bioacoustic crane research and
Whooping crane reintroduction project
In the past many years, I have been active in crane protection and crane research on a national and international scale. Starting 1996, my focus changed towards crane vocalisation research, monitoring of cranes by voiceprinting (for which I developed a method). I intensively studied the common Crane (grus grus) in 3 regions in Germany, the Red-Crowned Crane in Japan and Korea (in the Demilitarized Zone between North and South Korea), and the Whooping Crane (US, in the wintering grounds in Aransas, Tx), in addition I made voice recordings of other crane species like sandhill, white-naped, black-necked cranes. The following gives links to publications resulting from this work. The biggest achievement has been to contribute clean and clear recordings of wild Whooping Cranes which had been extremely useful (and still are) for raising and flight training of Whooping Crane chicks hatched in captivity (for migration following an ultralight airplane from Wisconsin to Florida where they get released into the wild).
how do cranes produce their calls?
how to evaluate crane call recordings?
Look here to see the sequence of analysis and some examples
digital recording creates a 3D spectrogram, usually you only see 2D spectrograms and those even always between zero and 20 000 Hertz which is not helpful, I look at 2D spectrogram between 600 and 1200 Hz, or (Whooping Cranes) 600 and 1300 Hz). The 3D spectrogram will be reduced to a so-called „power spectrum“. Such spectra from various recordings in a given and in later or previous years can be compared and will show whether the calls have been made by the same pair or by different pairs, and also whether male or female have a different partner.
further links for your deeper information
Publications about Crane Calls Sonagraphy and Monitoring