Eight amazing records held by the Amazon River

By Aliciamarie Rodriguez
Published
aerial view of the amazon river

The Amazon River is one of the most complex and vital water systems in the world.

Its massive amount of water feeds the adjoining Amazon Rainforest, makes it impossible to build bridges over and raises the height of the ocean in the Caribbean Sea.

The Amazon River's role as a global freshwater powerhouse, its geologic past, special wildlife and impact on ecosystems in the region make this river one of the most fascinating places on Earth. 

It nurtures the largest rainforest in the world and provides life for a vast array of flora and fauna.

Despite centuries of exploration, it's still a magical place that houses many secrets.

In celebration of Earth Day, we’ve rounded up some of the most interesting records that make the mighty Amazon one of the wonders of the world.

aerial-view-of-the-amazon-river

Widest and greatest river (by flow rate)

The Amazon River has the largest volume of fresh water of any river in the world and is the greatest river (by flow rate). 

It discharges an average of 200,000 cubic metres per second (7,100,000 cubic feet per second) into the Atlantic Ocean, increasing to more than 340,000 cubic metres per second (12,000,000 cubic feet per second) in full flood. 

The lower 1,450 km (900 miles) average 17 m (55 ft) in depth, but the river has a maximum depth of 124 m (407 ft). 

While not in flood, the river’s main stretches can reach widths of up to 11 km (7 miles), also making it the widest river in the world.

The outflow of water produced each day generates enough power to keep New York City supplied with electricity for nearly a decade. Talk about power!

Together, this freshwater flow accounts for nearly 20% of all river water that enters the sea. Its flow is also 60 times greater than that of the Nile. 

Largest species of river dolphin

Known for its innumerable wildlife species, the Amazon River is the habitat for the largest species of river dolphin, which can attain a length of up to 2.6 m (9 ft). 

Famed for its unique pink colouration, the boto (Inia geoffrensis), also known as the Amazon River dolphin or pink river dolphin, is one of only four "true" river dolphin species.

Unlike their marine cousins, Botos live exclusively in freshwater habitats. 

Although Botos appear light grey in color, they flush pastel pink when excited - just like a human blushing! This colour-changing characteristic historically spared them from human persecution because of the belief that it was a special power.

The striking freshwater mammal is also the dolphin with the most hair, with bristles on its snout acting as a sensory device in feeling for food on the muddy river bottoms. While ocean dwelling dolphins lose the hairs on their rostrum shortly after birth, Botos keep their hair into adulthood. 

Once abundant in the waters of the Amazon and Orinoco rivers of South America, Botos are now considered an endangered species due to recent population declines resulting from human activity.

Boto populations are hurt by the damming and contamination of the Amazon River and are killed by fishermen for use as bait to catch catfish.

The World Wildlife Foundation is working to support the Regional Conservation and Management Plan for River Dolphins in Brazil, Colombia, Ecuador and Peru to increase collaboration between the four countries and conserve the unique freshwater dolphin.

black-caiman-with-its-mouth-wide-open

Largest caiman species

The black caiman (Melanosuchus niger) is not only one of the largest predators in the Amazon ecosystem, but also the largest caiman species of the six alive today.

Native to rivers and swamps in the Amazon basin, including parts of Brazil and neighbouring countries, this alligator-related crocodilian can sometimes exceed 5 m (16.4 ft) long and 400 kg (881.8 Ibs) in weight.

The carnivorous reptile feels right at home in the Amazon River, preying on its massive supply of fish, reptiles, birds, and mammals as large as capybaras or jaguars!

Superficially it looks like the American alligator and its protective armoured skin, as its name suggests, is dark in color. 

Long hunted for it's valuable skin, its scutes help the black caiman camouflage during nocturnal hunts and help to absorb heat. 

The black caiman is highly feared for being one of the topmost predators of the Amazon River, with more than 80 attacks on humans in the past two decades alone.

bull-shark-swimming-through-the-water

Shark species farthest from the sea

The vast majority of shark species are exclusively marine in habitat, but the bull shark (Carcharhinus leucas) is a rare yet very notable exception. 

In a river already harbouring caiman, piranhas, anacondas and plenty of other tropical species, who would have thought that bull sharks would be something to worry about.

