Bernhard Wessling

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 Hzor (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

(chapter in Prof. Pranges book about cranes; deutscher Text)
(graphic conclusion of crane pair composition – which individual was mating with which other individual – in a Hamburg and a neighbouring nature preserve over 10 years; pair bound and divorce, territory stability and changes)
(article describing my crane call sonagraphy experience after 5 years of performing this kind of monitoring; text in English and German)
(summary of results of 3 years crane call sonagraphy – 2000 to 2002 – in a crane-rich area in East Germany)
(text in English describing the basics of sonagraphical monitoring with evaluation and interpretation of results over 6 years; published 2003)
(text in German and partially English describing the results of sonagraphical monitoring in 2005)
(text in English describing the results of sonagraphical monitoring in 2006 and 2007)
European Crane Conference December 3 – 7, 2018 (Arjuzanx, France)
B. Wessling presentation:
(article written and published by me together with several bioacoustic research fellows from Russia about differences in crane „language“ between Japanese and Russian / Chinese red-crowned cranes recorded and analyzed by me) more data here:
a short personal text written by me in Chinese (revised by my teacher) and translated by me into English about my call recordings in Japan and Korea (DMZ) (it was a homework to be done by me for my Chinese course in June 2018)
(presentation given in a WC recovery program conference in summer 2004)
Other crane related publications
(chapter in Prof. Pranges book about cranes; deutscher Text)
Contribution to Whooping Crane Reintroduction Efforts in US
Operation Migration („OM“) was the organisation which trained the captive-reared young, freshly fledged Whooping Cranes to follow ultralight airplanes and  guided them from Wisconsin to Florida to the hibernation area from 2001 to 2016, where they became wild; here is the procedure which they follow, also mentioning my contribution (digital vocalisation recordings). After 2016, a different procedure was implemented: captive-reared young Whooping Cranes are released in Necedah National Wildlife Refuge in the neighbourhood of crane youngsters (between 1 and 4 years old) who had previously learnt the flyway and so are able to guide the fledging ones to Florida.
I had intensively worked together with OM and their founders, Bill Lishman and Joe Duff (CEO), starting with a conference in 1998 in US, where I presented my first sonagraphical work upon which I was invited to join the Whooping Crane Recovery project; so in 1999 I made my first expedition to Aransas and recorded wild whooping cranes‘ calls and other vocal expressions, a) for starting the monitoring program b) for the use in Operation Migration’s project to lead young cranes from Wisconsin to Florida. Here, in April 2000, I installed the first set of hardware on an ultralight airplane, together with Bill and Joe, and so we tested the functions which would first be used in the rehearsal project with sandhill cranes starting Sept 2000.
a young crane (~3 months) in the Hamburg Nature Preserve, only about 10 meters away from me; we looked at each other for 2 minutes
Bernhard Wessling