem to see all  
instars during all months, so I'm skeptical about the seasonal  
development.

Also, as far as egg clutches go, in Corbet it is stated that some  
gomphids may lay clutches of up to 5,000 eggs, but in:

Braune, E., Richter, O., Sondgerath, D., and F. Suhling.  2008.   
Voltinism flexibility of a riverine dragonfly along thermal gradients.  
  Global Change Biology 14: 470-482.

it is suggested that more like 250 eggs/ week are layed in an about 1  
month adult lifespan (=1000 eggs).

Also, when I add up an egg "lifespan" of 13-56 days with a larval  
state that lasts 1-6 months plus a 1 month adult period, it comes out  
to about half of one year, not a year or over a year.

I'm estimating eggs to have about 22.6% mortality, the survivorship of  
larvae to be about 2.53%, and the survivorship of pre-reproductive  
adults to be about 78.2%  (Corbet).

Ok, any suggestions MUCH appreciated.  Cheers!

Laura McMullen



-- 
Laura McMullen
Department of Zoology
3029 Cordley Hall
Oregon State University
Corvallis, OR 97331

Lab:  541-737-5536