Freshwater Animals Quiz

1. Which large South American river mammal uses echolocation to navigate murky river water?

1. Amazon manatee
2. Amazon river dolphin (boto)
3. Capybara
4. Giant otter

2. The beaver is famous for building dams. Why do beavers build dams?

1. To collect fish more easily
2. To create a deep pond around their lodge for protection from predators and to store food underwater
3. To create a food storage area for winter
4. To mark their territory against rival beavers

3. Which fish is famous for swimming thousands of kilometres upriver to spawn in exactly the same place where it was born?

1. Catfish
2. Pike
3. Salmon
4. Trout

4. The electric eel lives in South American rivers. Despite its name, what kind of fish is it?

1. It is a knifefish, more closely related to catfish than true eels
2. It is a true eel (order Anguilliformes)
3. It is a type of lamprey
4. It is an electric ray that lives in freshwater

5. Which large freshwater reptile found in Africa and Asia ambushes prey from the water's edge?

1. Alligator
2. Anaconda
3. Monitor lizard
4. Nile crocodile

6. The hippopotamus is the third-largest land animal. How much of its day does it spend in water?

1. About 25% of the day
2. About 50% of the day
3. About 75-80% of the day
4. Almost 100% — hippos almost never leave water

7. Which colourful freshwater bird dives into rivers to catch fish and is known for its vivid plumage?

1. Cormorant
2. Dipper
3. Heron
4. Kingfisher

8. The water otter is famous for a charming behaviour. What do otters use their chests for while floating?

1. As a table to balance food, and mother otters wrap their pups in kelp while they dive
2. To communicate by thumping their chest on the water surface
3. To regulate body temperature by exposing their lighter belly
4. To store fish caught during diving

9. Which South American freshwater fish hunts in large schools and is famous (perhaps unfairly) for its aggressive feeding behaviour?

1. Arapaima
2. Pacu
3. Peacock bass
4. Piranha

10. What is the largest freshwater fish in the world?

1. Arapaima
2. Mekong giant catfish or Beluga sturgeon (both disputed)
3. Nile perch
4. Wels catfish

11. The water vole is a small rodent that lives along British rivers. What made it nearly extinct in the UK?

1. Flooding due to climate change
2. Habitat loss from river management
3. Pollution from agriculture
4. The introduction of American mink — a non-native predator that hunts water voles along riverbanks

12. Which unusual freshwater mammal from Australia can sense prey using electrical receptors in its bill?

1. Echidna
2. Platypus
3. Quokka
4. Water rat (Rakali)

13. The great crested newt is a freshwater amphibian protected by law in the UK. Why does the male grow a jagged crest?

1. As a defence against predators — the crest is toxic
2. As a sexual display to attract females during the spring breeding season
3. For hydrodynamic efficiency when swimming fast
4. To regulate body temperature like a sail

14. Giant river otters in the Amazon can reach 1.8 metres long. How do they hunt?

1. Alone, silently stalking fish from riverbanks
2. By diving and holding their breath for up to 8 minutes
3. In coordinated family groups, herding fish cooperatively
4. Using tools to dislodge fish from hiding places

15. Which African freshwater giant, related to pigs and whales, is considered the most dangerous large mammal in Africa?

1. African buffalo
2. Elephant
3. Hippopotamus
4. Nile crocodile

16. The freshwater pearl mussel is one of Britain's rarest animals, requiring extremely clean water. How long can it live?

1. Up to 130 years
2. Up to 15 years
3. Up to 30 years
4. Up to 300 years

17. The dipper is a remarkable small bird found along fast-flowing streams. What makes it unique among songbirds?

1. It is the only British songbird that migrates to Africa
2. It is the only songbird that builds its nest underwater
3. It is the only songbird that can sing underwater
4. It is the only songbird that regularly walks underwater along stream beds to find food

18. Lake Baikal in Russia is remarkable for its freshwater wildlife. What percentage of its species are found nowhere else on Earth?

1. About 20%
2. About 40%
3. About 60%
4. About 80%

19. Which South American freshwater turtle can stay completely submerged for months during dry season?

1. Matamata turtle
2. Red-eared slider
3. South American river turtle (arrau)
4. Yellow-spotted river turtle

20. Why do dragonfly nymphs live underwater for months or years before becoming adult dragonflies?

1. The aquatic larval stage is their main feeding and growth phase — they are voracious underwater predators before emerging
2. They need clean water to develop their wings properly
3. They need to learn to breathe before they can survive in air
4. Water protects their developing wings from drying out