Sources of false positive detections
The major sources of false positive detections varied between frog species (Table 3). Insects caused the highest proportions of false positive detections for C.signifera, L. fletcherii, and C. parinsignifera . Calls by other frogs also caused many false positives. Other frogs returned the highest false positives forL.tasmaniensis, N. sudelli, L. raniformis , and second highest forC. signifera and L. fletcherii . False positive detections resulting from birds were high for L. dumerilli, L. peronii , andL.raniformis . Additionally, weather caused most false positive detections for L. tasmaniensis .
These false positive detection sources that generated some of the highest error – insects, other frogs, and weather – often caused high detections due to their continuous nature - as opposed to just episodic events. These categories of error routinely lasted the entire five-minute recording, hence resulting in very high false positive detections in a single file. Conversely, false positive detections from sources such as anthropogenic, aquatic, birds, nature, or other animals remained relatively low in quantity, as the intervals at which these sounds repeated were infrequent.
Table 3: False positive detections per category per frog species given as a percentage of total false positive detections of that species.