Tourists watch from a boat at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

A catshark swims at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

A tourist swims between catsharks (Scyliorhinidae) at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

Tourists watch from a boat at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

Tourists watch a giant oceanic manta ray at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

View of the reef "Barrier Reef", around San Pedro Island, in Belize, on Oct. 22, 2013. Located on the coast of Belize, the reef "Barrier Reef", is the second lagest coral reef in the world after the Great Barrier Reef of Australia, with an approximate lenght of 300km, is part of the Mesoamerican Barrier Reef System. Is a set of coral reefs, located about 300 meters from northern coast and approximately 40km from the south. This is the most important touristic destination in Belize and it is vital for the fishing industry. It is estimated that it was formed about 500 millions of years ago. Among the big diversity of species that it has, there are the Caribbean reef shark (Carcharhinus perezzi) and the Blacknose shark (Carcharhinus acronotus), as well as fish of different colors that blend into the reef and is provided with some species of soft coral. The reef forms a white line that its shining from Ambergris Caye in northern Belize to Ranguana Caye in the south. In 1996 the United Nations Education, Science and Culture Organization (UNESCO) declared it as World Heritage. (Xinhua/David de la Paz)

A tourist swims at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

Tourists watch from a boat at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

A catshark swims at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)

A tourist swims at the reef "Barrier Reef" around San Pedro Island in Belize, on Oct. 22, 2013. The Belize Barrier Reef off the coast of Belize is part of the Mesoamerican Barrier Reef System, the world's second longest after Australia's Great Barrier Reef. Among the big diversity of species it has, there are Caribbean reef sharks, blacknose sharks (Carcharhinus acronotus) as well as fish of different colors that blend into the reef.(Xinhua/David de la Paz)