Ant Specialization in Diet of the Narrow-mouthed Toad, Microhyla ornata, from Amamioshima Island of the Ryukyu Archipelago

Abstract

Microhyla ornata consumed numerous ants, representing 77. 1% in number and 44. 6% in volume of the diet. The toad took ants in higher proportion than were present in the surrounding environment, and therefore, could be viewed as an ant specialized predator. Ants were the most numerously consumed prey in both spring and summer, while beetles and woodlice were less frequently taken in summer. Females have a larger body and wider mouth than males, and consumed significantly larger prey in maximum size than did males. However, mean prey size, and frequencies of occurrence for all prey taxa did not differ significantly between the sexes. These results suggest that the sexes do not differ in their use of food resources despite their morphological differences.