Maturity, growth and natural mortality rate of the introduced fish Parachromis managuensis (Perciformes: Cichlidae) in the semiarid region of Brazil

Maturidade, crescimento e taxa de mortalidade natural do peixe introduzido Parachromis managuensis (Perciformes: Cichlidae) na região semiárida do Brasil

Abstract:

Aim

The present study aimed to estimate the sexual maturity, growth and mortality rates of the jaguar guapote, Parachromis managuensis, an introduced fish species in the Brazilian semiarid region.

Methods

Specimens were collected between December 2015 and November 2016, in a dam at Serra Talhada municipality, Pernambuco, where the species was abundant.

Results

In total, 520 individuals were analyzed, with total lengths (TL) varying between 23 and 240 mm. Length at sexual maturity varied between 130.87 and 140.68 mm TL (Mean = 135.78 mm TL). Through the modal progression of monthly frequency distributions, the following growth parameters were obtained according to the von Bertalanffy model: L_∞ = 341.40 mm, k = 0.840 and t₀ = -0.035 year^-1. Ages varied from 0.05 to 1.41 year, and an age at first maturity between 0.48 and 0.53 year (Mean = 0.51 year), with the largest part of the sample (72.64%) made of adult individuals. Natural mortality rates (M) were estimated from three different methods, varying between 1.53 and 3.04, with a mean of 2.27.

Conclusions

P. managuensis shows fast growth and maturation and high natural mortalities, which grants it biological advantages when compared to native species from the same trophic level in the area.

Keywords:
Jaguar Guapote; Northeastern Brazil; length-weight relationship; age structure