Feeding and nutritional ecology of the edible sea urchin Loxechinus albus in the northern Chilean coast Ecología nutricional y alimenticia del erizo comestible Loxechinus albus en el norte de Chile
subject: Loxechinus, assimilation efficieney, dieta, eficiencia de asimilación, natural diet, selectividad trófica, trophic selectivity
description: The red sea urchin Loxechinus albus, an economically important species oceurring along the Chilean littoral benthic systems, has been heavily exploited by artisanal fisheries in recent decades. However, basic knowledge of its trophic biology is still scarce. Studies of this kind are critical to the successful development of farming techniques as an alternative to the harvest of natural populations. The aims of this study were to quantify the composition of L. albus' natural diet, to determine the assimilation efficieney of the most important dietary components, and to experimentally examine the species' trophic selectivity. Adult and juvenile specimens were sampled in spring 1993 and summer, fall and winter 1994 from the shallow subtidal zone of Iquique, northern Chile. Neither juveniles ñor adults showed significant seasonal differences in dietary composition. The main Ítems in the diet were the green alga Ulva sp. for juveniles and the kelp Lessonia sp. for adults. In adults, assimilation efficieney (as percentage of the total organic matter ingested) was not significantly different among individuals that consumed Lessonia sp. (48.7 %), Ulva sp. (44.6 %) and Macrocystis (38.1 %), whereas in juveniles assimilation efficieney was significantly higher for individuals fed on the chlorophyte Ulva sp. (55.4 %), followed by Lessonia sp. (35.0 %) and Macrocystis (25.5 %). These results suggest that L. albus undergoes an ontogenetic shift in the diet, consisting of a differential foraging strategy between juveniles and adults.El erizo Loxechinus albus (Molina, 1782) es un recurso de gran importancia económica en los sistemas bentónicos costeros, y que se encuentra bajo una fuerte presión de explotación. Sin embargo, los antecedentes sobre diversos aspectos básicos de su biología trófica son aún escasos. Estudios de esta naturaleza son importantes en razón a que constituyen la base para el desarrollo de técnicas de cultivo exitosas, alternativa a la explotación de poblacion…
creator: F. PATRICIO OJEDA, SOLANGE J GONZÁLEZ, CRISTIAN W CÁCERES
source: Revista Chilena de Historia Natural
publisher: BMC
date: 2008
relation: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2008000400010
coverage: Botany, Zoology