Kapitel 7: Reumés

In total, 52 different pairs (about 61% of the estimated territorial pairs) had been characterised, 29 in the first year, 38 in the 2nd and 17 in the third (bad wheather). 23 pairs were recognised from the first recordings in the second year, 11 in the 3rd from the 2nd recording serie, 8 of them (= 27.9% of the 29 pairs found in year 1) were recognised in all 3 recordings.

10 and 5 pairs, resp., had different territories than in the preceeding year, equiv to 43.5 and 45.5% of the recognised pairs, resp. They were choosing new territories up to about 15 km away from the former year's location, although shorter distances are preferred.

4 pairs were divorced. In the majority of the cases, new mates are a female, and the new pair returns to the male’s property. We have one unusual case: here, out of two neighboured pairs, one male and one female paired and took over both territories.

d) Schreikraniche / 5 Aufnahmeserien

O
n behalf of the Whooping Crane Recovery Team (WCRT, USA / Canada), recordings of calls of wild grus americana pairs were taken in 2 winters in the wintering area and in 3 summers in the breeding area of the last wild and self reproducing population of the very endangered Whooping Crane (grus americana). Both areas are vast and hard to access, especially the breeding grounds in WBNP, where each crane territory has to be accessed by helicopter. The Whooping Crane occupies territories larger than about 4 times of the size a common crane would be content with, both during spring / summer and winter.
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Hauptmenue | Vorwort | Kap 1: Bild und Ton | Kap 2: Kranicharten | Kap 3: Kennenlernen, Verhalten und Intelligenz
Kap 4: Graue Kraniche | Kap 5: Mandschurenkraniche | Kap 6: Schreikraniche | Kap 7: Resumés | Kap 8: Anhang