Condition mediates context-dependent breeding strategies and consequences

Individuals show heterogeneity in condition traits associated with reproduction and consequently may influence how they adapt to different environmental and social contexts. I tested whether a migratory Asian passerine, the hair-crested drongo (Dicrurus hottentottus), determined their breeding strategy based on both their own condition and the contexts they experience to maximize their fitness. Firstly, I showed that seasonal declining reproductive success, at least in breeding pairs that remained stable across years, was due to high-quality individuals breeding earlier and producing more fledglings, rather than an effect of deteriorating environmental condition over time. Secondly, I revealed that breeding experience (especially of males), determined the breeding performance of drongos. However, individuals did not preform better if they keep pair-bonds or when pair-bonds lasted over extended periods. Thirdly, I demonstrated that male drongos reduced their parenting care when they are more likely to find fertile extra-pair partners. Lastly, I showed that drongos were more likely to dismantle their nest after breeding if they preferred to reuse their territories in the next year. However, they did not suffer from potential territory competition in terms of losing their former territory or performing worse if they did not destroy their nest, especially when territory competition is probably weak in the population. I highlight that better understanding of how individual condition interacts with environmental and social context in determining individual breeding strategy requires the knowledge of complete individual life histories and consideration of the influence of territory quality