"观察研究野鸟" can be translated into English as "observing and studying wild birds".
Alternatively, depending on the context and the level of formality, you could also say:
"Conducting observations and research on wild birds" (more formal, often used in academic or scientific contexts).
"Observing and investigating wild birds" (emphasizing the investigative aspect).
The simplest and most commonly used version is "observing and studying wild birds."