The Blue Shark, also known as the Great Blue Shark, is indeed a shark of the family Carcharhinidae species distinguished by its all-white underside and striking deep-blue pigmentation.
Their sleek bodies with their large, round eyes and elongated snouts, make them one of the ocean’s most distinctive inhabitants. These creatures are renowned for their epic migrations, navigating thousands of miles across the world’s temperate and tropical seas. Although they may appear intimidating, blue sharks are typically non-aggressive towards humans, favoring a diet of smaller fish and squid.
Embark on a journey with us as we uncover the captivating characteristics, behaviors, and conservation challenges of these magnificent deep-sea wanderers.
Appearance
The majority of adult Blue Sharks are between 5.6 and 7.2 ft in overall length, while particular specimens can reach measurements of 13 ft and a weight of around 454 lbs. The Blue Shark is renowned for its eye-catching contra coloring, or dark blue back contrasted with a pure light belly.
The shark’s top blends into the ocean floor, and its bottom imitates the sunlight as seen from above the water, acting as a kind of camouflage. A large binocular field of view is supported by the substantial spacing between the shark’s eyes. They are further distinguished by having long, slender pectoral fins.
It has a saw-like row of teeth on the top, and bottom jaw, alongside a sharp nose.
Habitat
Blue sharks are a pelagic species that live in the open ocean, and are one of the most widely distributed of all shark species throughout breeding seasons to undergo internal fertilization and procreate.
They inhabit both tropical and temperate waters worldwide, preferring cooler temperatures between 7 to 16 degrees Celsius. They are highly migratory and can be found from the surface down to depths of about 350 meters.
Blue sharks can be found as far south as Chile and as far north as Norway.
They prefer water temperatures between 54-68 °F, but have been found in waters with temperatures ranging from 45-77 °F. Except for Antarctica, these pelagic sharks are found off of the coastline of every nation.
Diet
Blue sharks have a diverse diet that consists of small fish, invertebrates, cephalopods (like shrimps and squid) and small sharks. However, they are opportunistic feeders and will also consume larger prey such as octopuses and smaller sharks.
Occasionally, they have been known to eat seabirds and even garbage discarded by ships. Their long, slim bodies allow them to be swift and agile in the water, making them efficient hunters.
Reproduction
Blue sharks are viviparous, nourishing their young in the uterus via a placenta before giving birth to live pups. In rare instances, litters as large as 135 pups have been recorded, but it is thought that 25–35 pups is more typical.
They mature earlier than some other species, at 4-6 years of age. Gestation lasts 9–12 months, and pups are born at 0.35–0.5 m.
They also sometimes come together in gender-specific schools as juveniles while not feeding, though their reason for doing this is not yet known. Males initiate mating by biting a female between her two dorsal fins, which is why females have significantly thicker skin in this area than males do.
Threats
Blue Sharks have a whole host of predators, including other members of the same species consuming them when they are still young in a cannibalistic fashion. The smallest members of the species get hunted by Great White or Tiger Sharks. Large species of seals, such as the Elephant Seal, can hunt and feed them, as has been documented.
They are listed as ”Near Threatened,” by the IUCN and make up 60% of all reported shark catches. Despite being considered one of the most abundant and resilient shark species, their populations are thought to be decreasing, with their decline intrinsically linked to the lucrative shark fin and growing shark meat trade.
The Blue Shark is frequently unintentionally entrapped in gillnet and longline operations that are meant to catch other fish because of its wider availability and large population density.
5 Interesting Facts About Blue Shark
- The longest recorded length of a blue shark is 12.6 feet, but some unverified reports suggest they can grow up to 20 feet.
- Blue sharks have an exceptional sense of smell and can detect a single drop of blood in an Olympic-sized pool.
- They are known for their long-distance migrations, with some individuals traveling over 5,700 miles in a single trip.
- Blue sharks play a crucial role in maintaining the health of marine ecosystems by controlling the populations of their prey.
- They have specialized cells in their eyes for night vision, making them effective hunters in low-light conditions.
FAQs
Are Blue Sharks dangerous to humans?
Seldom do Blue Sharks bite people. Although Blue Sharks typically don’t really attack humans, they will do it if they feel intimidated. Only 13 cases of bite involving the Blue Shark from 1580 to 2013 resulted in fatalities, with only 4 of those cases. People can go diving with Blue Sharks with the help of guides and emerge unscathed.
Are Blue Sharks aggressive species?
Blue Sharks are quite curious creatures, and if you are faced with one while diving, chances are that they find you a strange fish and most likely won’t attack you. However, if someone is spearfishing nearby, they can sense the odors in the water and stimulate them into more aggressive behavior.
What color is best to avoid Blue Sharks?
Divers and swimmers may significantly lower their risk of coming into contact with a Blue Shark by refraining from wearing swimsuits or dive equipment that is extremely bright or distinctive. During swimming, it is strongly suggested to use deep blue or dark fins, masks, tanks, and wetsuits.
Are Blue Sharks going extinct?
Generally, the Blue Shark is considered to be Near Threatened. This resulted from human-made activities, including large-scale fishing, which causes the sharks to become entangled or wounded, as well as active hunting for their fins and disposing of the remainder of the shark. This has had major effects on their declining numbers.
