Reproductive biology of the pinto guapote Parachromis managuensis (“Gunter 1867”̈) in Caño Negro - Mahogany Wetlands, El Rama, Nicaragua

Abstract

There are very few studies of reproductive biology of fish species of commercial importance in Nicaragua. That is why the main interest of this research is to study the aspects related to the reproductive biology of the guapote pinto (Parachromis managuensis) in the Mahogany Wetlands Municipal Ecological Park. Data were collected from 122 specimens captured in the study area for one year, of which 26 gonads of mature females (EMIII) were analyzed, to finally corroborate whether the species presents a single spawning or multiple spawning. It was found that the average Female and Male (F:M) ratio was 1H: 0.6M, with the average total length of this sample being 19.7 cm and 152.11 g of weight. In general, males reached larger sizes and weights compared to females. Absolute fertility (AF) was 2468 oocytes, while average fertility (Fx) was 2450 oocytes with an average diameter of 1.86 (+/- 0.10 mm): with a 95% confidence limit. The relationship between weight W and furcal length LF (W=0.39*LF^1.96), the potential model explains 84% of the variability in weight, presenting a negative allometric growth. The sexual maturity height of 50% of the population (L_50%M) was 12.2 cm in females and 17.8 cm in males. The breeding season was identified to occur in May, July, and September, with a maximum gonadosomatic index (IGS) of 4.3 in July. In addition, it was determined that the number of oocytes increases with the size of the female, estimating an increase of 166 oocytes for each additional centimeter of length. The protection of this species is recommended by reducing fishing in the spawning areas, during the reproductive season.