Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions

This study examined, under controlled laboratory conditions, behavioral responses of larval walleye pollock (4 to 8 mm) to various physical factors that may potentially play a role in vertical movements and distribution. Diel periodicity in vertical distribution was evident and appeared to be under...

Full description

Bibliographic Details
Main Authors: Olla, Bori L., Davis, Michael W.
Other Authors: Hatfield Marine Science Center
Format: Article in Journal/Newspaper
Language:English
unknown
Published: Inter-Research
Subjects:
Online Access:https://ir.library.oregonstate.edu/concern/articles/hh63sw351
id ftoregonstate:ir.library.oregonstate.edu:hh63sw351
record_format openpolar
spelling ftoregonstate:ir.library.oregonstate.edu:hh63sw351 2024-09-15T18:39:03+00:00 Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions Olla, Bori L. Davis, Michael W. Hatfield Marine Science Center https://ir.library.oregonstate.edu/concern/articles/hh63sw351 English [eng] eng unknown Inter-Research https://ir.library.oregonstate.edu/concern/articles/hh63sw351 Copyright Not Evaluated Article ftoregonstate 2024-07-22T18:06:05Z This study examined, under controlled laboratory conditions, behavioral responses of larval walleye pollock (4 to 8 mm) to various physical factors that may potentially play a role in vertical movements and distribution. Diel periodicity in vertical distribution was evident and appeared to be under exogenous control. During the day, with light intensity at 70 μE/m⁻²s⁻¹, larvae moved downward from the surface. As light intensity decreased during simulated evening twilight, larvae moved upward. At night, with no available light, larvae continued to swim upward, apparently the result of negative geotaxis. They remained near the surface until morning when they then began moving downward. Changes in vertical distribution occurred concomitantly with changes in activity, orientation and behavior. Formation of a vertical thermal gradient caused larvae to move upward and away from cold water. Turbulence at the surface, induced by an airstream, elicited an avoidance response and resulted in larvae moving downward. Keywords: diel periodicity, vertical migrations, light intensity, Theragra chalcogramma Article in Journal/Newspaper Theragra chalcogramma ScholarsArchive@OSU (Oregon State University)
institution Open Polar
collection ScholarsArchive@OSU (Oregon State University)
op_collection_id ftoregonstate
language English
unknown
description This study examined, under controlled laboratory conditions, behavioral responses of larval walleye pollock (4 to 8 mm) to various physical factors that may potentially play a role in vertical movements and distribution. Diel periodicity in vertical distribution was evident and appeared to be under exogenous control. During the day, with light intensity at 70 μE/m⁻²s⁻¹, larvae moved downward from the surface. As light intensity decreased during simulated evening twilight, larvae moved upward. At night, with no available light, larvae continued to swim upward, apparently the result of negative geotaxis. They remained near the surface until morning when they then began moving downward. Changes in vertical distribution occurred concomitantly with changes in activity, orientation and behavior. Formation of a vertical thermal gradient caused larvae to move upward and away from cold water. Turbulence at the surface, induced by an airstream, elicited an avoidance response and resulted in larvae moving downward. Keywords: diel periodicity, vertical migrations, light intensity, Theragra chalcogramma
author2 Hatfield Marine Science Center
format Article in Journal/Newspaper
author Olla, Bori L.
Davis, Michael W.
spellingShingle Olla, Bori L.
Davis, Michael W.
Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions
author_facet Olla, Bori L.
Davis, Michael W.
author_sort Olla, Bori L.
title Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions
title_short Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions
title_full Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions
title_fullStr Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions
title_full_unstemmed Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions
title_sort effects of physical factors on the vertical distribution of larval walleye pollock theragra chalcogramma under controlled laboratory conditions
publisher Inter-Research
url https://ir.library.oregonstate.edu/concern/articles/hh63sw351
genre Theragra chalcogramma
genre_facet Theragra chalcogramma
op_relation https://ir.library.oregonstate.edu/concern/articles/hh63sw351
op_rights Copyright Not Evaluated
_version_ 1810483453505830912