Classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Carcharhiniformes
Family: Carcharhinidae
Genus: Carcharhinus
Species: C. limbatus
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Carcharhiniformes
Family: Carcharhinidae
Genus: Carcharhinus
Species: C. limbatus
Common Name
Blacktip shark
Morphology
The blacktip shark has a robust, streamlined body with a long, pointed snout and relatively small eyes.
Development in the blacktip is viviparous, meaning they give birth to live, free-swimming young like others in the carcharhinid family. Males reach sexual maturity between 4.4 and 5.9 feet (135-180 cm). Females reach maturity at 3.9-6.3 feet (120-190 cm). Gestation last 10-12 months, and they give birth in late spring and early summer to 1-10 pups. Females give birth in inshore estuarine nursery grounds where the young remain for the first years of their lives.
Development in the blacktip is viviparous, meaning they give birth to live, free-swimming young like others in the carcharhinid family. Males reach sexual maturity between 4.4 and 5.9 feet (135-180 cm). Females reach maturity at 3.9-6.3 feet (120-190 cm). Gestation last 10-12 months, and they give birth in late spring and early summer to 1-10 pups. Females give birth in inshore estuarine nursery grounds where the young remain for the first years of their lives.
Biology
The blacktip shark is an extremely fast, energetic predator that is usually found in groups of varying size. There is segregation by sex and age; adult males and non-pregnant females are found apart from pregnant females, and both are separated from juveniles. In Terra Ceia Bay, Florida, a nursery area for this species, juvenile blacktips form aggregations during the day and disperse at night. They aggregate most strongly in the early summer when the sharks are youngest, suggesting that they are seeking refuge from predators (mostly larger sharks) in numbers. Predator avoidance may also be the reason why juvenile blacktips do not congregate in the areas of highest prey density in the bay. Adults have no known predators. Known parasites of the blacktip shark include the copepods Pandarus sinuatus and P. smithii, and the flatworms Dermophthiris penneri and Dionchus spp., which attach the shark's skin.This species is also parasitized by nematodes in the family Philometridae, which infest the ovaries.
Distribution Map
Importance: Ecological and Economical
environment =The blacktip reef shark is regularly caught by inshore fisheries in many parts of its range, It is caught for human consumption, fishmeal, and their fins enter the oriental sharkfin trade, for sharkfin soup. Their livers are also sought as a rich source of oil. In Indonesia, it forms part of the catch of sharks, rays and skates, which has increased dramatically from 1,000 tonnes in 1950 to 95,600 tonnes in 1997. It is also fished off India and Thailand and in the western Indian Ocean, where it is caught on longlines and in gill nets. In northern Australia it is occasionally caught and eaten by some Aboriginal communities. Due to such extensive exploitation, it is thought that blacktip reef shark populations are likely to be depleted.
It is possible that the blacktip reef shark may also be impacted by the destruction of coral reefs It is estimated that 20 percent of the world’s coral reefs have already been effectively destroyed and show no immediate prospects of recovery, and 24 percent of the world’s reefs are under imminent risk of collapse. This is the result of numerous human activities that cause an increase in sediment, nutrients and pollutants to enter the oceans and stress the fragile reef ecosystems
The blacktip shark is a targeted species in a number of commercial fisheries, including the longline fishery off the southeast coast of the U.S. where it comprises about 7% of the catch. It is also regularly captured in fixed bottom nets and in shrimp trawls. The meat is used for fish meal or sold in local markets for human consumption. The fins are sold to Asian markets. The hides have also been used for leather.
economic ($) Although usually considered harmless, C. amblyrhynchos may occasionally bite humans. The bites are serious, but rarely fatal. Accidents most often occur during spearfishing, when the sharks become aggressive in the presence of food. Careless divers who corner the animal in a reef canyon may also be attacked in self-defense. Additionally, there are areas of eastern Micronesia, particularly the Marshall Islands, where these sharks have a reputation for being aggressive toward humans.
