High Occurrence of Mesopelagic Fish Larvae in Epipelagic Waters Demonstrates Importance of Vertical Connectivity between Photic and Aphotic Biomes (E)
ASLO 2017 Aquatic Sciences Meeting, Honolulu, HI, February 26-March 3, 2017
Studies on early life stages of epipelagic and mesopelagic fishes are limited for many species although data on these stages is needed to better assess and monitor recruitment variability. Particularly, information on the vertical connectivity of fishes between epipelagic and mesopelagic zones is unknown. Here, we investigate the presence of mesopelagic fish larvae in the upper epipelagic or photic zone (0-100 m) of the water column in the northern Gulf of Mexico (NGoM). Summer ichthyoplankton surveys were conducted in outer continental shelf and slope waters of the NGoM in June and July 2015 using oblique bongo net tows conducted during the daytime (0700 – 1800 h). Although taxa of fish larvae common in the epipelagic zone were abundant in our collections (e.g. Carangidae [jacks], Scombridae [mackerels, tunas], Exoceotidae [flyingfishes]), larvae from families common to the mesopelagic zone were also abundant in our collections, particularly Myctophidae [lanternfishes], Gonostomidae [bristlemouths], and Sternoptychidae [marine hatchetfishes]. Lanternfishes were numerically the most dominant family present in the samples, accounting for over 20% of all larval fish collected. Lanternfishes and bristlemouths were also extremely common across our entire sampling corridor, with percent frequency of occurrence for the 48 stations sampled being above 90% and above 80%, respectively. The high occurrence of all three families of mesopelagic fishes in our surveys suggests that vertical connectivity of nekton between the photic and aphotic biomes is high; these linkages will likely play an important role in population and ecosystem level processes throughout the water column.
Meinert, C. R.; Wells, RJ David; Sutton, Tracey; Clausen, K.; and Rooker, Jay R., "High Occurrence of Mesopelagic Fish Larvae in Epipelagic Waters Demonstrates Importance of Vertical Connectivity between Photic and Aphotic Biomes (E)" (2017). Oceanography Faculty Proceedings, Presentations, Speeches, Lectures. 440.