 Before the early 1840s , the cane toad had been introduced into Martinique and Barbados , from French Guiana and Guyana . An introduction to Jamaica was made in 1844 in an attempt to reduce the rat population . Despite its failure to control the rodents , the cane toad was introduced to Puerto Rico in the early 20th century in the hope that it would counter a beetle infestation ravaging the sugarcane plantations . The Puerto Rican scheme was successful and halted the economic damage caused by the beetles , prompting scientists in the 1930s to promote it as an ideal solution to agricultural pests . 
