Salaria pavo

(Peacock Blenny)

A Summery of the Current Collaboration Regarding Salaria pavo

BEHAVIORAL ECOLOGY AND PHENOLOGY OF SALARIA PAVO (PISCES:BLENNIIDAE) AT RIA FORMOSA

A population of the blenniid fish Salaria pavo with a peculiar set of reproductive characteristics was detected at Ria Formosa. These characteristics make it extremely interesting: i) there is a sex role reversal, females taking the initiative in courtship and competing among themselves for access to males; ii) males have two alternative reproductive tactics - parental males which defend a nest, and initial males without secondary sexual characters (head crest and anal fin glands) and which adopt a pseudofemale behavior so as to achieve parasitic fertilization of some eggs. The purpose of the present project is to study in an integrated way the hormonal, ontogenetic and behavioral aspects of this population. The aims are the following: i) to characterize the hormonal profiles of the two types of sexually active males (i.e. parental and initial); ii) to evaluate the role of the different sex hormones, particularly androgens, in the development of secondary sexual characteristics; iii) to investigate the role of the anal glands as potential producers of sex pheromones in parental males; iv) to test the existence of social control of sexual maturation and the expression of secondary sexual characters; v) to evaluate the impact of the availability of nesting substrate in the expression of the two male reproductive tactics; vi) to characterize the operational sex-ratio throughout the breeding season and to evaluate its consequences on intrasexual competition and mate choice; vii) to investigate the impact of male competition and female mate choice on the development of male secondary sexual characters; viii) to evaluate the relative reproductive success of the two male reproductive tactics. The knowledge of the reproductive biology of this species is essential, not only from an applied point of view, so as to define adequate management decisions (since this species has the status of vulnerable in Portugal), but also for ichthyological research, as it offers a model for the integrated study of the multiple aspects of teleost reproductive biology and life histories.