A Comparison of Structures Related to Foraging in Two Closely Related Gulls: Larus Leucophthalmus and L. Hemprichii

Storer, R. W. & Goodman, S. M. 1988. A comparison of structures related to foraging in two closely related gulls: Larus leucophthalmus and L. hemprichii. Ostrich 59: 145-149. The closely related White-eyed and Sooty Gulls (Larus leucophthalmus and L. hemprichii) are widely sympatric in the Egyptian Red Sea. Morphological differences in skeletal proportions which appear related to differences in foraging methods are the relatively longer neck, bill, wing tips, and Crista fibularis of the tibiotarsus in the White-eyed Gull and the relatively wider gape, longer tarsometatarsus, and shorter middle toe in the Sooty Gull. Males of both species have relatively longer bills and wider gapes than the respective females. There are no significant differences between the sexes of either species in wing or leg proportions, or in the total lengths of these elements as a percentage of the cube root of the products of three cranial measurements. We suggest that these interspecific morphological differences are related to differences in foraging methods. © 1988, Taylor & Francis Group, LLC.