Black drongos introduced for pest control later threatened Guam’s native birds

In 1935, the introduction of black drongos to Rota aimed to control agricultural pests. This effort led to the birds establishing their populations, eventually spreading to Guam. However, their aggressive behavior towards native bird species has contributed significantly to declines in local avian populations, highlighting the unforeseen consequences of introducing non-native species into ecosystems.

By TOI Science Desk