Loading...
Cloud shadows drive vertical migrations of deep-dwelling marine life
Omand, Melissa M. Steinberg, Deborah K. Stamieszkin, Karen
Omand, Melissa M.
Steinberg, Deborah K.
Stamieszkin, Karen
Abstract
Many zooplankton and fishes vertically migrate on a diel cycle to avoid predation, moving from their daytime residence in darker, deep waters to prey-rich surface waters to feed at dusk and returning to depth before dawn. Vertical migrations also occur in response to other processes that modify local light intensity, such as storms, eclipses, and full moons. We observed rapid, high-frequency migrations, spanning up to 60 m, of a diel vertically migrating acoustic scattering layer with a daytime depth of 300 m in the subpolar Northeastern Pacific Ocean. The depth of the layer was significantly correlated, with an ∼5-min lag, to cloud-driven variability in surface photosynthetically available radiation. A model of isolume-following swimming behavior reproduces the observed layer depth and suggests that the high-frequency migration is a phototactic response to absolute light level. Overall, the cumulative distance traveled per day in response to clouds was at least 36% of the round-trip diel migration distance. This previously undescribed phenomenon has implications for the metabolic requirements of migrating animals while at depth and highlights the powerful evolutionaryadaptation for visual predator avoidance.
Description
Date
2020-01-01
Journal Title
Journal ISSN
Volume Title
Publisher
Collections
Download Dataset
Files
Loading...
e2022977118.full.pdf
Adobe PDF, 1.64 MB
Rights Holder
Usage License
Embargo
Research Projects
Organizational Units
Journal Issue
Keywords
Biological Sciences Peer-Reviewed Articles, vertical migration, zooplankton, phototaxis, cloud
Citation
Advisor
Department
Virginia Institute of Marine Science