The uropod as a proxy for total length distribution in Antarctic krill: an assessment of different models

The properties of the regression of standard length on the length of the exopodit of the telson of Euphausia superba as a method to estimate the distribution of the standard length from penguin stomach contents samples are explored. The distance between estimated and observed distributions was measu...

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Bibliographic Details
Published in:Polar Biology
Main Authors: Marschoff, Enrique Ricardo, Rombola, Emilce Florencia, Coria, Néstor Rubén
Format: Article in Journal/Newspaper
Language:English
Published: Springer
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Online Access:http://hdl.handle.net/11336/244157
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Summary:The properties of the regression of standard length on the length of the exopodit of the telson of Euphausia superba as a method to estimate the distribution of the standard length from penguin stomach contents samples are explored. The distance between estimated and observed distributions was measured with the Kolmogorov-Smirnov statistic. Sample variability was determined using resampling techniques. The ability of linear functions (Model I and II), allometric and nonparametric methods to recover the observed distributions was evaluated within samples and exchanging parameters between samples. Linear and allometric models resulted inadequate to recover the distribution, while the differences obtained with nonparametric methods fall within the bounds of sample variability, suggesting that a linear equation does not capture the relation between total and exopodit length. The use of a nonparametric regression is recommended to increase the sample size when estimating the distributions of prey lengths in stomach contents of Antarctic penguins. Fil: Marschoff, Enrique Ricardo. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina Fil: Rombola, Emilce Florencia. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Coria, Néstor Rubén. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina