The spiral tusk of this cetacean that inhabits the waters of the Arctic Ocean may reach a length of 10 feet
Male narwhals can reach a length of 5 meters (16 feet) and weigh up to 1,800 kg 
(4000 lbs)... [DOC] [TLE] Narwhal: Unicorns of the Sea | Strange Animals [PAR] Dec 28, 2010 ... Order: Cetacea ... Narwhals can reach depths of 1,500 m (~4921 ft).