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Morphometric variation in chinstrap penguins: molecular sexing and discriminant functions in the South Shetland Islands, Antarctica

  • Jaqueline Brummelhaus (a1) (a2), Victor Hugo Valiati (a2) and Maria Virginia Petry (a1)

Chinstrap penguins (Pygoscelis antarcticus) show little sexual dimorphism and sexing by direct observation can be difficult. Through molecular techniques, male and female adults were identified at Stinker Point, Elephant Island, South Shetland Islands, in the 2011–12 and 2012–13 breeding seasons. In the assessment of sexual dimorphism using morphological characteristics, males were 6.0–9.4% larger than females. From the most significant morphological measurements, a discriminant function was formulated that classified 80.6% of the birds correctly. In addition, our data on bill length and depth were compared with those in the literature to evaluate sexual dimorphism between different breeding locations and to test the performance of the discriminant function. There were no differences in sexual dimorphism between breeding locations. However, the discriminant function should be used with caution because some penguins may be misclassified. Therefore, when there is doubt about the accuracy of morphometric approaches, application of molecular sexing techniques is recommended.

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Amat, J.A., Viñuela, J. & Ferrer, M. 1993. Sexing chinstrap penguins (Pygoscelis antarctica) by morphological measurements. Colonial Waterbirds, 16, 213215.
Bertellotti, M., Tella, J.L., Godoy, J.A., Blanco, G., Forero, M.G., Donázar, J.A. & Ceballos, O. 2002. Determining sex of magellanic penguins using molecular procedures and discriminant functions. Waterbirds, 25, 479484.
Blondel, J., Perret, P., Anstett, M.C. & Thebaud, C. 2002. Evolution of sexual size dimorphism in birds: test of hypotheses using blue tits in contrasted Mediterranean habitats. Journal of Evolution Biology, 15, 440450.
Calabuig, C.P., Green, A.J., Ferrer, M., Muriel, R. & Moreira, H. 2011. Sexual size dimorphism and sex determination by morphometric measurements in the coscoroba swan. Studies on Neotropical Fauna and Environment, 46, 177184.
CCAMLR. 2004. CCAMLR ecosystem, monitoring program, standard methods. Hobart, TAS: Commission for the Conservation of Antarctic Marine Living Resources. Available at:
Costantini, V., Guaricci, A.C., Laricchiuta, P., Rausa, F. & Lacalandra, G.M. 2008. DNA sexing in Humboldt penguins (Spheniscus humboldti) from feather samples. Animal Reproduction Science, 106, 162167.
Davis, L.S. & Speirs, E.A. 1990. Mate choice in penguins. In Davis, L.S. & Darby, J.T., eds. Penguin biology. San Diego, CA: Academic Press, 377397.
De Leon, A., Fargallo, J.A. & Moreno, J. 1998. Parental body size affects meal size in the chinstrap penguin (Pygoscelis antarctica). Polar Biology, 19, 358360.
Genovart, M., McMinn, M. & Bowler, D. 2003. A discriminant function for predicting sex in the Balearic shearwater. Waterbirds, 26, 7276.
González-Solís, J. 2004. Sexual size dimorphism in northern giant petrels: ecological correlates and scaling. Oikos, 105, 247254.
Griffiths, R. 2000. Sex identification in birds. Seminars in Avian and Exotic Pet Medicine, 9, 1426.
Griffiths, R. & Tiwari, B. 1993. The isolation of molecular genetic markers for the identification of sex. Proceedings of the National Academy of Sciences of the United States of America, 90, 83248326.
Harris, C.M. 2006. Wildlife awareness manual: Antarctic Peninsula, South Shetland Islands, South Orkney Island. Wildlife information publication No. 1. Prepared for the UK Foreign and Commonwealth Office. Cambridge: Environmental Research and Assessment, 139 pp.
Hart, T., Fitzcharles, E., Trathan, P.N., Coulson, T. & Rogers, A.D. 2009. Testing and improving the accuracy of discriminant function tests: a comparison between morphometric and molecular sexing in macaroni penguins. Waterbirds, 32, 437443.
Jakubas, D. & Wojczulanis, K. 2007. Predicting the sex of Dovekies by discriminant analysis. Waterbirds, 30, 9296.
Marchant, S. & Higgins, P.J. 1990. Handbook of Australian, New Zealand and Antarctic birds, vol. 1, Part A. Oxford: Oxford University Press, 1408 pp.
Mariano-Jelicich, R., Madrid, E. & Favero, M. 2007. Sexual dimorphism and diet segregation in the black skimmer Rynchops niger . Ardea, 95, 115124.
Minguez, E., Fargallo, J.A., de Leon, A., Moreno, J. & Moreno, E. 1998. Age-related variations in bill size in chinstrap penguins. Colonial Waterbirds, 21, 6668.
Moreno, J., Bustamante, J. & Viñuela, J. 1995. Nest maintenance and stone theft in the chinstrap penguin (Pygoscelis antarctica) 1. Sex roles and effects on fitness. Polar Biology, 15, 533540.
Poisbleau, M., Demongin, L., van Noordwijk, H.J., Strange, I.J. & Quillfeldt, P. 2010. Sexual dimorphism and use of morphological measurements to sex adults, immature and chicks of rockhopper penguins. Ardea, 98, 217224.
Polito, M.J., Clucas, G.V., Hart, T. & Trivelpiece, W.Z. 2012. A simplified method of determining the sex of Pygoscelis penguins using bill measurements. Marine Ornithology, 40, 8994.
Quintana, F., López, G.C. & Somoza, G. 2008. A cheap and quick method for DNA-based sexing of birds. Waterbirds, 31, 485488.
Serrano-Meneses, M.A. & Székely, T. 2006. Sexual size dimorphism in seabirds: sexual selection, fecundity selection and differential niche-utilisation. Oikos, 113, 385394.
SPSS. 2009. SPSS base 10.0 user’s guide. Chicago, IL: SPSS, 548 pp.
Storer, R.W. 1966. Sexual dimorphism and food habits in three North American accipiters. Auk, 83, 423436.
Valenzuela-Guerra, P., Morales-Moraga, D., González-Acuña, D. & Vianna, J.A. 2013. Geographical variation of gentoo penguin (Pygoscelis papua) and sex identification: using morphometric characters and molecular markers. Polar Biology, 36, 10.1007/s00300-013-1389-2.
Williams, T.D. 1995. The penguins. Oxford: Oxford University Press, 309 pp.
Zavalaga, C.B. & Paredes, R. 1997. Sex determination of adult Humboldt penguins using morphometric characters. Journal Field Ornithology, 68, 102112.
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Antarctic Science
  • ISSN: 0954-1020
  • EISSN: 1365-2079
  • URL: /core/journals/antarctic-science
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