Copepods, rotifers and phytoplankton

[Chad]

Why is it necessary to maintain separation of adults from naups? It seems that it would be easier to just take the shotgun approach and sieve out some adults (200um screen) or adults and naups (50um screen then 200um screen) depending on what stage fry need fed.

 

I dont have much time think/respond now, but I wanted to answer this really quickly. Separation is necessary because the little bastids are a bit cannibalistic in intensive cultures. Production is much higher if the adults are separated from the naups. I think you could set up a culture similar to what you are talking about that would work and be automated to some extent, let me think on it and Ill get back to you.

 

Here is a source to take a look at http://www.int-res.c...47/m047p045.pdf

 

and a quote of interest

 

Heinle (1970), who found 20 to 60 % mortality per day in the first 9 stages in laboratory cultures of Acartia tonsa, suggested 'cannibalism to act as a mechanism for regulating populations when (alternative) food is scarce and densities of populations are high'.

[ctenophore]

I was afraid of that. I wonder if I blast them with food, would they still turn cannibal? Maybe the separation thing isn't as complicated as I'm picturing. I just don't want any more screens to clean if I can help it.