What type of study you intent to do? histology ? hormonal response? in any case as you have only 6 months you need to select a fish that has cyclic spawning behaviour. If you wish to find differences between two season then U will have to have more than 6 motnhs or start at the middle of winter and end in the middle of summer.

Thanks Sir Azad. My study is on Phallostethid fish, a freshwater fish. I'm planning to do histological analysis of its gonad and describe its structure since i cannot do a 12 months sampling to see its spawning period. Morphometric analysis is also part of the study.

Dear Corral,

You can do fecundity, but you need mature samples for that. Find out the breeding season of the selected fish, if it falls within the six months which you have selected for your study you can go for fecundity. For Gonadosomatic Index and size at maturity you need the data of annual reproductive cycle. I have not any Idea of histology. But I suggest you If you are collecting your selected fish from different water bodies or different sites of one water body with around a gap of 300km you can do phenotypic stock Identification through manual morphometry and Truss morphometry by applying advanced statistical techniques like, DFA and PCA. Do not forget to take the length and weight of the fish monthly. If you have selected a species for which length weight data is not available in fish base you can easily publish a paper on length weight relationship of that fish in Journal of Applied Ichthyology. You could do a lot of work in six months but depends on the availability of your selected fish. I hope this information could help you a little. All the best for your research.

Thank you very much Sir Javaid for your suggestions. So fecundity can still be done for my study. The fish is available all year round and I have three sites for my study which includes lakes and river. I will do the phenotypic stock identification as suggested. Thank you.