The Commonwealth of Puerto Rico is a Caribbean archipelago known for its vibrant culture, majestic mountains, and pristine beaches. But it is also known as a hotspot for sharks and seeing the night shark in the area for the first time is not much of a surprise for scientists.
These sharks have a large range in the Western Atlantic Ocean, from Delaware to southern Brazil and Argentina, and also in the Eastern Atlantic off Africa. It is even found in Cuba and its English name is the translation of "tiburón de la noche," which is given by Cuban fishermen who caught it only at night.
New Hub for Shark Research
The night shark (Carcharhinus signatus) was caught by a small-scale commercial fisher. It looks like any other shark in the Carcharhinidae family, known as requiem sharks, with its thin, silver-copper body, pointed head, huge eyes, and short fins, according to Forbes.
The news outlet further reported that these creatures are medium-to-large, energetic predators that are migratory and may be found in oceans all over the world. Since so many in this family look identical, it's understandable that the fisher was unaware that the shark they'd captured was the first night shark documented in Puerto Rico.
With the many shark discoveries in the past few years, Puerto Rico is slowly becoming a must-see shark research area. As Forbes reported, about 14 species of carcharhinid sharks have been reported in the Caribbean archipelago, although there could be more that were only undocumented because of the lack of monitoring and data reporting on the island.
Night sharks are a coastal and semi-oceanic species that may dive to depths of 820 feet (250 meters) or deeper during the day and often climb in the water column at night to around 98-164 ft (30-50 m) deep when they feed mostly on small fish and squid.
Only one adult female night shark was retrieved at a depth of 1,082 feet (330 m), despite the fact that they travel in groups. She became hooked in hook and line gear used in the deep-water snapper and grouper fisheries, making it Puerto Rico's first verified sighting.
More About Night Sharks
As per Flordia Museum, the night shark is a slender, medium-sized gray-blue shark that is frequently confused with other species. It has a long, pointed nose and a short dorsal fin, but otherwise has the usual requiem shark form and colors. It has huge eyes that allow it to survive at depths during the day and eat at the surface at night to aid it in its diel vertical migration.
in the past, it was caught only as a bycatch on billfish and tuna fishing expeditions. But the night shark is now being professionally targeted off Brazil's northeast coast for its fins and flesh.
On the other hand, the International Shark Attack File has shown no known night shark attacks on humans. Perhaps because of its deepwater habitat and nighttime activities, the night shark poses less of a threat to people.
The International Union for Conservation of Nature (IUCN), a global alliance of nations, governmental agencies, and non-governmental organizations, analyzed the species' conservation status and classified it as vulnerable.
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