Amazon River Dolphin
0Loading crowd target
0Loading crowd target
6correct to beat the crowd
40 free Amazon River Dolphin trivia questions with answers — trivia quiz, new questions added Oct 2026.
The Amazon river dolphin, or boto, is the pink dolphin of South America's rainforest rivers, and almost everything about it is a fun fact. It changes colour as it grows up, steers through places no ocean dolphin could go, and courts with props. River people have told stories about it for centuries. This quiz turns the best pink dolphin facts into questions: the body and senses that suit life in muddy water, what botos eat and who hunts beside them, how they raise their young, the legends told along the riverbank, and the dangers the species now faces from people. It is written for curious readers, classrooms and trivia nights rather than specialists. The opening questions are the famous facts, later ones dig a little deeper, and every answer comes with a short explanation.
30 of 40 questions with answers and explanations. Play the quiz
Q 01Amazon river dolphins turn pinker with age; what is believed to give adult males their rosy colour?
Scar tissue
Scar tissue builds up over years of fights and rough play, so battle-worn males end up the pinkest. Females are thought to prefer the brighter ones.
Q 02In Amazon folklore, a river dolphin comes ashore at night as a charming man wearing what to hide his blowhole?
A hat
A hat covers the one feature the shapeshifter cannot change. In the tales he loves a party, then hurries back to the water by morning to become a dolphin again.
Q 03Which part of the Amazon river dolphin's body bends unusually far because its vertebrae there are not fused?
Neck
Neck bones that stay separate let the dolphin turn its head 90 degrees to chase fish around tight obstacles. Ocean dolphins have fused ones and cannot.
Q 04Male Amazon river dolphins have been seen rolling belly-up to launch what into the air for other males to chase?
A stream of urine
A stream of urine is fired skyward while another male tracks it with his snout, behaviour that researchers think may pass on chemical signals.
Q 05Which ocean predator, famed for swimming far up rivers, is thought capable of preying on Amazon river dolphins?
Bull shark
Bull shark jaws are a rare danger because the species thrives in both salt and fresh water. Even so, no natural predator of the dolphin has ever been recorded.
Q 06Each rainy season, Amazon river dolphins leave the main river channels to hunt in which habitat?
Flooded forests
Flooded forests become a vast seasonal sea where the dolphins weave between tree trunks after fish. Mothers and calves linger there longest, away from the main channels.
Q 07Which notorious Amazon fish, from the family Serrasalmidae, is a regular part of the Amazon river dolphin's diet?
Piranhas
Piranhas are only one item on a famously varied menu that takes in dozens of fish species, from croakers and cichlids to tetras.
Q 08Curious wild Amazon river dolphins have been reported grabbing hold of what belonging to passing fishermen?
Canoe paddles
Canoe paddles are a favourite plaything, and the dolphins also rub against boats and toss sticks and logs about. In captivity they proved bolder than bottlenose dolphins.
Q 09River dolphins, like every whale, are most closely related to which large land animals living in Africa today?
Hippopotamuses
Hippopotamuses and whales descend from a shared semi-aquatic ancestor, which makes dolphins distant cousins of hoofed mammals such as cattle and deer.
Q 10What colour is a newborn Amazon river dolphin, years before it develops the famous adult blush?
Dark grey
Dark grey calves fade to a lighter shade in adolescence, and only adults go pink. Even then, some keep a darker back.
Q 11Which title does the Amazon river dolphin hold among the world's river dolphins?
Largest
Largest of all the river dolphins, a big male can weigh as much as two adult people. Unusually for river dolphins, the males grow bigger than the females.
Q 12Unlike whales of cold seas, the Amazon river dolphin has only a thin layer of what beneath its skin?
Blubber
Blubber keeps ocean whales insulated, shields them and stores energy, needs that barely arise in a warm, shallow river, so river dolphins carry only a thin layer.
Q 13Which toxic metal, washed into Amazon rivers by gold mining, has been found in river dolphins' muscle and milk?
Mercury
Mercury reaches the water mainly through illegal gold mining and builds up in fish-eaters, so scientists use the dolphins as sentinels of the river's health.
Q 21Beyond the Amazon basin, Amazon river dolphins also live throughout which great river system of Venezuela and Colombia?
