Translator Disclaimer
1 April 2013 Sexual Differences in Post-Hatching Saunders's Gulls: Size, Locomotor Activity, and Foraging Skill
Author Affiliations +
Abstract

Various selection pressures induce the degree and direction of sexual size dimorphism in animals. Selection favors either larger males for contests over mates or resources, or smaller males are favored for maneuverability; whereas larger females are favored for higher fecundity, or smaller females for earlier maturation for reproduction. In the genus of Larus (seagulls), adult males are generally known to be larger in size than adult females. However, the ontogeny of sexual size dimorphism is not well understood, compared to that in adults. The present study investigates the ontogeny of sexual size dimorphism in Saunders's gulls (Larus saundersi) in captivity. We artificially incubated fresh eggs collected in Incheon, South Korea, and measured body size, locomotor activity, and foraging skill in post-hatching chicks in captivity. Our results indicated that the sexual differences in size and locomotor activity occurred with the post-hatching development. Also, larger males exhibited greater foraging skills for food acquisition than smaller females at 200 days of age. Future studies should assess how the adaptive significance of the sexual size dimorphism in juveniles is linked with sexual divergence in survival rates, intrasexual contests, or parental effort in sexes.

© 2013 Zoological Society of Japan
Jongmin Yoon, Seung-Hee Lee, Eun-Jin Joo, Ki-Jeong Na, and Shi-Ryong Park "Sexual Differences in Post-Hatching Saunders's Gulls: Size, Locomotor Activity, and Foraging Skill," Zoological Science 30(4), (1 April 2013). https://doi.org/10.2108/zsj.30.262
Received: 11 July 2012; Accepted: 1 November 2012; Published: 1 April 2013
JOURNAL ARTICLE
5 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top