Caribbean Reef Shark

You likely grew up with a fear of sharks. Many people fear the unknown, and when all the information in the media Is about shark attacks, many people internalize a lot of that. Shark attacks are very rare and not every shark is as aggressive as the ones were reported in the attacks.

There are over 400 species of sharks and all of them have unique characteristics that make them special. The Caribbean reef shark is one of those sharks. This is a large shark that has an impressive presence. The Caribbean reef shark is very unique and there are a lot of things that make it similar to other sharks but also many traits that set it apart from others.

Sharks

Sharks are the ocean’s top predators. They’ve evolved into over 400 different species and they have varying diets and behavior. There are a lot about sharks that are unknown to many people. Understanding sharks in general is very important to understanding the individual species of sharks.

Sharks fall into a subclass of fish called elasmobranchii. Sharks in the subclass have skeletons made from cartilage and they have five to seven gill slits on the sides of their heads. This is different from many fish, who have skeletons made from bone and 1 gill on each side of their head. Sharks use the gills on the side of their head to filter oxygen from the water to breathe. They have multiple rows of teeth that fall out and grow back routinely. Even though they all have rows of teeth, some are serrated like a razor and others have triangular teeth.

Sharks can be found in both deep and shallow waters. They all migrated vast distances to feed and breed. There are some differences between them. Some shark species are solitary while others hang out in groups. Some sharks are known to congregate in large groups to socialize. Scientists still are confused about a lot of the behaviors of sharks. They’re still trying to pinpoint how long sharks live and they’ve only studied a fraction of shark species. Notably, the Greenland shark is the earth’s longest living vertebrate and it has lived to be 272 years old.

Although sharks are known for their human attacks, humans are not their preferred food. Shark attacks have increased steadily since the 1900s but this might be the result of better recording and a rising human population. Shark attacks are still very rare and a beachgoer has a 1 in 11.5 million chance of being bitten. This means they’re more likely to be struck by lightning or die from drowning than from a shark attack. Even though shark attacks are seen in horror movies sharks bite people out of curiosity, defense, or confusion.

Sharks are not a significant threat to humans but humans are a threat to them. Humans are responsible for the drastic decrease in shark populations. This decrease occurs due to overfishing. 100 million sharks are killed each year and they’re mostly to supply expensive dishes. Fisheries that catch whole sharks often cut off the fins and dump them back into the ocean where they bleed out or drown. This is done to save space on the boat and avoid surpassing fishbone braids but it’s very deadly to the shark population. Many fisheries have outright banned shark fishing.

Another thing that often impacts sharks are rising water temperatures in coastal developments. They contribute to the shrinking shark populations because the coastal developments are destroying mangroves in coral reefs. These are places that are used for breeding, hunting and protecting young shark pups. A drop in numbers is bad for sharks, but it could also be bad for ocean health in general. Because they’re top predators of the ocean, they are critical for balancing the food web.

Name of Shark Article is About

What is a Requiem Shark

The Caribbean reef shark is a Requiem shark. These are one of the largest and best-known families of sharks. This family of sharks are all strong swimmers that live alone or in small to large groups. Most of the species in this family are torpedo shaped and slender. They mostly have rounded snout and gray or brown coloring. They all have light-colored undersides. They all look very similar to each other and individual species are difficult to recognize. This species is commonly seen in the Gulf of California and the Revillagigedo islands.

Requiem sharks have a lot of similar traits. They’re largely Circle tropical although some of them live in temperate Waters. They’re mostly pelagic but they may be Oceanic or Coastal sharks also. They have sophisticated sensors of vibration in electrical conductivity. Most of them are voracious predators that feed on other fishes. This family of sharks usually don’t attack humans but about half of all reported attacks are from Requiem Sharks. Here’s more information about the Caribbean reef shark.

Description

The Caribbean reef shark is a heavy-bodied shark with the streamlined shape that’s very recognizable and many other sharks. As a matter of fact, the Caribbean reef shark is very difficult to distinguish from the other large Requiem shark species. And usually reaches around 2 to 2.5 meters or 6.6 to 8.2 feet long. The largest recorded length of the shark is 3 meters or 9.8 feet. The maximum reported weight of this shark is 70 kilograms or 150 pounds. The shark usually has a dark gray or grey brown coloration on the top of their body and a white or white yellow underside. Their flanks have a white band on it that make it recognizable. The fins are not prominently marked and the undersides of the paired fins, the anal fin and the lower lobe of the caudal fin are a dusky color.

