Ontogenetic vertical distribution and abundance of early life history stages of mesopelagic fishes off central California

Author(s)
Noelle M. Bowlin, Andrew R. Thompson, Juan P. Zwolinski, William Watson, and Philip A. Hastings
Abstract

To improve understanding between ontogeny and habitat use of early life history stages (ELHS; larvae and juveniles) of mesopelagic fish species, we analyzed a small set of discrete-depth samples collected by repeated 1-m2 Multiple Opening/Closing Net Environmental Sensing System tows in one location over a 24-h period in the euphotic and upper mesopelagic zones (0–600 m) off central California in 1989. Species richness and abundance were significantly higher than in Bongo net samples from 0 to 200 m at nearby stations in both the shallow (0–100 m) and deep (400–600 m) strata both day and night. The overall abundance of ELHS mesopelagic fishes was largely influenced by depth, with a detectable diel influence in some strata. Early-stage larvae occurred primarily in the shallow strata and later stages in the deep strata. Myctophidae and Bathylagidae species had similar patterns of vertical distribution within life history stages for both daytime and nighttime samples. This study shows the importance of discrete depth sampling and fine-scale taxonomic resolution for understanding the ontogenetic patterns of habitat use in ELHS mesopelagic fish species. With the increasing interest in these fishes as potential commercial resources, it is critical to pursue this type of research to better define their role in the marine ecosystem.

Pages
185-201
DOI
10.7755/PP.24.14
Supplementary material
Supplementary figures
10.7755/PP.24.14s1
Supplementary tables
10.7755/PP.24.14s2
Published online 27 November 2024