AVIFAUNA SILVESTRE DEL PARQUE DE LAS LEYENDAS, LIMA, PERÚ

Abstract

Girardinichthys multiradiatus (Meek, 1904) (Goodeidae) is a small fish, with a maximum size of 55 mm in total length, viviparous, with sexual dimorphism and belongs to a family comprising exclusively Mexican freshwater fishes. This paper discussed the proportion of sexes, length-weight relationship, gonadosomatic and hepatosomatic indexes, growth, mortality, age at first reproduction and fertility of G. multiradiatus in the lagoon of Salazar, State of Mexico during the rainy and dry seasons. At two collection points and using a bottom aquatic net we captured a total of 963 fish. The sex ratio males/females estimated during the dry season was 1.11:1 no significant difference between the sexes and 1.42:1 during the rainy season in favor of males. The rate of growth for both sexes was Isometric in the dry season and positive allometric in the rainy season; the gonadosomatic and hepatosomatic indexes and condition factors were higher for both sexes in dry season. The highest growth rate, obtained with the von Bertalanffy model for both sexes, occurred during rainy season (0.81 males and 0.69 females). Mortality for both sexes was also highest in this season. The size of first reproduction was 3.1 cm for females and 2.8 5.125 cm for males. Fertility for females was adjusted to the model F = 0.013L. G. multiradiatus is endemic to Mexico and currently faces various threats due to destruction of their habitat, so that the information obtained by this study could help to define strategies for their conservation.