Bull sharks prefer coastal waters less than 30 metres (98.4 feet) deep, especially in areas such as river mouths where there is plenty of freshwater inflow. 

On many occasions bull sharks have been known to venture out of their normal habitat and into completely freshwater environments.

For this reason, they have often been spotted in the Amazon River and are the shark species farthest from the sea.

Most shark species cannot survive in freshwater because their bodies need a certain amount of salt retention to survive. Without salt, their cells would burst, causing them to bloat and die.

Bull sharks have unique adaptations which allow them to live in freshwater environments for extended periods of time. 

Their "osmoregulating" kidneys can inhibit the excretion of vital salts by sensing the change in the water’s salinity. 

Bull sharks also have glands near their tails which assist them in retaining salt levels.

This has allowed the Bull shark to turn up in some surprising places, most notably the Ganges, Mississippi, and Amazon rivers.

Although this may sound like the plot to a horror movie, there’s no need to fear. 

Bull sharks tend to feed on the Amazon River’s vast supply of fish, turtles, birds and any other Bull sharks that might get in their way.

Keep an eye out for any fins making their way through the Amazon. They may not belong to the Boto!

electric-eel-swimming-through-river-grass

Most electric fish

The Piranha may have earned itself a reputation as a fearful predator, but it shares its home with another threatening fish.

The electric eel, or poraquê (Electrophorus) is native to the Amazon River and is not only the most electric fish but is also the most electric animal in the world.

Since it was first identified, the electric eel was thought to be a single species, but an additional two species were found in 2019: E. voltai and E. varii.

All electric eels can grow to 1.8 metres (5 feet 10 inches) long – though larger ones are occasionally spotted.

These shocking fish are capable of producing electricity thanks to three dedicated paired organs – the main, Hunter’s and Sach’s organs – distributed across their elongated bodies. 

"Electrocyte" cells in these organs create charges by moving sodium and potassium around.

The eels can trigger these shifts at a moment's notice to send the charges from thousands of electrocytes into an object or creature.

The highest discharge reported for an electric eel is between 550 and 650 volts. 

That’s about the same electrical output as a domestic microwave, or several times the voltage of a standard electrical socket!

Additional Amazon River records

It's not just the Amazon's waters that hold impressive record titles. 

Over the years, multiple people have braved the mystic waterway in an attempt to make their way into the record books.

Some of the most notable include: 

  • First row of the navigable length of the Amazon River - The first people to row the navigable length of the Amazon River are Mark de Rond (Netherlands) and Anton Wright (UK), who embarked from Nauta in Peru on 13 September 2013 and rowed to Macapá in Brazil, arriving on 15 October 2013.
  • First person to walk the length of the Amazon River - The first person to walk the length of the Amazon River was Ed Stafford (UK) and he completed the trip in 2 years, 4 months and 8 days (860 days), finishing on 9 August 2010.
  • First to kayak/raft the full length of the Amazon River (from source area to the Atlantic Ocean) - The first explorers to paddle the full length of the Amazon was achieved by Piotr Chmielinski (Poland) and Joe Kane (USA), on the 19 February 1985.
  • Longest journey swimming (open-water) - The longest journey swimming is 5,268 km (3273.38 miles) and was achieved by Martin Strel (Slovenia) who swam the entire length of the Amazon River, Peru/Brazil, from 1 February to 8 April 2007.
  • Longest time to pogo stick jump underwater - In 1987, in 3 hours 40 mins, Ashrita Furman bounced 3,647 times in the Amazon River in Peru.

Conserving the Amazon

Today, the Amazon faces a threat bigger than any of the deadly species lurking in its waters.

Some lawmakers have relaxed protection laws for the Amazon Rainforest, favouring agricultural interests over those of indigenous Amazon reserves, putting the majestic river at risk of having its magic depleted.

Historically, indigenous inhabitants of the region have protected the Amazon, relying on its resources to survive.

As they stand against deforestation, mining, and oil drilling, there are things we can each do individually to preserve this precious natural asset, including: 

  • Reducing meat consumption
  • Reducing the use of wood and paper
  • Supporting Rainforest Action Groups
Together, we can protect one of Earth's greatest treasures.