Parental care in the long-tailed skink, Mabuya longicaudata, on a tropical Asian island

Abstract

Parental care has been reported in more than 140 species of reptiles (about 3%), but few records unambiguously demonstrate the selective value of that care. I experimentally investigated the influence of maternal attendance on survival of eggs in the long-tailed skink, Mabuya longicaudata, on Orchid Island, Taiwan, by placing sympatric reptiles, both predators and nonpredators, into nests. Without maternal care, most lizard eggs were eaten by the egg-eating snake, Oligodon formosanus. Female lizards with eggs attacked snakes more often and escaped from snakes less often than did females without eggs. Survival of eggs was lower when females were removed from clutches than when they were left in attendance. All egg loss in unprotected nests on Orchid Island was due to predation by O. formosanus. Size of snakes did not determine whether lizards abandoned egg-free nests or nests with eggs when attacked. Females that attacked egg predators had larger clutches than those that did not attack. Females recognized sympatric lizards and did not attack species that do not prey on eggs or on M. longicaudata, but recognized the predatory snake Elaphe carinata and escaped when that species entered the nest. These findings emphasize the ecological importance of an increased understanding of the function of parental care in reptiles.