Distribution of gymnosomatous pteropods in western Antarctic Peninsula shelf waters: influences of Southern Ocean water masses

ABSTRACT Distributions of gymnosomatous pteropods, Spongiobranchaea australis and Clione antarctica , were determined at six sites along a latitudinal gradient in western Antarctica Peninsula shelf waters using vertically stratified trawls. Hydrographic data were collected at the same sites with con...

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Bibliographic Details
Published in:Polar Record
Main Authors: Suprenand, P.M., Jones, D.L., Torres, J.J.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2013
Subjects:
Online Access:http://dx.doi.org/10.1017/s003224741300065x
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S003224741300065X
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Summary:ABSTRACT Distributions of gymnosomatous pteropods, Spongiobranchaea australis and Clione antarctica , were determined at six sites along a latitudinal gradient in western Antarctica Peninsula shelf waters using vertically stratified trawls. Hydrographic data were collected at the same sites with conductivity-temperature-depth casts, and correlations of explanatory variables to gymnosome distributions were determined using statistical analyses performed in Matlab, a high level programming software to conduct numerical computation and visualisation. Explanatory variables included sampling site, latitude, longitude and depth, seawater temperature, salinity and density, Southern Ocean Antarctic Surface Water, Winter Water, Upper Circumpolar Deep Water and warm transitional waters, as well as oceanographic remote sensing data for coloured dissolved organic matter, chlorophyll a concentration, normalised fluorescence line height, nighttime sea surface temperature, photosynthetically active radiation, particulate inorganic carbon, particulate organic carbon, daytime sea surface temperature and daily sea ice concentration. Hydrographic data revealed that warmer water masses were prevalent along the western Antarctic Peninsula, and the distributions of both gymnosome species were primarily influenced by water masses, temperature, sampling site and latitude. As a consequence, distributional shifts of gymnosomes are predicted in response to the current warming trends.