The Blacktip Sharks Collection

About the Species

The oceanic blacktip shark (separate from the blacktip reef shark) is a coastal shark that occupies tropical and subtropical seas. They usually reside within the first 30 metres of the water column. They are commonly spotted in estuaries, mangroves, river mouths, and bays, as well as coral reef drop-offs and within continental shelves. They feed on a wide assortment of bony fish, keeping many populations in check, and playing a crucial role in marine ecosystem maintenance.

Biology

Physical Traits

• Blacktip sharks are normally two metres in length and are distinguished by their slender, streamlined bodies, pointy snouts, and smaller eyes.
• They acquired their name from their peculiar black colouration at the end of all of their fins (excluding their anal fin, which is white). The colouration of the rest of their body customarily transitions from a grey-brown colour on top of their body to white colour on their     lower belly.
• They accommodate 15 rows of teeth, backed by a constant supply of replacements.

Reproduction and Lifespan

• Oceanic blacktips are viviparous (bear live birth). Although they have longer gestation periods (11-12 months), they give birth to live young that are born fully nourished, developed, and ready to take on the world, with little to no time or resources spent by the mother     nurturing young after they are born.
• Birthing grounds are typically characterised by warmer, shallower waters to ensure safety.
• Males reach maturity earlier than females (4-5 years compared to 6-7 years), and females give birth every other year to litters ranging from one to ten pups.
• Blacktips have a relatively shorter lifespan, with a max of around 12 years.

Viability

Threats and Climate Change

• Blacktips are a common catch for recreational and commercial fishing, especially due to their highly marketable and desired meat and fins (for culinary delicacies such as shark fin soup and Australian ‘flake’). Their hide is also in high demand for leather production, and the fatty oils in their livers are often used for supplement production.
• Because they give birth on inshore, warm-temperate coasts, they are more exposed to human impacts such as habitat destruction, pollution, harassment, and fishing pressure.

Conservation Status

• According to the IUCN red list of species, blacktips are “Near Threatened”, meaning they are vulnerable to being threatened in the future.
• Blacktips are fished for sport and are sold in local markets. They receive fishery management in Australia and the USA because it is one of the most sought-after commercial shark species in both countries.
• International management of this individual shark species has yet to be achieved.

Current Research

• Recent research suggests that the South African population of blacktip sharks partake in multiple paternity. This is where a female can uptake and store sperm from multiple males, generating a single litter with multiple fathers.
• In an attempt to deter sharks from chasing fishing boats and accidentally getting caught in nets, magnets can be attached to the nets. The magnets are thought to discourage the sharks by provoking their electroreceptors.