evaluation de la qualite d`habitat appropriee pour les poulpes (octopus cyanea) d` andavadoaka dans la region sud ouest de madagascar

Abstract

The socio-economic importance of octopus fishing in Andavadoaka encouraged the fishermen
to establish temporary reserves for the sustainable management of this resource. This study
carried out in Andavadoaka in 2010 tried to figure out the environmental aspects of reef
habitats that affect the importance of Octopus cyanea and to understand the role of habitat
quality in the success of the temporary closure. Indeed, the coral cover, the holes abundance
and the rugosity were surveyed in 18 fishing sites including 9 reserves and 9 non-reserve
sites. The results show that the coral cover and the holes number are significantly important in
the reserves sites (m=13,1 ± 3,2 per 500 m2) whereas in non-reserve sites, the seagrass and
sand are highly predominant and the holes density is only 4.6 ± 1,9 per 500 m2. However, the
rugosity indexes between the reserved and non-reserved sites are homogeneous. A positive
correlation was observed between the coral cover and the catch. This means that the octopuses
are more abun