Is there a chance for conservation breeding? Ex situ management, reproduction, and early life stages of the Harlequin toad Atelopus flavescens Duméril & Bibron, 1841 (Amphibia: Anura: Bufonidae)

Abstract

We report on our experiences with the captive management and ex situ reproduction of the Harlequin toad from Suriname (Atelopus flavescens) at the amphibian breeding unit of the Cologne Zoo. Egg deposition was stimulated by maintaining A. flavescens in a drier environment followed by a period of intensive irrigation. Here we provide for the first time an overview of the larval development from oviposition to metamorphosis, including diagnostic morphological characters according to Gosner. Eggs were arranged in strings and attached to the substrate below the water surface. Larvae hatched about five days after egg deposition and the characteristic abdominal suctorial disc developed about two days later (stages 20-21). Tadpoles are gastromyzophorous and were observed rasping algae. The average time for larval development to stage 41 was 100-130 days. Larval development appears to be dependent on water temperature with faster development at higher temperatures. Concerning color pattern in adults, we observed a slight sexual dimorphism and we were able to recognize individuals due to a constant color pattern. However, color was observed to slightly change over time.