Western marsh harrier (Circus aeruginosus)
Also Eurasian marsh harrier

The western marsh harrier (Circus aeruginosus) is a large harrier, a bird of prey from temperate and subtropical western Eurasia and adjacent Africa.

This species has a wide breeding range from Europe and northwestern Africa to Central Asia and the northern parts of the Middle East. 

accipitrinus Latin accipitrinus hawk-like (accipiter: hawk).
In both Latin and Greek, the root of the word "circus" means "ring" or "circle". The Latin word circus comes directly from the Greek word κίρκος (kírkos), which also means "circle" or "ring". This etymology describes the shape of the ancient Roman arenas and the modern performance spaces where circuses are held. 

Aeruginosus is a Latin adjective meaning "covered with verdigris," "rusty," or "bluish-green"; derived from aerūgo (copper rust/verdigris), it describes the green patina on copper.