Habitat use and abundance of a low-altitude chameleon assemblage in eastern Madagascar

We studied the density and abundance of chameleons in a lowland Malagasy rainforest during the austral summer and winter. Nocturnal searches for chameleons were conducted along transects within relatively intact forest and vegetation on abandoned agricultural land adjacent to the forest. Four chameleon species were encountered during the study, Brookesia superciliaris, Calumma parsonii parsonii, Calumma nasutum and Furcifer pardalis. Brookesia superciliaris was most common inside relatively intact forest and the few individuals located in the regenerating forest on abandoned agricultural land were found in tiny, isolated patches of degraded rainforest next to rivers. Calumma p. parsonii was only encountered on three occasions in relatively intact forest and was a rare member of the community. The abundance of C. nasutum was highest in relatively intact forest but this species also occurred in vegetation on abandoned agricultural land. Furcifer pardalis was only found on the abandoned agricultural land, where it was observed laying eggs in sandy soil in August. The abundance of all species in habitats alongside rivers was higher in January than July–August, with the exception of C. p. parsonii, which was not detected during the former period. Additional investigations into habitat preference of chameleons and surveys in other forests in region are needed to establish whether the low abundance of C. p. parsonii and the absence of the Brookesia minima group at this site are related to 1) abiotic factors associated with altitude, 2) physical barriers that have prevented dispersal, or 3) the selective logging that occurred at the site until 1993.