Nest-dismantling behavior of yellow-bellied prinia in mainland and island populations

Nest-dismantling behavior in birds is considered a fitness-maximizing adaptive behavior. Here, we compared nest-dismantling behavior and associated predation rates and nest characteristics in yellow-bellied prinia (Prinia flaviventris) on mainland China and the island of Taiwan during the breeding season from 2010 to 2014. Our results indicated that the proportion of individuals showing nest-dismantling behavior was higher on the island than on the mainland (29.3 vs. 0.8%). Nest-dismantling behavior was most frequent at the peak of the breeding season and mainly involved removing the upper halves of the nests and reusing the materials to construct new nests. The time taken to dismantle old nests and use the materials to build new ones was shorter than the time needed to build completely new nests. Nest predation, fidelity to the nest site, distance between old and new nests, and the costs of searching for nest materials could influence nest-dismantling behavior. Our results suggested that saving time and energy searching for new nest materials was the primary motivation behind nest-dismantling behavior in yellow-bellied prinia.