Patrones de desplazamiento de peces nativos en el Río San Pedro (cuenca del Río Valdivia, Chile)

Abstract

Patrones de desplazamiento de peces nativos en el Río San, utilizando técnicas de marcaje-recaptura mediante pinturas elastoméricas y Pit-tags. Nuestros resultados sugieren que la mayor parte de las especies presentan desplazamientos pasivos, recorriendo distancias de hasta aproximadamente 40 km en el sentido de la corriente. También fueron frecuentes los movimientos entre riberas, aún en zonas de alta turbulencia en el río. No se evidenciaron claros movimientos activos hacia aguas arriba, pero el análisis de los resultados en conjunto con información de la estructura genética, abundancias y distribución de las especies en la cuenca, nos permite concluir que los patrones de desplazamiento de todas las especies estudiadas son relevantes para la mantención de su dinámica metapoblacional. PALABRAS CLAVE:Peces nativos, desplazamiento, marcaje-recaptura, Pit-tags, Chile. ABSTRACTThe Chilean native fi sh are characterized for having small sizes (< 30 cm). Due to this, they are generally described with a low swimming capacity and movement; nevertheless, there is no empirical study to show it. In this study we describe the movement patterns of six native species in the San Pedro River (Aplochiton taeniatus, Galaxias maculatus, Galaxias platei, Diplomystes camposensis, Basilichthys australis y Percilia gillissi) by using marking-recapture techniques with elastomeric inks and Pit tags. Our results suggest that most of the species show passive movements, crossing distances up to about 40 km in the fl ow direction. Movements between river banks were also frequent, even in zones of high turbulence of the river. Active movements upstream were note clear, but the analysis of the results altogether with information of the genetic structure, abundances and distribution of the species in the watershed, allows us to conclude that the movement patterns of all species studied are relevant for the maintenance of their metapopulation dynamics.

Echoes of a distant time: effects of historical processes on contemporary genetic patterns in Galaxias platei in Patagonia

“…), especially for species exhibiting low vagility as G. platei (Piedra et al . ). Galaxias platei females spawn their eggs on vegetated sandy bottoms near the littoral areas of lakes (Ortubay & Wegrzyn ), with eggs most likely attaching to the substrate (as occurs in other galaxiids; Charteris et al .…”

Requirements and boundary conditions for fish passes of non-sport fish species based on Chilean experiences

“…Also they perform relative long distance travels (Piedra et al 2012), consistent with a very high gene flow along large rivers (Victoriano et al 2012). …”

“…Nevertheless, they depend on connectivity along rivers to complete their life cycle and maintain genetic diversity and thus gene flow (see Victoriano et al 2012;Piedra et al 2012). Therefore, we propose that the current design paradigm of fishways developed for large migratory fish is nonapplicable for native non-sport fish, and should consider the habitat connectivity as the key concept for preservation of this highly threatened fish fauna.…”

A Community-Level, Mesoscale Analysis of Fish Assemblage Structure in Shoreline Habitats of a Large River Using Multivariate Regression Trees

“…In addition, during high flow periods, adults are infrequent in the study area but abundant downstream and in the lake (Valdovinos et al , ); whereas during the low flow season, both juveniles and adults are abundant along the entire river. This suggests partial migration for reproductive purposes (Montoya et al , ) in both directions (Piedra et al , ). The results presented here do not suggest that shorter‐term migrations from the lake were influencing species distributions, at least within the study reach, as distance from the lake outlet was not selected by any of the MRTs.…”