Abundance and distribution of lantern fishes (Myctophiformes: Myctophidae) around San Pedro Martir Island, Gulf of California, during 2008

Abstract

Myctophids (Myctophidae) are a group of abundant mesopelagic fishes in the world´s oceans and are known as the main feeding resource for several high trophic level predators. Changes in abundance may be related to population size of some commercially important species that feed on them. Only two of the myctophid species reported for the Gulf of California were found in the present study: Benthosema panamense and Triphoturus mexicanus. The highest abundance and biomass of myctophids were found during the warm season (June and September), with B. panamense being the most abundant species (20,954 ind 1000 m-3), as well as the one with highest biomass (17,165.8 g 1000 m-3). B. panamese had a size mode interval of 35-40 mm, while T. mexicanus presented a size mode interval of 40-45 mm; both species had negative allometric growth. During the temperate season (February and April) B. panamense was distributed in the northwest, west, and southern regions around the island, while T. mexicanus was found in the north, west, and southern regions. During the warm season B. panamense was found distributed around the entire island and T. mexicanus was found in the west, south, and east regions of the island. These species are common around San Pedro Martir Island, with the highest values of abundance and biomass occurring during summer upwelling's.