Biological characteristics of Uphausia superba dan in acoustically detected aggregations near Elephant Island, Antarctica /

acoustic transponder. Discrete samples were collected at

Bibliographic Details
Main Author: Yeager, Marilyn Smith
Format: Thesis eBook
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1994.
Subjects:
Online Access:Link to OAKTrust copy
Description
Summary:acoustic transponder. Discrete samples were collected at
affected by the degree of water stratification, which in turn
aggregations and to determine the influence of physical and
and adult krill >45 mm associated with Transition Type 11
Antarctic Surface Water (AASW). On the spatial mesoscale,
Antarctica. Four areas of high krill concentrations were
biological factors on Euphausia superba distributions. The
degree of water stratification. These data suggest vertical
developmental stages between the thermocline and mixed layer
developmental stages were observed in the mixed layer of
diel migration by Euphausia superba which may have been
distances of 127-225 meters. However, some nets which fished
during the austral summer 1991-92 Antarctic Marine Living
Euphausia superba aggregations were sampled with a Multiple
Euphausia superba distributions showed a distinct separation
Euphausia superba length distribution and the proportion of
fine-scale, vertical stratification of krill with
identified with a towed l2OkHz single frequency spift-beam
individuals with the same developmental swimming skills. No
juveniles <30mm associated with WSC in shallower shelf waters
marking the mixing of Weddell Scotia Confluence (WSC) and
may influence phytoplankton population growth. On a spatial
MOCNESS study area included a major hydrographic front
Multiple Range Analysis which implies that horizontal
observed in nets which collected at one depth over horizontal
of length and developmental stages by water mass, with
Opening/Closing Net and Environmental Sensor System (MOCNESS)
patchy phytoplankton distributions or schooling with other
Resources (AMLR) survey in the vicinity of Elephant Island,
responses may be affecting krill distribution on this finer
scale. For example, Euphausia superba may be responding to
significant differences in Euphausia superba mean length were
significantly different mean lengths and proportions of
stage variability vertically and horizontally within
stratified layers of Euphausia superba were observed from the
surface to 20 meters depth. These data suggest behavioral
that varied with the diel period of the samples and the
user-designated depths to examine length and developmental
variability exists on spatial scales <125 meters.
water and the presence of Circumpolar Deep Water (CDW) on the
weakly and strongly stratified water. As many as four
west shelf and slope. There were significant differences in
within a restricted stratum grouped separately in Duncan's
Item Description:"Major subject: Oceanography".
Vita.
Physical Description:xiii, 111 leaves : illustrations, maps ; 28 cm.
Also available online.
Bibliography:Includes bibliographical references.