Date:Fri 6/21/2024 5:03 PM
Happy Friday, everyone! Today's fish is the dusky shark!
The dusky shark, known by scientific name Carcharhinus obscurus, is a pelagic shark found worldwide along the continental shelf. They can be found on almost all shores, from Southern parts of North America, Eastern Shores of North America, stretching downard to Argentina, with a large population in the Gulf of Mexico. They can be found along the western shore of Africa, and some areas of the Eastern shore, and all around the shore of Australia, preferring tropical and subtropical regions. This shark is migratory, and when it starts getting warmer in the summer, these sharks move closer to the poles, however when it becomes colder again, they flee closer to the equador. Its range tends to overlap with that of the oceanic whitetip sharks, sandbar sharks, and silky sharks, making some sightings possibly discreditable, but it is identifiable by the sickle shaped dorsal and pectoral fins.
As an apex predator, dusky sharks are not relatively abundant. They have few significant predators, with most being larger sharks, which prey on juveniles.However, in beaches where shark nets have been set up, keeping larger sharks away, dusky sharks have moved in, decimating fish populations in the area unchecked. The diet of the dusky shark is wide, considering they will hunt all levels of the water column within the pelagic zone, preferring to hunt along the seafloor. The dusky shark has a bite force of 130 pound, and will eat just about anything. Any fish they can catch, crabs, barnacles, other sharks, turtles, marine mammals. This diet can support dusky sharks getting pretty large for a requiem shark. The largest recorded was 14ft in length, although most only get as large as 10ft.
Like other requiem sharks, the dusky shark has embryos that are nursed by a yolk well in the womb, and gestated for between 22-24 months. Litters of these sharks can have a range of 3-16 at a time, and breeding season is dependent on population and season. Newborns are only 2-3 feet in length, and those with smaller litters are larger. Then for the first year of the pups life, it will stay near the mother, before splitting off on their own. After this the juveniles will reach sexual maturity at about 5 years of age, with a lifespan of 40-50 years!
Have a wonderful Friday, everyone!