Nightmigrants.com 

HomeBird picsRecorded CallsEquipment & TechniquesContact MeLinks

Finding Cuckoo Calls using Ravenlite

The Thrush detector program from Old Bird does not effectively scan for calls at frequencies below 2 kHz.  To find cuckoo and other birds with calls below 2 kHz such as American Bittern, I manually scan the sound file using Ravenlite. For a sound file saved in 44,000 kHz sampling rate, 16 bit, .wav format, Ravenlite will show about 1 minute of time per screen.  For a sound file saved in 22,050 kHz sampling rate, 16 bit, .wav format, Ravenlite will show about 2 minutes of time per screen.  I record and save my sound files in 1 hour increments.  To manually look through an hour of sound takes me about 8-9 minutes (if I'm just looking at the low frequency area and not stopping to zoom in and look at other interesting calls above 2 kHz).  My current PC is a Pentium 4 purchased in early 2004.  I would think that scanning the same file with a computer equipped with Pentium Duo Core processor would take even less time.

             Yellow-billed Cuckoo call sequence recorded on 5-26-06.  No soundfile linked.

               Yellow-billed Cuckoo call sequence recorded on 5-27-06.  No soundfile linked.

martinap2@verizon.net