Our newer ultrasonic microphones (SMM-U1 and SMX-U1) have built-in high-pass filters at 8 kHz to cut down on wind noise and other sources of low-frequency rumble. This means that any sound at frequencies lower than 8 kHz will be significantly reduced in volume or completely absent.
Our microphones are, by default, omni-directional. As such, they do not need to be aimed. For weatherproofing purposes, they should be mounted pointing slightly down (or straight down in areas of heavy wind and weather). For those models that need windscreens, they should always be present and not pushed up against the end of the microphone, so that there is an air gap between the windscreen and the microphone. Ultrasonic microphones should be mounted away from any reflective surface (trees, foliage, ground, water, walls, etc.)
This is a very difficult question to answer. The factors that determine how far a sound travels include humidity, temperature, the source volume and directionality, and surrounding clutter. Additionally, no two microphones have exactly the same sensitivity, even brand new.
This white paper discusses all of the factors involved in much greater detail.