Fragmented distribution and genetic differentiation of the Forest Fody, Foudio eminentissima algondae, on the island of Mayotte (Comoros)

Most of the species in the genus Foudia (Passeriformes, Ploceidae), endemic to the Malagasy region, are endangered and one is already extinct. We stud ied the distribution of the Forest Fody, Foudia eminentissima, algondae, on Mayotte (Comoros) during two surveys (October 1993, February 1995), and re viewed all other available data. The field surveys showed that 1) the distr ibution of the Forest Fody population on Mayotte is very patchy; 2) the sir e of the Mayotte population is larger than anticipated, probably several th ousands of individuals, distributed in six different subgroups; 3) there is no evidence fore decrease in population size nor in population range over the last decade, perhaps even to the contrary; 4) the species occupies a wi de range of open habitats, mainly along the coast (we never observed it in forested areas). Although sample sizes were small, bandsharing analyses on multilocus DNA-fingerprints of 44 blood samples (four different subgroups) suggested a rather high degree of isolation between subgroups, even though maximum distances did not exceed 30 km. The rather strong isolation effects over short distances, together with differences in habitat occupation betw een the subgroups, may be important topics for further study and for future conservation measures.