Not enough time: short-term female presence after oviposition does not improve egg survival in the emerald glass frog

• Published in: Animal behaviour 2024-07, Vol.213, p.161-171
• Main Authors: Goyes Vallejos, Johana, Sandoval Siles, José, Calero, Viky, Rodriguez, Noemi, Machado, Glauco
• Format: Article
• Language: English
• Subjects: anuran; breeding site; Centrolenidae; dehydration; egg predation; eggs; embryogenesis; embryonic mortality; females; hatching success; invertebrates; males; mortality; nearest-neighbour distance; oviposition; oviposition site; parasitism; postoviposition quiescence; predation; species
• ISSN: 0003-3472; 1095-8282
• DOI: 10.1016/j.anbehav.2024.05.008

In species exhibiting egg attendance, parents remain with their eggs, protecting them against harsh abiotic conditions, such as dehydration or drowning, and biotic conditions, such as predation, parasitism and diseases. This form of postoviposition parental care is widely observed in animals, including amphibians. Long-term egg attendance (spanning several days) is common among glass frogs, and removal experiments have demonstrated the critical role of the parent, whether male or female, in increasing egg survival. However, in a few glass frog species, females stay close to their eggs for less than 3h after oviposition. Previous studies have found that maternal presence reduces dehydration and predation despite the short duration of this attendance behaviour. In the emerald glass frog, Espadarana prosoblepon, females remain close to their eggs for less than 1.5h after oviposition. Given that the embryonic development period in this species spans an average of 25 days, our main question was whether remaining with the clutch for only 0.15% of this time is sufficient to increase egg survival. To address this question, we conducted a female removal experiment in semicaptivity and found no evidence that female presence improved egg hydration after oviposition. In a maternal commitment behavioural assay, most females promptly abandoned their clutches when subjected to a gentle disturbance and did not return to them. Lastly, a female removal experiment under field conditions revealed that clutches with and without mothers experienced similar levels of mortality, primarily caused by invertebrate predators. Through a series of experimental assays, we demonstrate that the short-term female presence in E. prosoblepon did not increase egg survival. Therefore, we argue that the postoviposition behaviour observed in this species cannot be considered parental care behaviour. Our findings challenge the assumption that the proximity of parents and their eggs is an unequivocal indicator of parental care. •Female emerald glass frogs stay with their eggs only ca. 1.5h after oviposition.•We examined whether remaining with the clutch for ca. 1.5h increases egg survival.•Female postoviposition quiescence did not increase overall egg survival.•Females' proximity to the clutch did not reduce egg dehydration or egg predation.•The proximity of adults and eggs does not necessarily indicate parental care.