Vertical Distribution of Daily Migrating Mesopelagic Fish in Respect to Nocturnal Lights
Name:
Perdana Prihartato Dissertation.pdf
Size:
13.88Mb
Format:
PDF
Description:
Perdana Prihartato Dissertation
Type
DissertationAuthors
Prihartato, Perdana
Advisors
Kaartvedt, Stein
Committee Members
Hoteit, Ibrahim
Irigoien, Xabier

Giske, Jarl
Program
Marine ScienceDate
2014-12Permanent link to this record
http://hdl.handle.net/10754/334480
Metadata
Show full item recordAbstract
The nighttime distribution of vertically migrating mesopelagic fish in relation to nocturnal light was studied during a circumglobal survey, in the Red Sea, and in a fjord at high latitude. The study was based on data derived from ship borne echo sounders (circumglobal and the Red Sea) as well as using upward looking echo sounders mounted on the bottom (Masfjorden, Norway). We also applied a numerical model for analyzing diel vertical migration patterns. The effect of the lunar cycle was the focus in studies at low latitudes, while seasonal changes in nocturnal light climate was in focus at high latitude. Lunar phase significantly affected the distribution of mesopelagic fish at the global scale and in the Red Sea. During nights near full moon, scattering layers of mesopelagic fish distributed deeper than during darker phases of the moon. At high latitude, mesopelagic fish switched its behavior along with seasonal changes in nocturnal lights. In autumn, the population of the studied fish (Maurolicus mueleri) formed separated layers. Juveniles performed normal diel vertical migration followed by midnight sinking, with midnight sinking mainly related to temperature minima and also for avoiding predators. Meanwhile the adults did not migrate vertically, reducing foraging but increasing the adult survival. From late winter to mid-Spring, interrupted ascents behavior was noted in the afternoon. Predator avoidance, satiation, and finding temperature optimum might be the reason behind interrupted ascents. At lighter nights in mid-summer, M. muelleri took on schooling behavior, likely as an anti-predator behavior permitting access to the upper waters in the absence of darkness.ae974a485f413a2113503eed53cd6c53
10.25781/KAUST-7APNU