Kloh, J. S., C. C. Figueredo & P. C. Eterovick

Tadpole dance: the gymnastics of Ololygon machadoi larvae to feed on pollen. pp. 89-95

Abstract. A species diet offers information on its trophic level and its roles in the community. Tadpoles are known to be important components of aquatic food webs, however little is known about their feeding habits and food preferences. Tadpole ecomorphotypes have been shown to relate to their diet, but some consumed food resources are not available at preferred feeding microhabitats, such as pollen for benthic tadpoles. Pollen has high nutritive value, thus tadpoles may change their feeding behavior in order to explore it. We tested this hypothesis by offering fed or hungry tadpoles pollen on the water surface at three different depths, with or without an alternative food source. We noticed that pollen consumption decreased with increased depth, what is in accordance with optimal foraging theory, as the tadpoles have to make longer maneuvers to achieve the pollen from the bottom in deeper water. That is likely also the reason why tadpoles decreased pollen consumption when provided with alternative food on the bottom, where they usually forage. However, increased difficulty and alternative food sources did not prevent tadpoles to feed on pollen, showing that they can be flexible enough to change their feeding habits in order to opportunistically explore new nutritive food sources.

Key words. Amphibia, Anura, Hylidae, Ololygon machadoi, tadpole diet, feeding behaviour, buoyant food, optimum foraging.