Taxonomic and geographic variation in oviposition by tailed frogs (Ascaphus spp)

Tailed frogs (Ascaphus spp.) oviposit in cryptic locations in streams of the Pacific Northwest and Rocky Mountains. This aspect of their life history has restricted our understanding of their reproductive ecology. The recent split of A. montanus in the Rocky Mountains from A. truei was based on molecular differentiation, and comparisons of their ecology are limited. Our objectives were to provide a range-wide summary of information on Ascaphus oviposition, compare some aspects of the reproductive ecology of the 2 species, and examine geographic variation in their reproductive traits. Reproductive ecology of the 2 species differed. Ascaphus truei had smaller clutches, oviposited later in the summer, and had a longer duration of oviposition than A. montanus. A greater number of communal oviposition sites were attributed to A. montanus. These ecological differences support the recent taxonomic revision of Ascaphus and suggest that different management strategies may be necessary for each species where conservation is a priority.