time. It is important to note that the snippet is taken from the whitened sound and so is high-pass
filtered.
4.1.3
User parameters
The user parameters can be set by clicking the ‘Configure’ button in the Detector section.
Threshold
: The level in dB that the power-in-band must exceed the ambient noise level by for a
detection to take place. A value of 12 dB will have a high detection rate but will produce many false
positives. A value of 20 dB will detect only strong transients that are well above the ambient noise
floor.
Integration Time
: Set this to the approximate duration of the clicks of interest. For most delphinids
you would use a short averaging time, e.g., 70 µs, while for beaked whales, porpoises and NBHF
delphinids, an averaging time of 150-300 µs would be appropriate. If you are interested in detecting
any toothed whale click, you can either go with a long averaging time (which will reduce the SNR of
short transients and so give poorer detection of delphinids) or an intermediate value which will tend
to reduce sensitivity to both short and long transients but not by much.
Blanking time:
Time that must then elapse after a detection before another detection can be made.
Useful to avoid detecting echoes from a click or to prevent detecting a large number of clicks if an
animal is buzzing near the recorder.
Store Snippets:
Select to enable storage of detection snippets.
Snippet pre- and post-trigger durations
: The time with respect to the detection at which the snippet
will be taken. The snippet starts
pre-trigger
seconds before the detection and ends
post-trigger
seconds after the detection. These are both limited to 1.5 ms maximum which is more than long
