The Black Rat is one of two species of rats found in British Columbia, both introduced and considered invasive. Despite its name, the Black Rat has several colour forms: it may be black to light grey-brown in colour with a lighter morph that ranges from slate grey to white (Nagorsen 2005). It has a slender body and large hairless ears and a noticeably long tail that is longer than the head and body combined. Its smaller size and the long tail separate it from the Norway Rat.
The Black Rat is found in Canada primarily in agricultural and urban areas (Nagorsen 2005. Its exact date of arrival in BC is unknown, although the earliest collections from the province were by Lord in 1858 (Nagorsen 2005). However, it is now reported from greater Vancouver, the lower Fraser Valley, the Queen Charlotte Islands, Vancouver Island and Cortes Island (but is absent from other islands adjacent to Vancouver Island). Although initially found primarily around dumps and waterfront areas, "on southern Vancouver Island and in North Vancouver it is found in forested habitats well away from human dwellings" (Nagorsen 2005). Nagorsen (2005) reports this species is less common than BC's other species of rat--the Norway Rat (Rattus norvegicus).
Historical Note:
In their 1958 publication Alien Animals of British Columbia, Carl and Guiguet summarize the species occurrence in BC at that time: "This species apparently arrived later than the Norway Rat (dates unknown), but it cannot compete with that species where it comes in contact. It is less common than the Norway Rat in most areas of the province, but it is well-established on the Queen Charlotte Islands and the mountains adjacent to Vancouver..."