Interesting Facts
When receptive to mating, a female blacktip reef shark swims slowly in a sinusoidal pattern near the bottom with her head pointed down; observations in the wild suggest female sharks release chemical signals that allow males to track them. Once the male finds her, he closes to around 15 cm (5.9 in) and follows her with his snout oriented towards her vent. A courting male may also bite the female behind her gills or on her pectoral fins; these mating wounds heal completely after 4–6 weeks. After a period of synchronous swimming, the male pushes the female on her side and positions her so her head is against the bottom and her tail is raised. Once the female is in position, the male inserts one of his claspers into her cloaca. Copulation lasts for several minutes, after which the sharks separate and resume their regular behaviors. Off Moorea, individual older females mate and give birth at a consistent time every year, often to within a week's precision, whereas younger females exhibit more variability in their timing. Younger females are also more likely to fail to become pregnant after mating. Young blacktip reef sharks commonly form large groups in water barely deep enough to cover their bodies, over sand flats or in mangrove swamps close to shore. During high tide, they also move onto flooded coral platforms or seaweed beds. Growth is initially rapid; one documented captive shark grew an average of 23 cm (9.1 in) per year in its first two years of life. The growth rate slows to around 5 cm (2.0 in) per year in juveniles and adults. Males and females mature sexually at lengths of 95 cm (37 in) and 97 cm (38 in) respectively off northern Australia, and 105 cm (41 in) and 110 cm (43 in), respectively, off Aldabra. Males mature at 97 cm (38 in) long off Palmyra Atoll
Vocabulary
DIATOMS= phylum hetorokophyta,class bacillariophy unicellular and eurokyotic
BLOOMS= A sudden increase in the abundance of an alga or phytoplanton
DINOFLAGELLATES= phylum diinoflagellate unicellular, eukaryoti, mostlyautotrophic
ZOOXANNTHELLAE=dinoflagellates that live within the tissue of reef corals and other marine animals
FORAMINIFERANS= (FORAMS) (PHYLUM GRANULORETICULOSA) PROTOZONS WITH A CALCAREOUS SHELL, OR TETS AND PSEUDOPODIA
BLOOMS= A sudden increase in the abundance of an alga or phytoplanton
DINOFLAGELLATES= phylum diinoflagellate unicellular, eukaryoti, mostlyautotrophic
ZOOXANNTHELLAE=dinoflagellates that live within the tissue of reef corals and other marine animals
FORAMINIFERANS= (FORAMS) (PHYLUM GRANULORETICULOSA) PROTOZONS WITH A CALCAREOUS SHELL, OR TETS AND PSEUDOPODIA
Resources
WIKIPEDIA
EXTRA:)
Blacktip Reef Shark The blacktip reef shark (Carcharhinus melanopterus) inhabits tropical and warm temperate seas. They are pelagic sharks meaning that they spend their entire lives swimming in the water column as opposed to resting on the bottom. They must always remain in motion in order to respire valuable dissolved oxygen from the water.
Size: The blacktip reef shark can reach up to six and a half feet in length.
Life Span: 12 to 25 years
Color: The body of this shark type is a bluish-gray color.
Range: Pacific and Indian Oceans
Habitat: The blacktip reef shark is very common in the coral reefs and shallow lagoons of the tropical Indian and Pacific Oceans. They are also beginning to enter the Mediterranean.
Food: The sharks most commonly feed on snakes and reef fish.
Reproduction: The blacktip reef shark has litters of two to four pups after a 16-month gestation period. They most commonly give birth in November and they give birth to live young.
Fun Facts: With a sleek body and speedy tail, the blacktip reef shark sneaks up on prey with ease. Cruising coastlines in large schools, blacktip reef sharks often jump out of the water during a feeding frenzy of schools of fish, rays and even small sharks.
Size: The blacktip reef shark can reach up to six and a half feet in length.
Life Span: 12 to 25 years
Color: The body of this shark type is a bluish-gray color.
Range: Pacific and Indian Oceans
Habitat: The blacktip reef shark is very common in the coral reefs and shallow lagoons of the tropical Indian and Pacific Oceans. They are also beginning to enter the Mediterranean.
Food: The sharks most commonly feed on snakes and reef fish.
Reproduction: The blacktip reef shark has litters of two to four pups after a 16-month gestation period. They most commonly give birth in November and they give birth to live young.
Fun Facts: With a sleek body and speedy tail, the blacktip reef shark sneaks up on prey with ease. Cruising coastlines in large schools, blacktip reef sharks often jump out of the water during a feeding frenzy of schools of fish, rays and even small sharks.