The protocol is simple. Watch a bird feeder for 10 minutes. To help you keep time, put your cell phone stopwatch on as you start. Record the time when each new species arrives at or near the bird feeder. There is no need to count the number of birds (just the time of the first observation of each species). The logic behind this is, on average, the more shy or rare species will arrive later, and the more common species arrive first. You can find out a bit more about the project here: http://thebdi.org/bird-feeder-project/