A killer whale thrashes around and circles its tank after outliving all of its offspring and friends in harrowing footage.
Dubbed the 'world's loneliest orca', Kiska is shown circling the perimeter of her tank and splashing water over the edge at MarineLand Park in Niagra Falls, Ontario, Canada.
Kiska, around 45-years-old, is believed to have been captured in the waters off Iceland in 1979.
