The flag of 18th-century pirate Calico Jack. Piracy is a robbery committed at sea, or sometimes on the shore, without a commission from a sovereign nation (robbery with sovereign commission is privateering, and distinct from piracy). Seaborne piracy against transport vessels remains a significant issue (with estimated worldwide losses of US $13 to $16 billion per year[1][2]), particularly in the waters between the Pacific and Indian Oceans, off the Somali coast, and also in the Strait of Malacca and Singapore, which are used by over 50,000 commercial ships a year. A recent[3] surge in piracy off the Somali coast spurred a multi-national effort led by the United States to patrol the waters near the Horn of Africa to combat piracy. While boats off the coasts of North Africa and the Mediterranean Sea are still assailed by pirates, the Royal Navy and the U.S. Coast Guard have nearly eradicated piracy in U.S. waters and in the Caribbean Sea.[citation needed] Maritime piracy, according to the United Nations Convention on the Law of the Sea (UNCLOS) of 1982, consists of any criminal acts of violence, detention, or depredation committed for private ends by the crew or the passengers of a private ship or aircraft that is directed on the high seas against another ship, aircraft, or against persons or property on board a ship or aircraft. Piracy can also be committed against a ship, aircraft, persons, or property in a place outside the jurisdiction of any state. The Jolly Roger is the traditional name for the flags of European and American pirates and a symbol for piracy that has been adopted by film-makers and toy manufacturers.