Orinoco
Orinoco animals were proposed as a subspecies of their own in 1977, though genetic work suggests they descend from Amazon dolphins and barely differ.
Q 22Which naturalist reported on pink river dolphins while exploring Venezuela's rivers with botanist Aimé Bonpland in 1800?
Alexander von Humboldt
Alexander von Humboldt set out to prove that South America's rivers interlock, and he was right: a natural channel joins the two great basins where the dolphins live.
Q 23Since about 2000, Amazon river dolphins have been illegally killed and used as bait to catch which kind of fish?
Catfish
Q 14What human-built barriers threaten Amazon river dolphins by splitting their populations and blocking migrating fish?
Hydroelectric dams
Hydroelectric dams cut one population into small groups that can no longer interbreed, and they stop the fish migrations that feed the dolphins downstream.
Q 15Amazon river dolphins have been seen herding fish in coordinated hunts with which other Amazon predators?
Giant otters
Giant otters and the dolphins round up shoals together, and the partners barely compete because each prefers different kinds of fish.
Q 16What do male Amazon river dolphins carry in their mouths and wave about in displays linked to mating?
Floating branches
Floating branches or balls of hardened clay are carried mostly when many adults gather, and the show seems aimed at females while stirring up fights between rival males.
Q 17Which fatty organ in the Amazon river dolphin's bulging forehead can be reshaped by muscle to focus its sonar clicks?
The melon
The melon is a mass of fat that works as a sound lens, shaping clicks into a beam. A hunting boto fires 30 to 80 clicks a second into the murky water.
Q 18Which of the five classic senses do river dolphins appear to lack entirely, as their brains have no lobes for it?
Smell
Smell seems to be missing because river dolphins have no olfactory lobes. Taste may be weak too, since their taste buds are shrunken or absent.
Q 19Which smaller dolphin shares the Amazon's rivers with the Amazon river dolphin yet belongs to the ocean dolphin family?
Tucuxi
Tucuxi look like small bottlenose dolphins, about 1.5 metres long, and although they live in fresh water they are not closely related to the boto.
Q 20Which South American country passed a law in 2012 declaring its pink river dolphins a national treasure?
Bolivia
Bolivia's president Evo Morales enacted the law to protect the dolphins, which live in the upper Madeira River basin and are counted as a subspecies of their own.
Catfish called piracatinga are scavengers drawn to rotting flesh, and growing demand for them turned dolphin carcasses into something fishermen could sell.
Q 24In 2018 the IUCN Red List moved the Amazon river dolphin into which threat category, citing a falling population?
Endangered
Endangered status reflects deaths in fishing lines and at the hands of bait hunters, on top of pollution. Captive breeding is not seen as a way to save the species.
Q 25Local legends call the Amazon river dolphin the guardian of which other gentle water mammal of the same rivers?
Manatee
Manatee hunters, the stories say, must first make peace with the dolphin, and harming the guardian itself is held to bring bad luck.
Q 26What name is given to the shapeshifting river dolphin of Amazon folklore, said to seduce villagers at night parties?
Encantado
Encantado is Portuguese for 'charmed'. The beings are said to come from an underwater paradise without pain or death, yet they crave human company.
Q 27In which European country did an Amazon river dolphin named Baby live in one zoo for more than 45 years?
Germany
Germany's Duisburg Zoo kept Baby until he died in December 2020, aged at least 46. Most captive botos fared far worse, lasting under three years on average.
Q 28Chuckles, the last Amazon river dolphin kept in the United States, died in 2002 at which city's zoo?
Pittsburgh
Pittsburgh's last river dolphin, Chuckles, reached the age of 34, though most of the dolphins flown to American aquariums died within a few years.
Q 29The Amazon river dolphin belongs to which major group of cetaceans, alongside orcas, porpoises and narwhals?
Toothed whales
Toothed whales hunt one prey animal at a time using sonar instead of filtering the sea, and the boto has around a hundred teeth in two different shapes.
Q 30Besides fish and crabs, which armoured reptiles can the Amazon river dolphin crack open with its molar-like back teeth?
Turtles
Turtles are on the menu because the boto, unlike most dolphins, has two kinds of teeth: pointed ones in front to grip and ridged ones behind to crush.