Towards the end of the nineteenth century, British colonists in Jamaica became increasingly exasperated by the damage caused to their sugar plantations by rats. In 1872, a British planter attempted to solve this problem by introducing the small Indian mongoose (Urva auropunctata). The animals, however, turned on Jamaica's insectivorous birds and reptiles, leading to an explosion in the tick population. This paper situates the mongoose catastrophe as a closing chapter in the history of the nineteenth-century acclimatization movement. While foreign observers (...) saw the introduction of the mongoose as a cautionary tale, caricaturing British Jamaica as overrun by a plague of weasels and ticks, British colonists, administrators and naturalists – identifying a gradual decline of both populations – argued that the ‘balance of nature’ would eventually reassert itself. As this paper argues, through this dubious claim they were attempting to retrospectively rationalize or justify the introductions and their disastrous aftermath. This strategy enabled them to gloss over the lasting ecological damage caused by the mongoose, and allowed its adherents to continue their uncritical support of both the Jamaican plantation economy and animal introductions in the British Empire. (shrink)