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.
Wildlife Acoustics, Inc.
3 Mill and Main Place, Suite 210
Maynard, MA 01754-2657 USA
+1 (978) 369-5225
+1 (888) 733-0200