- Yes, there are sharks in the Amazon River.
- There is one shark species inhabiting the Amazon River–the bull shark.
The Amazon River is the largest river by volume in the entire world. With such a massive waterway, is it possible that any sharks have made their way into it? Incredibly, there is a species of shark that hasn’t just one it before but is regularly caught in the Amazon. Today, we are going to answer the question, “are there sharks in the Amazon River?”
Are there sharks in the Amazon River?
The only species of shark that lives in the Amazon River is the bull shark.
Although we generally consider freshwater to be safer than the ocean, that isn’t always the case! The Amazon River is the largest river in the world (by volume) and is home to a very dangerous shark. In fact, many rivers in the world are home to this top predator that most people consider to be ocean-dwelling.
The bull shark is a species of shark that is known to head into freshwater with regularity. In the Amazon, bull sharks are often caught upriver after they head inland from the ocean. These sharks are known to live in salt, fresh, and brackish waters and have been caught in rivers, estuaries, lakes, and more. Since they live in the Atlantic around the entrance to the Amazon River, they often head deep into it.
How far do sharks travel up the Amazon?
In the Amazon, bull sharks have been sighted as far as 2,500 miles inland. The furthest inland sighting from the Amazon was documented all the way to Iquitos, Peru. Iquitos is a port city on the Amazon River that is quite literally in the middle of the jungle. For reference, Peru is a country that is located on the Pacific side of South America, requiring a bull shark to traverse nearly the entire width of the continent.
Although Iquitos is the furthest inland that a bull shark has been found in the Amazon, it is rare for them to travel that far. Still, they are incredibly common around the entrance to the Amazon and even a few hundred miles inland. Fishermen are known to occasionally catch these large sharks while fishing on the river quite a distance from the ocean.
What’s the furthest from the ocean a shark has ever been spotted?
Currently, the bull shark that was sighted in Iquitos, Peru, is the furthest inland a bull shark has even been recorded. Still, there are plenty of other examples of just how far they can travel through freshwater systems.
In the United States, bull sharks often travel up the Mississippi River and head north. The furthest north that a bull shark has been recorded in the Mississippi is in Alton, Illinois. Alton is 15 miles north of St. Louis and 1,750 miles north of the Gulf of Mexico, where the sharks usually live. Additionally, bull sharks have been seen in the Ohio River as far north as Manchester, Ohio, and in the Potomac River in Maryland.
Australia is also home to bull sharks. After the flooding of the Logan and Albert Rivers in 1996, a group of sharks was trapped in golf course lakes at the Carbrook Golf Club in Queensland, Australia. Now, they are permanently living in the lakes, with the Shark Lake Challenge tournament being named after the population.
How do bull sharks live in freshwater?
Part of what makes bull sharks so adaptable is their evolutionary adaptations and freshwater tolerance. Only a few species of fish are able to switch between fresh and salt water, with the bull shark being among them. This advantage likely occurred during the last ice age when there was a population bottleneck.
Bull sharks can live in freshwater through specialized organs like the rectal gland and an adapted kidney, liver, and gills. In saltwater, bull sharks excrete excess salt through their rectal glands but reduce this action while in freshwater. If needed, a bull shark can live its entire life in freshwater, even so far as to reproduce in it!
Are bull sharks dangerous to humans?
Bull sharks are incredibly dangerous to humans if they are in the same area. They are among the most dangerous sharks in the world by number and are known for their aggressive nature. In fact, part of what gives bull sharks their name is their tendency to ram a target before biting it. They generally prefer dark, murky waters to hunt and will eat almost anything they can find.
If you are swimming in the ocean, bull shark encounters are much more likely. Although they do travel into river systems, the likelihood of being attacked by one is quite low. If you are taking regular dips into the Amazon, there are likely other, more serious threats you should be concerned about!
Are there dolphins in the Amazon?
Although there are sharks in the Amazon, there are also dolphins! Where bull sharks are naturally saltwater-dwelling fish, the Amazonian dolphins are actually native to the freshwater regions of the river. These dolphins, known as the boto, or pink river dolphin, are a species of whale that live through large expanses of the Amazon River, roughly covering 2,700,000 sq miles across multiple countries. They generally live in river basins, major courses of rivers, canals, river tributaries, lakes, and at the ends of rapids and waterfalls.
The photo featured at the top of this post is © worldclassphoto/Shutterstock.com
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