I search into Articles and there is no detailed information for age at maturity calculation protocols, and I didn't calculate GSI because my sampling wasn't monthly basis. So Is that make any trouble in that calculation?
Hi Milad,
you do not have to calculate GSI to estimate age at maturity. You need just to know the age of every fish you sampled (in months or in years, depending on life expectancy) and physiological status (adult, mature vs immature). Then you need to calculate a sigmoid curve describing changes in percentage of adults in the sample with age (beginning from zero in juveniles, eventually it will be 100% when all fish become adults). The age when this curve crosses 50% is age at maturity.
Best regards,
Vlad
Hi, you need to have data on various age group and corresponding ovary maturation condition data. There are number of papers on estimating first maturity, few references
http://www.dfw.state.or.us/mrp/publications/docs/Info200904_YlwEyeRF_Maturity.pdf
http://www.fishbase.org/manual/Fishbasethe_MATURITY_table.htm
length at first maturity
Qasim, S. Z., 1973. An appraisal of the studies on maturation and spawning In marine teleosts from the Indian waters. Indian J. of Fish., 20 (1): 166-181.
- Badges
- Science topic
- Similar topics
- Biological Science
- Zoology
- Ichthyology
- Vertebrates
- Fish