Spring spawning and early nursery zone of the mesopelagic fish Maurolicus parvipinnis at the coastal upwelling zone off Talcahuano, central Chile

Abstract

Coastal upwelling areas along eastern boundary currents have been recognized for having high planktonic production. In the Humboldt Current System off South America, little is known about the reproductive strategies of mesopelagic fishes and their utilization of highly productive coastal upwelling areas for spawning and early development. In the present study, we first document the spawning and nursery area of the highly abundant mesopelagic fish Maurolicus parvipinnis in the coastal upwelling zone off Talcahuano, central Chile. Second, we propose a mechanism by which ontogenetic and diel changes in vertical distribution of the early life history stages and the utilization of the local hydrodynamics facilitates the development of the larvae of this species over the shelf and nearby slope in a highly productive environment. Our results show that M. parvipinnis spawn during early spring at mid-depth in zones of intense upwelling. Larvae hatch mostly in the spawning area located on the southern edge of the slope, and are then advected northwards along the slope or over the shelf where high larval food concentrations occur. Over the shelf, larger larvae tend to vertically migrate, spending part of the night hours in the shallower layer where the water temperature is higher, and where food is most abundant. During the day, they remain at depth where offshore transport may be decreased. Those larvae that are not retained over the shelf are advected offshore, probably in the surface Ekman layer or in association with cold filaments that usually develop off the central zone along the shelf off Talcahuano. Although information on the spawning strategy of other Maurolicus species worldwide is sparse, there are some similarities in relation to the subsurface spawning, the larval presence in nearshore waters, and the early spring spawning season in association with periods of increased food availability. The spawning strategy described herein, therefore, may be a more common feature than previously believed for Maurolicus species, especially along coastal upwelling areas in eastern boundary currents.

Larval fish distribution, growth and feeding in Patagonian fjords: potential effects of freshwater discharge

“…It is a partial spawner whose reproductive activity tends to concentrate between September and October (Leal et al 2011). Although a member of principally oceanic, mesopelagic family, lightfish seems to be associated with land masses near upwelling areas (Landaeta and Castro 2002), seamounts (Boehlert et al 1994) and fjords (Lopes 1979;Kaartvedt et al 2008). There is no information about reproductive activity of this species; however, it eggs are highly abundant during austral spring along Chile (Landaeta and Castro 2002;Bustos et al , 2011.…”

Distribucion del ictioplancton en la Patagonia austral de Chile: potenciales efectos del deshielo de Campos de Hielo Sur

“…5). Si el desove ocurre subsuperficialmente (p.e., bajo 50 m de profundidad), como lo realiza M. parvipinnis en Chile central (Landaeta & Castro, 2002), el transporte neto sería hacia el interior de los canales, incrementando los tiempos de residencia de los estados tempranos en la zona de estudio. En el presente caso, es difícil establecer la posición vertical del desove, ya que los muestreos fueron integrados, y M. parvipinnis ha mostrado una amplia variabilidad en sus tácticas reproductivas en sistemas de fiordos (Bustos et al, 2008b(Bustos et al, , 2011Landaeta et al, 2009).…”

An analysis of the impacts of climatic variability and hydrology on the coastal fisheries, Engraulis encrasicolus and Sepia officinalis, of Portugal

“…Wind, wave and current interactions largely control hydrodynamics (the boundary fl uxes, momentum and energy exchange between the atmosphere and the ocean, and within the water column) in the ocean environment (Zhang et al 2009). In fact, hydrodynamics is considered as one of the key factors for the successful recruitment of marine fi shes (Wilson et al 2008); which largely controls and infl uence current speeds, magnitude and direction, thus play the potential role in larval dispersion between offshore and onshore and to some extent inside the estuarine zone (Guisande et al 2001;Landaeta, Castro 2002). Most of the cases, wind induced phenomenon was found to have a negative impact on the studied species during their spawning and post-spawning period in the southern coast while the opposite was observed at northwestern coast.…”