Population dynamics of Mylossoma albiscopum (Characiformes: Serrasalmidae) in the Ucayali River

Abstract

Mylossoma albiscopum show high levels of fishing landing in Pucallpa city (Ucayali Region, Peru). Nevertheless, information available about the population and reproductive parameters and exploitation of this species, is limited. Reason that motivated the development of this research, whose basis was the analysis of information on length frequencies and biological records in the Ucayali River at 2011–2019, moreover, to attain reproductive parameters, 11005 individuals were analyzed and sampled from the main fish landing sites of Pucallpa city. Females reach the mean length at first gonadal maturity at 14 cm (1.13 years) and males at 13.6 cm (1.29 years) of total length, respectively. The equations for theoretical growth according to the von Bertalanffy are defined by Lt = 33.81*(1 − e−0.38(t−0.42)) for unsexed, Lt = 32.26*(1 − e−0.38(t−0.43)) for females and Lt = 29.93*(1 − e−0.38(t−0.44)) for males; these results allow inferring that this species has fast growing and maximum age at 7.46. Exploitation rate was estimated to be 0.61 years−1, expressing overfishing values, which would involve generating a Fishery Management Plan for its conservation and sustainability in the Ucayali Region.