Feeding ecology of "Hygophum hygomii" in the Canary Islands Region (Central-east Atlantic)

Abstract

Lanternfishes are the mesopelagic community most abundant worldwide, such as Hygophum hygomii, which performs extensive diel migrations across the water column, between the surface to 1000 m of depth, interacting with plankton and micronekton at multiple depths, and generally feeding in the epipelagic layers at night. The diet composition was determined for juvenile and adult individuals, but also by sex, from samples obtained during cruises done by the B/E “La Bocaina” off the Canary Islands (Central-East Atlantic) from 1997 to 2002. A diet shift towards larger prey was evident from juveniles to adult individuals, at the time that ontogenetic changes occur in the relationship between head and body lengths, and it is probably associated to a change of habitat and/or a larger vertical migration. Hygophum hygomii showed a positive selection for copepods, but also they fed on mysids, euphausiids, decapod larvae, and other zooplankton components (such as chaetognats, amphipods, polychaetes, isopods, fishes, and gastropods larvae). Knowledge about H. hygomii ´s life story will provide information not only as a potential exploitable resource, but also for a better understanding of the pelagic ecosystem.