Dear colelagues, can you recommend the method description to analyse diet of jellyfish? Especially - is it possible and if so how to fix the stomachs of jellyfish and what paremeters of jellyfish (size, weight, sex) are needed?
Good question. Seems the few studies I've seen do this actually preserve the whole jellyfish for later examination in the lab.
I think it is not quite good solution, To preserve big number of jellyfish we will need too big volume tanks and too much alcohol))) In addition, if even 50 % of jellyfish (usually such percent is more, at least in fish) will be with empty stomachs it will be monkey job.
OK. Can't be mixing monkey's and jellyfish...
I'll ask around with some colleagues who do this more routinely.
Regards
I believe there are some japanese studies on Aurelia aurita. Author names eludes med for the moment ( in a meeting)
Cheers
Anders
Hi Andrey: TINRO-Center performs jellyfish analyses in sea expeditions on the regular basis. I can recommend you the article Gorbatenko, K.M., and K.V. Radchenko. 2010. New data on jellyfish (Cnidaria) ecology in the Pacific waters adjacent to Kuril Islands // Izvestiya TINRO. V. 163. P. 196-215.
Vladimir, thank you for this reference. I will check it. And do you know who is working on jellyfish now in TINRO?
Ulf Båmstedt and I did some stomach analysis on Aurelia aurita and Cyanea capillata in the 90's. Vi did fix the whole animal in 4% formaldehyde. File attached.
I do not know if it have been tried before, but to reduce the size of the sample I believe that for some species it will be possible to flush the stomach in field then fixing the fluid, or for big animals with lots of tentacles to cut off the mesoglea, flush it and fix the fluid and the tentacles .
Dear Monika! Thank you very much for this reference, I didn't see it yet. But as far as I remember one expert on jellyfish form Sankt Petersburg siad me that using formaldehyde for jellyfish fixation is not quite good.
Hi
Fixing jellyfish in formaldehyde for later identification in the lab is not good due to deformation and shrinkage, alcohol is even worse. For stomach analysis it should be ok . Check online for papers dealing with different ways to fix soft tissue as jellyfish (search for fixation or preservation).
Monica
