Sven Mecke and colleagues call for prior assessment of ecological risks that might be associated with eradication measures against the invasive Asian common toad Duttaphrynus melanostictus (Nature 511, 534; 2014). The Amphibian Specialist Group in Madagascar — part of the International Union for Conservation of Nature's Species Survival Commission network — is already undertaking such an evaluation, along with local and international experts.

We disagree that the effects of an invasive species need to be fully understood before starting control operations. Experience with other invaders shows that this could take decades, and swift action is crucial to stop an invasion from becoming widespread. We already know that D. melanostictus is invasive elsewhere in the tropics and is a biosecurity hazard in Australia.

Nationally coordinated by Christian Randrianantoandro, our efforts include determining the toads' distribution, providing educational materials to local communities and assembling experts to develop the feasibility study. We shall use genetic analyses to identify the source of introduction and will screen toads for pathogens and parasites. All toad sightings in Madagascar have so far been in urban and nearby degraded habitats, which would limit any threat to native biota should an eradication programme be carried out.

Costs of the preliminary assessment are estimated at US$50,000. The Amphibian Survival Alliance is running an online fund-raising campaign, and we hope to involve international non-governmental organizations. A globally coordinated response may still stop the toads from invading Madagascar.