A wetland team counted frog calls at several ponds. Each recorder was checked before it was placed beside the water. At one pond, a volunteer reported unusually few calls, although the recorder had passed its initial check. The team first considered whether fewer frogs were present. Before accepting that explanation, however, another volunteer inspected the field notes and found that heavy rain had covered the microphone during much of the recording period. The team kept the original count but marked the affected interval as unreliable. It then repeated the observation on a dry evening at the same location. The second recording contained more calls, yet the researchers did not describe this as proof of population growth. Recording conditions had changed, so the two totals could not directly measure a change in the number of frogs. The unresolved question required observations made under comparable conditions.