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Résumé :
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Most of the original habitat on the Comoros was forest, but humans brought about important modifications. Presently, fifty-four terrestrial birds are resident. Endemism is as follows: Grande Comore is the richest (at species and at subspecies level); Moheli is Grande Comore's satellite, sharing some endemism; Mayotte is a smaller centre of endemism; Anjouan is the poorest. Habitat choice and abundance were essentially obtained from standardised point-transect counts. Habitat preferences: (i) Grande Comore: Otus pauliani, Humblotia flavirostris and Zosterops mouroniensis are restricted to high altitude; most other endemics reach highest densities in the remaining undisturbed forests but some accept disturbed habitat, including the whole population of Dicrurus fuscipennis; (ii) Moheli: several equivalent birds adapt better to secondary vegetation than on Grande Comore; (iii) Anjouan: the most disturbed; some endemics survive, showing their capacity for adaptation; (iv) Mayotte: all forests are new and situated lower than on the other islands. While most prefer 'forest', some are odd: Nectarinia coquereli is more common outside forest and the local Foudia eminentissima is restricted to non-forest, as on Aldabra, while it is mostly a forest bird elsewhere. Habitat adaptation is an indication of survival possibilities: many endemics can seemingly survive if 'forest' (even planted) persists. A variable picture appears for the other species. Surprisingly, the perspectives for most introduced birds are not bright, except for Acridotheres tristis, nowadays the most common bird.
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