Distributions of <i>Euphausia Superba</i>, <i>Euphausia Crystallorophias</i>, and <i>Pleuragramma Antarcticum</i> with Correlations to Environmental Variables in the Western Ross Sea, Antarctica

<p>Antarctic krill (<em>Euphausia superb</em>a), crystal krill (<em>Euphausia crystallorophias</em>), and Antarctic silverfish (<em>Pleuragramma antarcticum</em>) are key mid-trophic level species in the Ross Sea food web that provide connectivity between primary production and the upper trophic levels. Distributions of these species were constructed from net-based and acoustic observations collected in the western Ross Sea from 1988-2004. Distributions of environmental conditions in the Ross Sea were obtained from a high-resolution circulation model (temperature, mixed layer depth, surface speed) and satellite-derived observations (chlorophyll, sea ice cover). These distributions were analyzed with a range of statistical methods to determine the extent to which species distributions are determined by environmental conditions. The results showed that each species occupies a localized habitat defined by different environmental characteristics. Antarctic krill are concentrated along the northwestern shelf break and prefer deep areas overlying warm water at depth, slow surface speeds, and proximity to the shelf break. Within this habitat, krill biomass is associated with deeper mixed layers. Crystal krill and Antarctic silverfish are concentrated in Terra Nova Bay and prefer southwesterly locations, coastal proximity, cold water temperatures, and slow surface speeds. Within Terra Nova Bay, crystal krill biomass is associated with cold temperatures and northerly latitudes. Antarctic silverfish biomass is associated with low chlorophyll. The Antarctic krill habitat off the shelf break coincides with the occurrence of Circumpolar Deep Water at depth, which is important for early life stages. The crystal krill and Antarctic silverfish habitat in Terra Nova Bay coincides with the coastal polynya, sea ice, cold water temperatures, and slow surface speeds that are needed for their early life stages. The habitat characteristics obtained for the three species provide a basis for projecting potential changes resulting from climate change. The habitats identified for the three species delineate regions of the Ross Sea that deserve focused management and inform the selection of regions for marine protected areas that support ecosystem level conservation plans.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Ocean & Earth Sciences

Year dc:date.available

2016

Author dc:creator

• Davis, Linnea Brynn

Contributors dc:contributor

• Eileen E. Hoffman
• Mark J. Butler
• Ari S. Friedlaender
• John M. Klinck
• Peter N. Sedwick

• Antartica
• Antarctic silverfish
• Correlations
• Krill
• Ross Sea
• Oceanography

Statement dc:rights

• <p>In Copyright. URI: <a href="http://rightsstatements.org/vocab/InC/1.0/">http://rightsstatements.org/vocab/InC/1.0/</a> This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).</p>

Identifier

9781369567052

OAI identifier oai:identifier

oai:digitalcommons.odu.edu:oeas_etds-1004