Madagascar is under toad attack. The Asian or Black-spined toad Duttaphrynus melanostictus (once known as Bufo melanostictus), has been found in the Toamasina area, one of the major ports of entry to the island

It is a true toad and a relative of the Cane toad (Rhinella marina), the most successful invasive amphibian species worldwide, best known for causing severe ecological problems in various islands throughout Oceania and the Caribbean as well as northern Australia, where massive efforts have been devoted to its eradication. Unfortunately, by the time they were implemented it was already too late as the species had already expanded its range too far for effective control.

There is a concern that the Asian toad may wreak similar havoc in Madagascar, where the native species may be threatened by predation, competition for resources, or suffer from effects of the toad’s natural defensive toxins should naïve predators consume them.


Much like the cane toad, Duttaphrynus melanostictus is highly fecund, producing up to 40,000 eggs per clutch. It is also poisonous, has a generalist diet and is well adapted for life in agricultural and urban area. At present, Duttaphrynus melanostictus appears to rapidly be expanding its distribution. We do not know yet when it arrived in Madagascar, but we suspect the first individuals may have possibly arrived with imported materials inside shipping containers. Considering the high fecundity of the toad and highly suitable habitat and climate there is a real concern that the species could rapidly spread throughout the island. Especially problematic is the likelihood of native predators (carnivore mammals, birds, snakes) attempting to feed on the toad, having evolved in the absence of similar taxa and their toxicity. Moreover, we really wonder whether the species could enter the residual rainforests of Madagascar, areas of exceptionally unique biodiversity and endemism. Not far from Toamasina there is the Betampona Integral Reserve, one of the last remaining of the once continuos low altitude rainforest belt, which harbors an exceptionally high number of endemic species, many of which have yet to be described (about one third of the species found there appear to be novel and in need of description).


Together with Malagasy authorities and under the coordination of the IUCN SSC Amphibian Specialist Group, delimitation surveys are in progress under the supervision of Madagascar Fauna and Flora Group working together numerous partners. These baseline data are necessary to prepare a suitable feasibility study for an eradication plan that will be integrated within the ACSAM (A Conservation Strategy for the Amphibian of Madagascar program. It is of paramount importance to raise funds to finalize the assessment of the alien species delimitation, to realize a feasibility plan and to implement a coordinated effort for the eradication of this toad with the help of professionals.

All online donations received in support of this project through the ASA will be directed towards better understanding of the distribution of Duttaphrynus melanostictus within Madagascar, the production and disseminationof education materials and the development of an management feasibility plan.


By Franco Andreone, Angelica Crottini, Devin Edmonds, Candace M. Hansen, James Lewis, Christian Randrianantoandro