Squalo Nutrice Ginglymostoma cirratum
The Nurse Shark (Ginglymostoma cirratum) is an elasmobranch fish within the family Ginglymostomatidae.
They are directly targeted in some fisheries and considered as bycatch in others. The conservation status of the nurse shark is globally assessed as being data deficient in the IUCN List of Threatened Species owing to the lack of information across its range in the eastern Pacific Ocean and eastern Atlantic Ocean.
They are considered to be a species of least concern in the United States and in the Bahamas, but considered to be near threatened in the western Atlantic Ocean, because of their vulnerable status, in South America and reported threats throughout many areas of Central America and the Caribbean.
Nurse sharks are opportunistic predators that feed primarily on small fish and some invertebrates. They are typically solitary nocturnal animals, rifling through bottom sediments in search of food at night, but often gregarious during the day forming large sedentary groups. Squalo Nutrice Ginglymostoma cirratum
(Extract from Wikipedia)
Coral reefs deliver ecosystem services for tourism, fisheries and shoreline protection. Coral reefs are fragile, partly because they are sensitive to water conditions. They are under threat from excess nutrients (nitrogen and phosphorus), rising temperatures, oceanic acidification, overfishing (e.g., from blast, fishing, cyanide fishing, spearfishing on), sunscreen use, and harmful land-use practices, including runoff and seeps (e.g., from injection wells and cesspools).
Over 4,000 species of fish inhabit coral reefs. The reasons for this diversity remain unclear. Hypotheses include the “lottery”, in which the first (lucky winner) recruit to a territory is typically able to defend it against latecomers, “competition”, in which adults compete for territory, and less-competitive species must be able to survive in poorer habitat, and “predation”, in which population size is a function of postsettlement piscivore mortality. Healthy reefs can produce up to 35 tons of fish per square kilometer each year, but damaged reefs produce much less.
(extract from Wikipedia)