Bat detectors are the most common way to identify the species of flying bats. There are distinct types of call which can indicate the genus, and variations in pattern and frequency which indicate the species. For readers not familiar with the different types of bat detector, there is further information and elsewhere. Bat detectors pick up various signals in the ultrasound range, not all of which are made by bats. To distinguish bat and bat species it is important to recognise non-bat species.