Razorbill (Alca torda) Science Article 1
My primary aim here is to report the first large data set of live, known-sex Razorbills and to identify the degree of sexual size dimorphism in a number of body measurements. This Study is part of a wider project on mating behavior of Razorbills based on color-banded breeding pairs (Wagner 1992). Morphometric data of pairs can provide the answer to a second question, namely whether Razorbills mate assortatively by some aspect of body size.
Richard H. Wagner, The Auk 116(2):542-544, 1999