Lough Carra is a marl lake of 16 km2, in County Mayo, Ireland, about 13 km south of Castlebar. It is approximately 9.7 km long and varies in width from 370 m to 1.6 km. The average depth is 1.8 m, with a maximum of 18m. It drains into Lough Mask via the Keel River.
It is a well-known brown trout lough, and is situated northeast of Lough Mask.
Seven species of fish have been recorded in Lough Carra and its feeder streams. Brown trout, Eel, Three-spined stickleback and Brook lamprey are all indigenous. Unil recently (2013), Pike was considered to have been introduced, but research has suggested that the Pike is also a native species having been in the Lough for around 8,000 years. Perch and Roach are relatively recent introductions, the latter having arrived since the year 2000.