It’s snout is short and broad with a rounded end. It doesn’t have the prominent flaps of skin beside the nostrils like other sharks do. Its eyes are large and circular with membranes which are protective third eyelids. They have 11 to 13 rows of teeth in either half of both of their jaws. Their teeth have broad bases and serrated edges which make them formidable predators. The front two to four teeth on each side are erect and the others are oblique. When the Caribbean reef shark opens his mouth it can be very scary.

It has a lot of useful features like fins and gills that help it swim and breathe. The five pairs of gill slits are moderately long with a third gill that lays over its pectoral fins. The dorsal fin is high and sickle shaped which makes it unique. There is a lower dorsal ridge behind the first dorsal fin before the second dorsal fin. The pectoral fins are long and narrow that taper to a sharp point. The dermal denticles, which are its protective scales that provide effective camouflage, are closely spaced and overlapping. All of these features come together to make the Caribbean reef shark one of the most formidable Requiem sharks.

Biology and Ecology

Even though it’s found in abundance in many areas the Caribbean reef shark is one of the least studied Requiem sharks. They are believed to play a major role in shaping Caribbean Reef communities. The Caribbean reef shark is more active at night with no evidence of seasonal changes in activity or migration throughout the year. The younger Caribbean reef sharks stay in a localized area throughout the year while adults will range over a wider area. There’s sometimes seen resting motionless on the seafloor inside caves. This was the first active shark species where this Behavior was reported. They were originally called the sleeping sharks by Eugenie Clark in 1975 and they were found inside the caves at Isla Mujeres off the Yucatan Peninsula.

It was later determined that the Caribbean reef shark was not actually sleeping as their eyes would follow the divers as they approached. Clark speculated that these freshwater upwellings inside the caves might loosen parasites on the shark and produce an enjoyable effect. If threatened the Caribbean reef sharks will usually perform a threat display, which is usually triggered by biological conflict between competing organisms. Only 23 shark species are capable of producing these displays when threatened by competitors. When the Caribbean reef shark performs a threat display, they swim in short jerky fashions with frequent changes in Direction. They also have repeated brief drops of their pectoral fins.

Juvenile Caribbean reef sharks are often preyed upon by larger sharks like the tiger shark. There are a few parasites that are known for its presence on the Caribbean reef shark and one is the dark variegated Leach which is often seen sailing from the shark’s dorsal fin. In Northern Brazil, younger Caribbean reef sharks seek out cleaning stations occupied by yellow nose gobies that clean the sharks of parasites while they lie still at the bottom of the shark.

Habitat

Caribbean reef sharks are found throughout the tropical Western Atlantic Ocean from North Carolina in the north to Brazil in the South including Bermuda. They’re also found in the northern Gulf of Mexico and the Caribbean Sea. It is extremely rarely found north of the Florida Keys. It prefers shallow waters on or around coral reefs and it’s commonly found near the drop-offs at the reef’s outer edges. This shark is most common in water shallower than 30 m but it has been known to dive deep into the water at 378 meters.

Diet

The Caribbean reef shark feeds on a variety of reef dwelling bony fishes and cephalopods. They will also feed on some Elasmobranchs such as Eagle Rays and yellow stingrays. It’s attracted to low frequency sounds because these sounds are indicative of struggling fish. In one observation of a 2 meter long male Caribbean reef shark, it was hunting a yellow Snapper and the shark languidly circled and made several half-hearted turns towards its prey. It began accelerating and swung his head sideways to capture the Snapper at the corner of its jaws. Younger sharks feed on small fishes, shrimps and crabs. These sharks are capable of averting their stomachs to cleanse indigestible particles, parasites and mucus from its stomach lining.

This shark is on the Near Threatened list of the International Union for Conservation of Nature. Their coral reef habitats are being destroyed and they’re overfished in many areas. Learning about the Caribbean Reef Shark is the first step for understanding how you can make a change in the world around.