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Résumé :
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As part of an international crane research project, we investigated food availability and diet of crane families in their breeding territories. In 1996 we determined the preferred feeding sites of six crane families by radio tracking. To analyze the availability of beetles and other invertebrates in these areas we used pitfall traps. Additional data on vegetation composition, earthworm densities, and faecal samples were collected. Analysis of 88 faecal samples revealed that the diet during the rearing period contained a higher proportion of animal food than did the winter diet. The volume of animal and vegetable remains in the faecal samples of the crane families differed significantly. Cranes fed predominantly on caterpillars (Lepidoptera, e. g. Phytomera gamma), grasshoppers (Saltatoria), and beetles (Coleoptera), with to a lesser degree on spiders (Araneida), bugs (Pentatomidae) and dipterans (Diptera). Remains of beetles (included Pterostichus spec., Calathus spec., Poecilus spec., Carabus granulatus, Harpalus aeneus, H. rufipes and Silpha tristis) were found in 62 samples (70%). We found the following maxima: one faecal sample contained the remains of 34 caterpillars, another contained seven grasshoppers and another contained
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