Distribution data on Achatina fulica Bowdich were obtained from pest control agencies and from a survey of potential localities randomly distributed in all provinces of Ecuador. Among the total of 1,236 localities, 1,065 (86.2%) held populations of the species. The snail was found to spread much faster than predicted and was present in areas not previously suspected to be under the risk of invasion. The most endangered and infested areas were the coastal and Amazonian regions of the country. According to the pest control reports from government agencies, A. fulica most often affected plantations of cocoa (24.8% of localities), plantain (11.8%) and banana (11.2%), but was also known to forage on 56 other species of cultivated plants. The survey of likely habitats in random localities showed a high infestation rate; urban and ruderal sites turned out to be important but largely neglected dispersal hotspots for the species. Regular observations on two populations in the city of Puyo (Pastaza province, Amazonia) showed that the growth rate and population density were high: reaching adult size took on average four weeks.