계절적 특성을 알고 싶었거든요. 처음 언제 도착하는지는 알지만 얼마나 머무르는걸까요? 그게 단서가 될까요?
I wanted to know about their seasonality, what time of year, this is when they first arrive, but how long are they around for? Does that give any clues?