The Blacktip Shark, scientifically known as Carcharhinus limbatus, is known by many names depending on the region that it is found in, including; Spot-Fin Ground Shark, Small Blacktip Shark, Requiem Shark, Gray Shark, Common Blacktip Shark, and Blacktip Whaler.
This species is near threatened due to overfishing and destruction of their coastal habitat.
Characteristics and Appearance
Weight & Length
Blacktip Shark pups grow quickly and can reach 6 feet. An adult Blacktip Shark can grow as long as 8 feet and range in weight from 66 to 220 pounds. Blacktip shark females are larger than males, with the average length being 5.5 feet and the largest female being measured at 6.8 feet.
Physical Characteristics & Color
Blacktip sharks are medium-sized sharks with a distinct, pointed nose. Their name comes from the characteristic black or dark gray coloring on the tips of their dorsal, caudal, and pectoral fins. These sharks have large, wide jaws with many teeth to help them eat bony fish and crustaceans.
They have a torpedo-shaped body that helps them to navigate through the water with little effort.
Blacktips might be described as some of the most “sharklike” sharks, with their characteristic wide eyes and long snouts. Despite their appearance, they are unusually docile animals, only becoming aggressive toward humans when hunting or eating.
Black tip sharks have blacktips on all of their fins (pectoral fin, dorsal fin, and tail fins), except for the anal fin. They are often mistaken for a Spinner Shark but can be differentiated by the white anal fin. The Spinner Shark has black tips on its anal fin.
Lifespan and Reproduction
Blacktip Sharks can live up to 10 years old. Males mature by the age of 4 or 5, and females reach maturity later, at age 6-7. Females can start reproducing at age 4 or 5 years and continue to have pups for life. The Blacktip Sharks swim in gender-specific schools, males swim together and females swimming amongst themselves until mating season.
The blacktip shark schools combine during mating season. The mating season is from March to June. Gestation takes 11 to 12 months. Blacktip sharks are viviparous, which means that the young develop inside them, which means the females have live births and do not lay eggs. The mother leaves the pups near shallow coastal waters to keep them away from other sharks and other predators.\
Where does the Blacktip Shark live?
The Blacktip Shark lives in coastal waters worldwide and can be found in large numbers along the Gulf of Mexico. They have been spotted as far north as Cape Cod in Massachusetts. In the Pacific, Blacktip Sharks are found from southern California to Peru. Blacktip Sharks can also be found in the waters of the Indian Ocean.
Blacktip Sharks live in the waters of South Africa and Madagascar. These sharks can also be found from the east coast of China, throughout India’s coast, the Persian Gulf, and the Red Sea. The blacktip shark is also found in the waters of the Pacific Islands, such as the Galapagos Islands, Hawaii, Tahiti, as well as other southern Pacific Islands to the north coast of Australia.
Due to their closeness to the coast, the Blacktip Shark is often the shark species that humans encounter in the water. Scientists believe most of the shark bites in Florida can be attributed to the Blacktip Shark. In Florida, Blacktip sharks account for 16% of shark attacks, resulting in minor wounds. While not an aggressive shark, the Blacktip Shark will protect its food.
Food and Diet
What does the Blacktip Shark eat?
Blacktip Sharks are carnivores. They feed on small schooling fishes, such as herring, sardines, menhaden, mullet, and anchovies. They eat other bony fish, including catfish, groupers, jacks, flatfishes, and porcupine fish. Blacktip Sharks also feed on cephalopods, stingrays, crustaceans, and shrimp.
The blacktip shark often follows fishing boats so that they can eat the discarded fish. Blacktip Sharks are known to feed at dawn and dusk.
Threats and Predators
Humans pose a threat to Blacktip Sharks due to accidental capture in fishing nets, commercial fisheries, and local fisherman overfishing due to the demand for the meat and the fins. The meat is considered tasty, and the fins are used for soup in East Asian markets.
The fins are also known to have medicinal purposes in East Asia. The fish can get trapped in fishing nets, and the young can get caught in bottom trawls.
Blackfin Sharks are often fished for sport as they are known to put up a fight, leaping in the air when caught. The International Game Fish Association (IGFA), has it on file that the record size Blacktip Shark was caught in the Bahamas using a rod and reel fishing pole and weighed 270 pounds.
Another way in which humans posed a threat to the Blacktip Shark is coastal development. Destruction of coral reefs and mangroves means fewer places to set up their nurseries and hide puppies from predators. These areas are also where sharks find their prey, so hunting for food is becoming more difficult.
With increasing acidity and ocean temperatures due to global warming, the Blacktip Sharks’ food availability has shifted. Migration patterns have changed because the sea creatures they eat struggle to survive in the warmer acidic waters close to the equator.
To access food for the survival of the species, the Blacktip Shark is finding new waters. They move away from the hot waters close to the equator and head towards the north and south poles, following their food supply, seeking cooler waters.
The increased acidity in the ocean waters is causing other problems aside from the movement of the Blacktip Sharks food. Researchers are finding that the acid is eroding sharks teeth and their scales. This will hamper sharks’ ability to hunt, feed, and swim. This is not an issue for the Blacktip Shark alone; all sharks are facing the same challenges when it comes to their teeth erosion and corrosion of their scales.
As an apex predator, the Blacktip Sharks don’t have a long list of predators; however, they do have some. Predators that Blacktip Sharks have to be wary of include fellow, larger sharks; this is particularly true for young Blacktip Sharks that are more vulnerable to predators than their adult counterparts. Large Groupers can also eat Blacktip Sharks.
As mentioned above, another predator is humans, as the Blacktip Shark is fished not only for its reputation as great tasting meat but for its fins, which are supposed to have medicinal benefits.
In some cases, the fins are put in capsule form, and traditional Chinese medicine claims these benefits include nourishing the blood, enhancing appetite, and energizing various internal organs. It is worth noting that these claims have not been confirmed by the U.S. Food and Drug Administration.
Parasites are another thing that Blacktip Sharks need to be wary of. External parasite copepods Pandarus sinuatus and Pandarus smithii are found on the bodies of the sharks. They attach to the skin of the sharks. Nematodes also parasitize blacktip Sharks in the family Philometridae, which infest the ovaries.
Blacktip Sharks are classified as Near Threatened due to overfishing and destruction of habitat. The United States and Australia are the only two countries managing fisheries catching Blacktip Sharks. At this time, there is no international management plan for Blacktip sharks.
Fun Facts About Blacktip Sharks
- Blacktip Sharks are sometimes spotted above water. They leap to the surface, spin several times and splash down on their backs. It is said this is how they catch their prey. This behavior is one of the reasons they are often confused with Spinner Sharks since they exhibit similar behavior and have other physical characteristic similarities.
- In 2008 DNA evidence confirmed that a female shark fertilized her egg, impregnating herself without help from a male. It is unsure how this happens, but it has occurred in other shark species as well.
- The oldest observed Blacktip Shark reached the age of 15.5 years old.
- Blacktip Sharks have a very keen sense of smell. Scientists have found that they can detect fish flesh diluted to one part per 10 billion parts of seawater.