Age, growth and yield per recruit analysis of the pintado Pseudoplatystoma corruscans (Agassiz, 1829) in the Cuiabá River basin, Pantanal Matogrossense, Brazil

Abstract

The age and growth of the pintado Pseudoplatystoma corruscans were studied during the period from May 1994 to May 1995. The standard length ranged from 52 to 145 cm and the weight from 1.3 to 41 kg. The biometric relationship between the standard length (Ls) and total length (Ltotal) and between the total weight (Wt) and the standard length (Ls) were obtained for the species, being respectively: Ltotal = 3.296 + 1.069 * Ls and Wt = 0.00624 * Ls(3.134). The condition factor calculated monthly suggests the spawning season to be between the months of February and March. The age was estimated by counting growth rings present in the spines of the pectoral fins, and 10 age classes were detected. The mean distance of the last ring until the border of the spine suggests that the period of least growth is between July and September (dry period). Von Bertalaffy's equation describing the growth of the pintado is: Lt= 183 * [1 - exp - 0.085 * (t + 3.274)]. Total mortality was Z = 0.24 year(-1) and natural mortality M = 0.20 year(-1). As the present level of exploitation, F = Z - M = 0.04 year(-1), we conclude that the pintado stock was still underexploited in the Pantanal in the sampled period.

Fishing resources in the rio Cuiabá basin, Pantanal do Mato Grosso, Brazil

“…The decrease in total caught, changes in species ranking, and the "fishing-up" found in this study cannot be credit only to overfishing (Catella, 2001;Vaz, 2001;Mateus & Estupiñán, 2002;Mateus, 2003;Peixer, 2003;Penha, 2003;Mateus & Petrere, 2004). They seem to result from a complex interaction among overfishing, environmental degradation, changes in market preferences, and restrictive legal fishing regulations.…”

“…Because the recent data on the evaluation of stocks indicate that, with the exception of pacu (Vaz, 2001), some of the main species do not show signs of overfishing (Mateus, 2003;Mateus & Estupiñán, 2002;Mateus & Petrere, 2004;Penha, 2003), the drop in the catch from the rio Cuiabá appears to be …”

Metazoan endoparasites diversity of Pseudoplatystoma corruscans (Siluriformes: Pimelodidae) as an indicator of environmental alterations on a tropical aquatic system

“…On the several studies that have been made with several ecological and taxonomic groups, on which the reservoir impacts on the high Paraná River floodplain communities have been evaluated, qualitative and quantitative differences on the ecological communities were observed, besides alterations on the output and flow rate, reduction on the concentration of phosphorus and dissolved oxygen, low turbidity occasioned by the reservoir solid retention and alteration of the pH The fish species analyzed on this research (Pseudoplatystoma corruscans) is mainly piscivorous, feeding on a great variety of fishes (Mateus and Petrere-Jr 2004). The species feeding habitat is the factor that determines the endoparasite composition and abundance, as the hosts acquire the parasites mainly through the food ingestion (Karling et al 2012).…”

“…It is a fish with nocturne and carnivorous habits, feeding mainly on fishes and crustaceans, usually present on the deepest parts of the river. Its flesh is of excellent quality, and that's why this species has such a great economic and sport-fishing importance (Mateus and Petrere-Jr 2004).…”

Growth and mortality of Cichla spp. (Perciformes, Cichlidae) introduced in Volta Grande Reservoir (Grande River) and in a small artificial lake in Southeastern Brazil

“…It is more difficult to determine ages and growth rates in fish under tropical conditions, where the growth rings in scales, bones and otoliths are not as apparent as the winter rings in the structures of fish in temperate zones (Lizama and Vazzoler, 1993;LoweMcConnell, 1999). Therefore, the use of indirect methods for estimating growth parameters has been employed in several studies in the tropical region (Ruffino and Isaac, 1995;Lizama and Ambrósio, 2003;Mateus and Petrere Jr., 2004;Gomiero et al, 2007;Carmassi et al, 2008). These methods use data of length frequency distribution that contains information about the average length in each age group, and the position of modas associated with cohorts (Basson et al, 1988).…”