"How environmental and methodological characteristics affect the sex ratio estimation in adult fish?".
Meta-analysis, sample size, study methodologies, GLMM and proportion bias.
The adult sex ratio (ASR) is the ratio of adult males to adult females in a population. ARS is the result of sex-specific processes that affect the sex ratio throughout the lives of animals, as well as the sex difference in the survival of juveniles and/or adults. Information about the reproductive biology of captured marine fish is crucial to understanding population dynamics and changes in fish life history. In addition, accurate information on the sex of the commercial catch and on the sex ratio are fundamental requirements for fisheries, for the conservation of species and for the management of various fish populations. With that in mind, the present study aims to carry out a meta-analytical approach to investigate variations in the sex ratio of adult fish using a set of data obtained from the literature. We evaluated whether there is adult sex ratio bias taking into account how different data collection methods, fish families, sample size and general aspects of biology can influence the sex ratio of adult fish. Our results did not show significant effects of the sample size, but we observed significant effects in the methods and families on the RSA variation. We found many variations in RSA studies, especially regarding sample sizes and methodologies used. The standardization of studies would allow for better analyzes and comparisons. Furthermore, our meta-analysis is important to evaluate methodological protocols in the study of ASR and to understand how ASR estimates are affected. We suggest that further studies to understand the causes of its variation and explore the implications of RSA for reproduction and population dynamics in fish.