Details:

Personal Author:
Kendall, Arthur W. ;
Corporate Authors:
Alaska Fisheries Science Center (U.S.) ;
NOAA Program & Office:
NMFS (National Marine Fisheries Service) ; AFSC (Alaska Fisheries Science Center) ;
NMFS (National Marine Fisheries Service) ; AFSC (Alaska Fisheries Science Center) ; Less -
Description:
Walleye pollock (Theragra chalcogramma), an abundant and valuable gadid, occurs throughout the temperate and subarctic North Pacific and adjacent seas and spawns pelagic eggs in numerous defined areas within this range. These areas have different depths and hydrographic conditions. The eggs and then larvae drift with prevailing currents toward presumed juvenile nursery areas. Water temperature and currents often vary with depth, so the vertical position of the eggs can affect their rate of development, and rate and direction of drift. The specific gravity of the eggs determines their vertical position. Results of studies of the vertical distribution and specific gravity of walleye pollock eggs that have been conducted in five spawning habitats (Funka Bay, Japan; Shelikof Strait, Gulf of Alaska; Bering Sea basin; Bering Sea slope; and Eastern Bering Sea shelf are reported. I found that the specific gravity and vertical distribution of eggs varied among these spawning areas. These differences allow the eggs to reside at a depth which will minimize development time and enhance their probability of hatching in a food-rich environment. These variations in specific gravity may reflect genetic differences AMOng spawning populations.
Content Notes:
by Arthur W. Kendall, Jr. "January 2001." Also available online in PDF format via AFSC and the NOAA Central Library. Includes bibliographical references (pages 14-18).
Keywords:
[+]
Eggs
Incubation
Vertical Distribution
Walleye Pollock

Series:
AFSC processed report ; 2001-01;
Document Type:
Technical Report ;
Place as Subject:
Pacific Coast (North America) ;
Rights Information:
Public Domain
Compliance:
Library
Main Document Checksum:
[+]
urn:sha256:9b62e874d5df1ce35d5ac33cc2c6ab5782473fbd90880768125b61d2580fe8ae
File Type:

Supporting Files

• AFSC Processed Reports archive website

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