50 free Hammerhead Shark trivia questions with answers — nature quiz, new questions added Aug 2026.
This hammerhead shark trivia quiz covers the strangest head in the sea: what the cephalofoil is for (360-degree vision, depth perception and a wider spread of electroreceptors), which of the ten species has the biggest hammer, how a great hammerhead pins a stingray with its head and swallows the barbs, why great hammerheads swim on their sides, and how the little bonnethead eats seagrass and reproduces without a male. It also covers the sharks and people: 17 unprovoked bites and zero deaths, the fin trade that puts 375,000 great hammerheads a year through Hong Kong, the 2013 CITES listing, the scalloped hammerhead as the first shark under the US Endangered Species Act, the beizam totem of the Torres Strait and the aumakua guardian sharks of Hawaii. Every question was verified against a primary reference (mainly the Wikipedia articles on the hammerhead family and its species) and carries a citation. Play it with our great white, whale shark and ocean quizzes.
30 of 50 questions with answers and explanations. Play the quiz
Q 01What is the scientific name for the hammerhead shark family?
Sphyrnidae
Sphyrna is Greek for hammer; Sphyraenidae, confusingly, are the barracudas.
Q 02What is the technical name for the hammerhead's flattened, T-shaped head?
Cephalofoil
The eyes sit at each end and the small mouth directly underneath in the middle.
Q 03Which hammerhead is the only species not placed in the genus Sphyrna?
The winghead
It has its own genus, Eusphyra, and proportionally the largest hammer of all.
Q 04How wide can the hammer of the Eusphyra species be, as a fraction of its body length?
Half
The species reaches only about 1.9 m long, so the hammer can span nearly a metre.
Q 05How many living hammerhead species are there?
Ten
They range from the 6 m great hammerhead to the 1.5 m bonnethead.
Q 06What field of vision does the eye placement on the hammer give in the vertical plane?
360 degrees
They can see above and below at all times, plus better binocular vision and depth perception.
Q 07Spreading electroreceptors across the wide head lets a hammerhead sweep for prey like what?
A larger radio antenna
The pores are the ampullae of Lorenzini, which detect the electric fields of living animals.
Q 08Which are the hammerheads' closest relatives?
The requiem sharks
That family, the Carcharhinidae, includes bull, tiger and blue sharks.
Q 09Definitive hammerhead fossils date back to which epoch?
The Eocene
Older DNA studies had put the family's origin in the Miocene, about 20 million years ago.
Q 10What is the largest hammerhead species?
Great
It averages about 4 m and 230 kg; the longest on record was 6.1 m.
Q 11What is the smallest hammerhead species?
Bonnethead
It tops out around 1.5 m and 11 kg, and is the hammerhead most often seen in public aquariums.
Q 12The heaviest known great hammerhead, caught off Boca Grande, Florida, in 2006, weighed how much?
580 kg
She was 4.4 m long and estimated at 40-50 years old, twice the typical lifespan.
Q 13How can you tell a great hammerhead's head from a scalloped hammerhead's?
Straight front edge versus a notched one
The smooth hammerhead has a rounded head with no notch at all.
Q 21How do hammerhead embryos get nourishment in the later stages of gestation?
Through a yolk-sac placenta
The depleted yolk sac transforms into a structure like a mammalian placenta.
Q 22How does a male hammerhead typically persuade a female to mate?
By biting her violently until she agrees
Reproduction happens only once a year.
Q 23In 2007, the smallest hammerhead became the first shark known to do what?
Reproduce asexually
A female at Nebraska's Henry Doorly Zoo produced a pup by automictic parthenogenesis, a perfect DNA match to its mother.
Q 14What is the great hammerhead's favourite prey?
Stingrays
One Florida specimen had 96 stingray spines lodged in and around its mouth and seemed untroubled.
Q 15How does a great hammerhead use its head when attacking a stingray?
To knock it down and pin it to the seabed
It then pivots to bite each pectoral fin, crippling the ray before sawing it apart with head shakes.
Q 16How many stingray spines were found in and around the mouth of one great hammerhead caught off Florida?
96
The venomous barbs do not seem to bother the shark.
Q 17A 2016 study found great hammerheads spend up to 90% of their time doing what to save energy?
Swimming on their side
'Rolled swimming' uses the tall dorsal fin for lift and cuts drag by about 10%.
Q 18Unlike most sharks, where have great hammerheads been observed mating?
Near the surface
A Bahamas pair spiralled upward around each other and mated on reaching the surface.
Q 19How long is a great hammerhead's gestation?
11 months
Females breed every two years; litters run 6-55 pups, typically 20-40, each 50-70 cm long.
Q 20What is the typical litter size for most hammerhead species?
12 to 15 pups
The great hammerhead is the exception with 20 to 40; pups get no parental care and huddle together in warmer water.
Q 24What surprising food makes up as much as half the stomach contents of some of the smallest hammerheads?
Seagrass
They can partially digest it, making the bonnethead the first shark shown to be omnivorous.
Q 25The smallest hammerhead is the only shark known to show sexual dimorphism in what?
The shape of its head
It is also called the shovelhead for its spade-like cephalofoil.
Q 26Which other species was later found to be omnivorous, after the smallest hammerhead?
The whale shark
For a while the bonnethead was the only known case.
Q 27What unusual social behaviour do some hammerheads show by day?
Swimming in large schools
Scalloped hammerheads gather in schools of hundreds, then split up to hunt alone at night.
Q 28Tagged scalloped hammerheads migrate between Cocos Island and mangroves in which Costa Rican fjord?
Golfo Dulce
Juveniles thrive in shallow bays and mangroves that shelter them from predators.
Q 29The scalloped hammerhead was the first shark protected under which law?
The US Endangered Species Act
It has been Critically Endangered on the IUCN Red List since 2019.
Q 30How does the IUCN classify the great hammerhead as of 2019?
Critically Endangered
Its large fins are prized for shark fin soup, and its low abundance and long generation time make it hard to recover.