Distribution and Population Density of the Black-Eared Malagasy Poison Frog, mantella Milotympanum Staniszewski, 1996 (Amphibia: Mantellidae)

Abstract

We provide first data on the natural history of a poorly known species of frog from Madagascar, the black-eared Malagasy poison frog, Mantella milotympanum. Although this species has been intensively collected for the pet trade, not even one precise locality was published until 2003. We here provide further distribution records north and south of the known locality Fierenana, but the encountered populations showed variable colour and patterns intermediate between M. milotympanum and M. crocea, thus supporting the hypothesis that these are conspecific colour morphs, and that M. milotympanum might be a junior synonym of M. crocea. Intensive fieldwork at one site next to Fierenana, in February 2003, yielded some data on population structure and density. Snout-vent lengths ranged from 16–24 mm, weights from 0.4–1.4 g in adults, with only few subadults and no juveniles found. The population density, estimated by mark-recapture, was about 470 individuals per ha, which is a quite high density, taking into consideration that this population had probably been under commercial exploitation in the past. We propose that some of the forests in the Fierenana area should be included in the planned extension of Madagascar’s network of protected areas, but a controlled and sustainable exploitation should be allowed in these reserves in order to gain the support of local communities.