Journal of Ornithology

, Volume 157, Issue 3, pp 875–883 | Cite as

Sexual size dimorphism and discriminant functions for predicting the sex of Atlantic Puffins (Fratercula arctica)

  • Alexander L. Bond
  • Rebecca A. Standen
  • Antony W. Diamond
  • Keith A. Hobson
Original Article


Assortative mating is an important aspect of mate choice, especially in species where both sexes express ornamentation. Such ornaments could function as signals of individual quality and could result in individuals mating with partners of similar quality. We tested for assortative mating by measuring 63 pairs of Atlantic Puffins (Fratercula arctica) at two Canadian colonies (Gull Island, Witless Bay, Newfoundland and Labrador; and Machias Seal Island, New Brunswick), and constructed a function to predict the sex of puffins from Witless Bay. Male and female puffins have similar plumage, and both sexes have fleshy rosettes at the base of their bill, which are supposedly ornaments. We also examined changes in measurements over time in 5–30-year-old puffins recaptured at Machias Seal Island. Our discriminant function correctly predicted the sex of 88 % of puffins from Witless Bay. Overall, males were larger than females in all measurements, but within pairs, some females were larger in 4–27 % of individual measurements. We found no evidence of positive assortative mating or of assortative mating by rosette size, and rosette area did not increase with age. The importance of puffins’ rosettes as indicators of quality requires further investigation.


Atlantic Canada Atlantic Puffin Discriminant function Mate choice Sexual size differences 


Geschlechtsbezogener Größendimorphismus und Diskriminanzfunktionen zur Geschlechtsbestimmung bei Papageitauchern ( Fratercula arctica )

Assortative Paarung ist ein wichtiger Aspekt der Partnerwahl. Das gilt besonders für Arten, bei denen beide Geschlechter ornamentale Merkmale aufweisen. Solche Ornamente könnten als Signale individueller Qualität fungieren und dazu führen, dass Individuen sich mit Partnern ähnlicher Qualität verpaaren. Wir untersuchten die Frage assortativer Paarung, indem wir 63 Papageitaucherpaare (Fratercula arctica) aus zwei kanadischen Kolonien (Gull Island, Witless Bay, Neufundland und Labrador sowie Machias Seal Island, New Brunswick) vermaßen, und entwickelten eine Funktion zur Vorhersage des Geschlechts bei den Papageitauchern von Witless Bay. Bei Papageitauchern haben Männchen und Weibchen ähnliches Gefieder und beide Geschlechter tragen an der Schnabelbasis fleischige Rosetten, die vermutlich ornamentale Funktion besitzen. Außerdem betrachteten wir die zeitlichen Veränderungen der Maße bei 5–30 Jahre alten Papageitauchern, die auf Machias Seal Island wiedergefangen wurden. Unsere Diskriminanzfunktion konnte bei 88 % der Papageitaucher von Witless Bay das Geschlecht korrekt vorhersagen. Generell waren die Männchen in allen Maßen größer als die Weibchen, innerhalb der Paare waren allerdings manche Weibchen in 4–27 % der Einzelmaße größer. Es gab keine Belege für eindeutig assortative Paarung. Es gab keine Hinweise auf assortative Paarung anhand der Rosettengröße; die Rosettenfläche nahm mit dem Alter auch nicht zu. Die Bedeutung der Rosetten als Qualitätsmerkmale bei Papageitauchern bedarf weiterer Untersuchungen.



We thank D.W. Pirie-Hay, M. Ballasteros, A.K. Bowser, J. Davey, C. Jardine, K.G. Kelly, B. Martin, D. Ogden, E. Tompkins, and E. Whidden for assistance in the field. The Parks and Natural Areas Division, Newfoundland and Labrador Department of Environment and Conservation kindly granted permission for our work in the Witless Bay Ecological Reserve; the Canadian Coast Guard and Canadian Wildlife Service granted permission to work on Machias Seal Island. A. Patterson (Bold Coast Charter Company, Cutler, Maine), G.J. Robertson, S.I. Wilhelm, and Environment Canada provided logistic support. B. Pilgrim and E. Perry performed the genetic analysis, and S.L. Van Wilgenburg provided statistical advice. The Canadian Wildlife Service (permit SC 2783) and University of Saskatchewan Animal Research Ethics Board (protocol 20120008) approved this research. The Natural Sciences and Engineering Research Council of Canada and Environment Canada provided financial support. Comments from G.J. Robertson and two anonymous reviewers improved previous drafts.


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Copyright information

© Dt. Ornithologen-Gesellschaft e.V. 2016

Authors and Affiliations

  1. 1.Department of BiologyUniversity of Saskatchewan, and Environment CanadaSaskatoonCanada
  2. 2.Atlantic Laboratory for Avian ResearchUniversity of New BrunswickFrederictonCanada
  3. 3.RSPB Centre for Conservation ScienceRoyal Society for the Protection of BirdsSandyUK
  4. 4.Department of Biology, Biological and Geological Sciences BuildingWestern UniversityLondonCanada

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