Productivity and Reproductive Characteristics of Silver Arowana Osteoglossum bicirrhosum (Osteoglossiformes: Osteoglossidae) at Grande lake, Putumayo basin, Peru

Abstract

Due to the importance of ornamental fishing of silver arowana, as well as, Lago Grande lake as one of the main areas for capturing baby arowanas in Peru, the present study aimed to evaluate the productivity and the biologicalreproductive characteristics of the species in the lake, which is located in the lower basin of the Putumayo River and represents an area preferred by fishermen because the important populations of silver arowana inhabiting it. Analysis of population density, biometrics, sexual maturity, spawning, fecundity, sex ratio, water level of the lake and production of baby arowana were made. The study was developed between March and July of 2012 and to implement the activities of the study was important the participation of the Association of Fishermen "Fronteras Vivas". In general, the population density extrapolated to the lake area was 1.29 fish/ha. Of these, the density of progenitors in the lake was 1.19 fish/ha. Also, male animals had total length, standard length and total weight higher than females and it was observed that the spawning period occurred in synchronization with the start of the growing of the hydrological regime. The average number of oocytes produced by females of silver arowana in the study area was 201 and the sex ratio was equilibrated. Furthermore, the study shows the capacity of production of the lake. In order to this the water lever influenced in the production of baby arowanas. It is important to continue studying the species for regulate the fishing and recover populations.

Variations in reproductive strategy of the silver Arowana, Osteoglossum bicirrhosum Cuvier, 1829 from four sub-basins of the Peruvian Amazon

“…Most of the observed differences might result from the interpretation of what is considered ‘sexual maturity’ in the Cortegano et al. () study, which was not properly defined. It is likely, when looking at their logistic curves that reach 100% only close to the maximum observed sizes, that they considered as ‘sexually mature’ female at the end of stage 2 rather than at the beginning (Fig.…”

“…Cortegano et al. () reported sizes at maturity of ~58 and 62 cm for females and males, respectively, in Lake Grande, close to Huapapa in the Putumayo. These large differences with our results from the Putumayo (47 and 43 cm for females and males, respectively) are particularly surprising, as about a third of our own sampling also came from Lake Grande.…”

“…These obviously over-estimated values, however, were likely due to the fact that the author erroneously considered individuals in vitellogenesis (stage II on gonadal maturation scale) as still immature. Cortegano et al (2014) reported sizes at maturity of~58 and 62 cm for females and males, respectively, in Lake Grande, close to Huapapa in the Putumayo. These large differences with our results from the Putumayo (47 and 43 cm for females and males, respectively) are particularly surprising, as about a third of our own sampling also came from Lake Grande.…”

“…These large differences with our results from the Putumayo (47 and 43 cm for females and males, respectively) are particularly surprising, as about a third of our own sampling also came from Lake Grande. Most of the observed differences might result from the interpretation of what is considered 'sexual maturity' in the Cortegano et al (2014) study, which was not properly defined. It is likely, when looking at their logistic curves that reach 100% only close to the maximum observed sizes, that they considered as 'sexually mature' female at the end of stage 2 rather than at the beginning (Fig.…”

Growth, survival and the histology of the digestive tract of juvenile Osteoglossum bicirrhosum (Cuvier, 1829) fed three diets containing different protein and lipid levels

“…Our knowledge of the O. bicirrhosum ecology is limited (Duponchelle et al., ), however, important for the development of its aquaculture. Several studies on its feeding habits and breeding ecology have been published in Brazil (Chaves et al., ; Mascarenhas, ; Queiroz, ), Colombia (Agudelo‐Zamora et al., ) and Peru (Torres Del Castillo et al., ; Cortegano et al., ). A recent Peruvian study has shed some light on its life traits, showing an important variability in the growth capabilities of the species between river basins (Duponchelle et al., ).…”