Predictors and benefits of microhabitat selection for offspring deposition in golden rocket frogs

Abstract

AbstractIn many tropical frogs, offspring development and survival potentially depend on microhabitat features associated with sites that parents select for oviposition and tadpole rearing. We investigated the importance of microhabitat features in the selection of oviposition sites versus tadpole rearing sites, as well as in determining offspring survival, in the golden rocket frog, Anomaloglossus beebei. Endemic to Guyana, this species exhibits biparental care and exclusively uses phytotelmata in bromeliads for oviposition and tadpole rearing. We used model‐based inference to evaluate evidence that parents prioritize different microhabitat features in selecting phytotelmata suitable for oviposition versus tadpole rearing and that microhabitat selection can adaptively promote offspring survival. For phytotelmata in 132 bromeliads, we quantified bromeliad size, phytotelm height, leaf angle (indicative of location within the bromeliad), water volume, water temperature, dissolved oxygen concentration, and the presence/absence of potential predators and nearby conspecifics. Compared to tadpole rearing sites, oviposition sites were found in phytotelmata associated with leaves at lower angles within bromeliads, smaller water volumes, lower water temperatures, higher dissolved oxygen concentrations, and more predatory crabs. Compared with unsuccessful egg clutches, successful clutches were found in phytotelmata with lower water temperatures, higher dissolved oxygen concentrations, fewer crabs, more dragonfly larvae, and more nearby conspecifics. We conclude that the nonrandom patterns of microhabitat use for oviposition sites and tadpole rearing sites in golden rocket frogs are associated with specific environmental factors that promote offspring survival through a critical stage of the animals’ complex life cycle.