Beaver Trivia
0Loading crowd target
0Loading crowd target
7correct to beat the crowd
This beaver trivia quiz has 55 free questions with answers and covers the animal from every angle: the biology (why the teeth are orange, how long a beaver can stay under, what the tail is really for), the engineering (the record dam in Alberta you can see from space, how fast a family rebuilds a broken one), the history (the felt-hat trade that nearly wiped out both species, the Hudson's Bay Company's 'made beaver' currency) and the culture, from Canada's nickel and first stamp to MIT's mascot, Oregon's two-sided flag and the beavers Idaho dropped from aeroplanes in 1948. The first questions are easy enough for a classroom or a family car ride; the back half will test a wildlife biologist. Every answer comes with a short explanation, so you leave knowing something you did not before. Every question has been checked against a primary source, mostly Wikipedia's beaver, castoreum and fur-trade articles, and shows its citation once you have answered.
30 of 55 questions with answers and explanations. Play the quiz
Q 01Which animal beats the beaver as the world's largest living rodent?
Capybara
The capybara of South America can top 60 kg; a big beaver reaches about half that.
Q 02What gives a beaver's front teeth their distinctive orange colour?
Iron compounds
The iron-hardened enamel sits on the front of the incisor, so the softer back wears faster and keeps the edge chisel-sharp.
Q 03When a beaver slaps its tail hard on the water, what is it doing?
Warning other beavers of danger
The slap is a warning to other beavers of danger: the crack carries a long way over water and usually sends the whole family diving for cover.
Q 04What kind of eater is a beaver?
Herbivore
Beavers are herbivores: bark, twigs, aquatic plants and sedges are the menu; the fish are just neighbours in the pond.
Q 05What are baby beavers called?
Kits
Baby beavers are kits; a litter of one to four is born each spring or summer after a gestation of roughly 105 days.
Q 06The beaver sits on a rock on the reverse of which Canadian coin?
The nickel
The G. E. Kruger Gray design has been on the nickel since 1937.
Q 07Which US state is nicknamed the Beaver State?
Oregon
The beaver is also Oregon's official state mammal and the mascot of Oregon State University.
Q 08Beavers' dome-shaped homes of sticks and mud are known as what?
Lodges
Beavers build lodges; the entrances are underwater, which is why they need a pond deep enough not to freeze solid.
Q 09The beaver genus name Castor comes from a word in which ancient language?
Greek
Castor comes from the Greek kastor, the word for beaver; Latin borrowed it and Linnaeus used it as the genus name in 1758.
Q 10At most, roughly how long can a beaver hold its breath underwater?
15 minutes
A beaver can stay under for up to 15 minutes; typical dives last five or six, and its heart rate halves while submerged.
Q 11How fast can a beaver swim?
About 5 mph (8 km/h)
Beavers swim at about 5 mph (8 km/h): the webbed hind feet do the work, and the flat tail acts as a rudder rather than a paddle.
Q 12The largest known beaver dam in the world is in which protected area?
Wood Buffalo National Park
Wood Buffalo National Park in northern Alberta holds the dam; Jean Thie spotted it on satellite imagery in 2007 before anyone had walked to it.
Q 13Roughly how long is the record beaver dam in northern Alberta?
850 m (2,790 ft)
The Wood Buffalo dam runs about 850 m (2,790 ft); it is absent from 1975 aerial photos, so generations of beavers built it in a few decades.
Q 21Besides steering and propping the animal upright, what does a beaver's flat tail store?
Fat
The tail stores fat for winter; a countercurrent blood system in it also dumps excess heat on hot days.
Q 22What protects a beaver's eyes while it swims underwater?
Nictitating membranes
Transparent nictitating membranes slide across the eyes like goggles; valves in the nostrils and ears close at the same time, sealing the head like a submarine hatch.
Q 23What did more than 27 Russian attempts to hybridise North American and Eurasian beavers produce?
A single stillborn kit
The only result was a single stillborn kit: North American beavers carry 40 chromosomes, the Eurasian species 48, so the two cannot interbreed.
Q 14A 652-metre beaver dam, 4.3 m high, was found near Three Forks in which US state?
Montana
The Three Forks dam in Montana was seven metres thick at the base, sturdier than many human levees.
Q 15How quickly can a beaver fell a tree about 15 cm (6 in) thick?
In under 50 minutes
A beaver can drop a 15 cm trunk in under 50 minutes; thicker trunks of 25 cm or more can keep it busy for hours.
Q 16Where do beavers store their winter food supply of cut branches?
In the deepest part of the pond
The cache goes in the deepest part of the pond; submerged wood stays fresh and reachable under the ice when the family cannot leave the water.
Q 17At what age do young beavers leave the family group to become independent?
Two years
Young beavers disperse at about two years old; as yearlings they stay on to help raise the next litter before leaving to find territory of their own.
Q 18In the wild, beavers usually live up to about how many years?
10
Wolves, coyotes, big cats and bears are the main predators of adults.
Q 19What is the split 'double nail' on a beaver's second hind toe used for?
Grooming the fur
The split nail is a comb for grooming the fur, which keeps the dense coat waterproof; a beaver's pelt packs up to 23,000 hairs per square centimetre.
Q 20What does a beaver's ability to close its lips behind its front teeth let it do?
Gnaw underwater without swallowing water
Lips sealed behind the incisors let a beaver gnaw underwater without swallowing water; the back of the tongue rises to form a second waterproof seal.
Q 24By the early 20th century, roughly how many Eurasian beavers survived across the whole of Eurasia?
About 1,200
About 1,200 survived, clinging on in just eight scattered populations between France and Mongolia.
Q 25By 2020, the Eurasian beaver population in Europe had recovered to what level?
More than one million
More than one million: reintroductions across the continent turned one of Europe's rarest mammals into a common one within a century.
Q 26The beavers released into Scotland's Knapdale forest in 2009 came from which country?
Norway
Norway had kept one of the few beaver populations that never died out in Europe.
Q 27How many North American beavers were released in Finland in 1937, a group that grew to 12,000 within 64 years?
7
Just 7 animals founded the population; by the 2000s the imported species outnumbered the native Eurasian beaver across much of Finland.
Q 28Which country's government imported beavers to Tierra del Fuego in 1946, hoping to start a fur industry?
Argentina
Argentina's government shipped in about 50 Canadian beavers in 1946; the fur business failed, the beavers thrived, and with no bears or wolves to eat them they have felled swathes of native forest.
Q 29Before European colonisation, roughly how many beavers are thought to have lived in North America?
100 to 200 million
Estimates put the pre-contact population at 100 to 200 million; by 1900 it was near zero, and the 21st-century recovery stands at roughly 10 to 15 million.
Q 30For centuries, European demand for beaver pelts was driven mainly by the making of what?
Felt hats
Felt hats: by the 1580s beaver 'wool' was the main raw material of French felt-hatters, and demand had already stripped most of western Europe's rivers of beavers.