plant kingdom originated here. Gatun Lake covers about , a vast tropical ecological zone and part of the Atlantic Forest Corridor. Ecotourism on the lake has become an industry for Panamanians. Gatun Lake also provides drinking water for Panama City and Colón. Fishing is one of the primary recreational pursuits on Gatun Lake. Non-native peacock bass were introduced by accident to Gatun Lake around 1967 by a local businessman, and have since flourished to become the dominant angling game fish in Gatun Lake. Locally called Sargento and believed to be the species Cichla pleiozona, these peacock bass originate from the Amazon, Rio Negro, and Orinoco river basins, where they are considered a premier game fish. Lock size The size of the locks determines the maximum size ship that can pass through. Because of the importance of the canal to international trade, many ships are built to the maximum size allowed. These are known as Panamax vessels. A Panamax cargo ship typically has a deadweight tonnage (DWT) of 65,000–80,000 tons, but its actual cargo is restricted to about 52,500 tons because of the draft restrictions within the canal. The longest ship ever to transit the canal was the San Juan Prospector (now Marcona Prospector), an ore-bulk-oil carrier that is long with a beam of . Initially the locks at Gatun were designed to be wide. In 1908, the United States Navy requested that an increased width of at least to allow the passage of US naval ships. Eventually a compromise was made and the locks were built wide. Each lock is long, with the walls ranging in thickness from at the base to at the top. The central wall between the parallel locks at Gatun is thick and over high. The steel lock gates measure an average of thick, wide, and high. Panama Canal pilots were initially unprepared to handle the significant flight deck overhang of aircraft carriers. knocked over all the adjacent concrete lamp posts while passing through the Gatun Locks for the first time in 1928. It is the size of the locks, specifically the Pedro Miguel Locks, along with the height of the Bridge of the Americas at Balboa, that determine the Panamax metric and limit the size of ships that may use the canal. The 2006 third set of locks project has created larger locks, allowing bigger ships to transit through deeper and wider channels. The allowed