>>4238044dubs checked
You have to observe which spots are better. Large dead trees are great for observing raptors. Some species are easier to see when it rains (like kingfishers). I think it's good to wait in a spot but staying too long there means you could miss birds in other areas. I'll usually hang around 10-15 minutes in a spot to see if there's movement, then move somewhere else (This is quite more than what a bird survey requires, which is usually two minutes of settling before starting the count)