Kapitel 5: Der Mandschurenkranich (grus japonensis)
3. Complexity
"complexity" means, how complex the calls are structured in the sonogram; this might arise from varying forms of the calls or - mainly - from the expression of many more than just one frequency at a given time during the call; for this aspect it should be understood that e.g. human voice also is composed of many frequencies expressed in parallel at a given time when speeking; in RCs, this leads to a kind of "rough" sound in comparison to Eurasian crane calls, which sound more clear (and display mainly only one main frequency at a given time);
This evaluation has been done qualitatively, as I am lacking a quantitative tool (like "pattern analysis"). The result is (ranging from 1 = simple" to 4 = "very complex"):
- J-RC m: 2.21; J-RC f 2.57: (females in Japan express almost all many overlaid frequencies at a given time)
- K-RC m: 1.91; K-RC f: 2.69: (K- and J- f seem to have a comparable complexity, but with the difference that the Japanese express more frequencies at a time, the Korean show more variability in the form)
- hence, J-RC m are calling more complex than m from mainland do; this is partially visible in some "purr" after the call tact.
