Indispensable, the bulldog shark has been in the spotlight for several years! How not to talk about it when it makes the front page of the news two to three times a year! Indeed, it is on French territory, in Reunion Island, that this shark is made known to the general public because of the accidents and the impact that this can have on tourism. Yet it is a source of savings in other regions of the world!
Is it possible to remain objective with this animal? Avoid amalgamations so as not to disturb some of the “anti-shark” Internet users? Once again, this article, like the previous ones, will primarily deal with the species sheet of the animal. We will consider his behavior towards humans while underwater diving in the next issue of Le Mag.
Description:
The Bulldog shark gets its name from its appearance. It has a stocky, massive and heavy body, with an extremely short rounded muzzle and very small eyes. This shark is gray or olive brown with the tips of the fins a little darker than the rest of the body. The belly is whitish. The tips of the fins are darker in the juveniles. The dorsal fin is large and broad, sickle-shaped. Implanted very indented, the second dorsal is of reduced size. Well developed, the pectoral fins are broad and falciform. The pelvic fins are triangular and the falciform anal wing also. The upper lobe of the caudal fin is much more developed than the lower lobe, as in all carcharhiniformes. Its upper jaw is equipped with wide, notched triangular teeth and the lower jaw with pointed vertical teeth. It is often confused with bull shark (Carcharias taurus) because the English vernacular name for the bulldog shark is bull shark, which literally translates to bull shark and therefore is confusing. In order not to be mistaken - because there is no distinctive point on its fins - the eye is located vertically above its lower jaw.
Habitat:
The Bulldog Shark is found on the coasts of all tropical and subtropical seas around the world, but it is also semi-pelagic. It frequents waters between 0 and 150 meters deep, but prefers those less than 30 meters. It particularly likes muddy waters and more generally with high turbidity, for example the mouths of rivers after a tropical cyclone. It has the unique characteristic in sharks of acclimating in hypo-saline and hyper-saline waters, which allows it to go up rivers such as the Zambezi, the Tigris, the Mississippi, the Ganges or the Amazon. Therefore, bulldog sharks are often found in rivers even if they are far from the mouth and the sea. It has been observed in theAmazon in Peru, more than 3 km from the coast. The bulldog shark is also present in Lake Nicaragua where it has long been considered an endemic species under the scientific name of Carcharhinus nicaraguensis. It is common in theAtlantic and the Indo-Pacific, but much rarer in the Red Sea.
Supply :
Like the tiger shark, the bulldog shark is omnivorous. He also eats cash sharks, than turtles marine, fish seawater oreau douce, calamari, mammals and birds. His only known predator is the crocodile, which he meets in the rivers.
Encounters with humans: The bulldog shark is considered very dangerous because it is involved in many attacks against humans, previously attributed to other species. He is at the origin of many aggressions in Brazil, on the island of Reunion and in Australia. In fact, even if the consequences of the attacks are impressive and highly publicized, the shark does little human casualties. These incidents occur mostly near the surface. It is in immersion that we can observe the risk factors related to his behavior, even if in the presence of scuba divers, the simple activity of the divers makes him flee rather than getting closer ...
Reputation :
Looking at the numbers and scientific analyzes, the Zambezi shark is in third place behind the Great White Shark (Carcharodons carcharias) and the Tiger Shark (Galeocerdo cuvier) as the most threatening shark to humans, due to its size, abundance in coastal areas with high human use and diet. In fact, it's responsible for around 80% of human bites each year, more than the white shark and tiger shark combined. Most of the victims are surfers and bathers. The few rare "fans" in scuba diving are the "feeders" who feed them by hand. The bulldog shark is sedentary, but evolves over a relatively large area. He is extremely territorial. Its biotopes - the living environment of an animal - are the areas of shallow depths, regularly stirred by the waves where we find part of its food chain thanks to the turpid waters such as: the coral reefs not far from the beaches , the outlets of estuaries, even the mouths where there is a strong industrial activity. They are also present near the coast where human activity is important - the hotel industry for example. Apart from major climatic changes, storms, strong currents, etc., the bulldog shark lives around these flourishing hunting areas. He is an extraordinary lone hunter.
Its method of predation is much the same as that of white sharks and tiger sharks. They swim along the seabed looking for a smell, noise or signal sent by possible prey. When he spots her, he very rarely does riding turns and quickly goes on the attack. It pounces on its prey at high speed from below, rarely giving it a chance to escape. It is an innate reaction following an interpretation biologically inscribed in its genes. Nothing to do with lions or tigers taken from any attraction for human flesh. Less fearful and more abundant on the coast than other sharks up to less than a meter deep, it is the most feared and feared of all underwater predators close to the coast! He is nevertheless docile, even shy in several regions of the world where he makes ecotourism flourish. Indeed, our terror of the seas turns out in scuba diving a creature difficult to approach without food!
Steven Surina
Steven Surina is a diving instructor in the Red Sea. In this capacity, for a decade, he has accompanied cruises along the Egyptian, Sudanese and Eritrean coasts. He worked in partnership with the Italian publishing house “Magenes Editoriale” on the project of a collection of dive sites all over the Egyptian Red Sea as an author and illustrator. He wrote a dissertation on the behavior of oceanic sharks in 2008 and distributed interactive booklets on the protection and preservation of sharks to Egyptian schools.
This is how he created, in 2010, Shark Education which offers shark diving trips whose objective is to help them get to know and understand them better.