Oviposition Site Selection of the Toad, Melanophryniscus rubriventris in an Unpredictable Environment
GOLDBERG, JAVIER; QUINZIO, SILVIA; VAIRA, MARCOS
CANADIAN JOURNAL OF ZOOLOGY
NRC Research Press
Lugar: Canadá; Año: 2006 vol. 84 p. 699 - 699
Oviposition-site selection plays an important role in the reproductive success of amphibians. In unpredictable environments where resources vary within a season, amphibians should select oviposition sites using parameters that can be easily evaluated, or spawn in several ponds to increase offspring survival. Melanophryniscus rubriventris (Vellard, 1947) uses shallow ephemeral ponds in an unpredictable montane-forest environment. During 40 consecutive days, we surveyed potential spawning sites and measured several biotic and abiotic factors to determine if any of these factors influenced breeding-site selection. We also described the spawning behavior of this species. Water temperature and pond level (flooded or not) were significant predictors of whether a pond was used or not. Warmer ponds would permit accelerated development of larvae in habitats where ponds are ephemeral and their presence unpredictable. Because of the short and unpredictable hydroperiods, it will be better to select a pond full of water instead of evaluating other pond characteristics that can be very variable. Mating pairs spread several egg masses to different sites but in the same pond. This behavior is likely a consequence of pairs avoiding interactions with intruding males and not as a strategy to enhance offspring survival.