maria-preta-acinzentada vs maria-preta-do-sul

The Cinereous Tyrant and Hudson's Black-Tyrant are both small, dark flycatchers, but they can be distinguished by their habitat preferences and migratory behavior. The Cinereous Tyrant is more conspicuous and less migratory compared to the highly migratory Hudson's Black-Tyrant, which prefers shrubby habitats.

Observe the habitat: Hudson's Black-Tyrant is found in shrubby areas and is migratory. In contrast, the Cinereous Tyrant is more likely to be seen in less specific habitats and is more conspicuous.

The Cinereous Tyrant is more conspicuous, while Hudson's Black-Tyrant is less so and highly migratory.

Hudson's Black-Tyrant prefers shrubby habitats and migrates between the Monte and Espinal regions of Argentina and north to Bolivia and W Paraguay. The Cinereous Tyrant's habitat preferences are not detailed.