Hammerhead sharks
About ten species of shark with a hammer for a head, from the solitary great hammerhead to the scalloped hammerheads that school in their hundreds at offshore islands.
The three large hammerheads
Scalloped hammerhead
Sphyrna lewini · Critically Endangered
The schooling hammerhead, aggregating in the hundreds by day at offshore islands such as the Galápagos and making deep dives at night, probably to feed.
Species profile →Great hammerhead
Sphyrna mokarran · Critically Endangered
The largest hammerhead, a generally solitary hunter of stingrays; the largest measured in recent Florida and Australian studies were about 4.5 meters (15 feet).
Species profile →Smooth hammerhead
Sphyrna zygaena · Vulnerable
The most oceanic hammerhead, ranging farther into cool, temperate seas than the scalloped and great hammerheads.
Species profile →
The six other hammerheads on the IUCN Red List, from the bonnethead to the winghead shark, are covered in Types of Hammerhead Shark. Start with our hammerhead shark facts, or go deeper in The Complete Guide to Hammerhead Sharks.
MMF and hammerheads
- MMF scientists meet scalloped hammerhead schools at Darwin and Wolf islands in the Galápagos, where Dr. Alex Hearn and colleagues tagged more than 100 hammerheads between 2006 and 2009. His team at the Universidad San Francisco de Quito leads the silky shark tracking study that MMF scientists contribute to, and led the completed yellowfin tuna study in the Galápagos.
- An MMF co-founder co-assessed the scalloped, great, and smooth hammerheads for the 2019 IUCN Red List. The assessments classify the scalloped and great hammerheads as Critically Endangered and the smooth hammerhead as Vulnerable.
- We co-authored the 2022 global study of shark and ray depth use, which included 17 tagged scalloped hammerheads. They consistently used relatively shallow water across regions, a pattern the authors say could allow generalized fisheries management approaches where data are too limited for regional management.
The Complete Guide to Hammerhead Sharks
Types of hammerheadTypes of Hammerhead Shark: How Many Species, and How to Tell Them Apart
Why the hammer?Why Do Hammerhead Sharks Have a Hammer? What the Science Says About the Cephalofoil
SizeHow Big Are Hammerhead Sharks? Size by Species, Pups, and Records
Feeding and dietWhat Do Hammerhead Sharks Eat? Diet and Hunting by Species
Schooling and migrationWhy Do Hammerhead Sharks School, and Where Do They Migrate?
Baby hammerheadsBaby Hammerhead Sharks: Pups, Nurseries, and Reproduction
Threats and conservationWhy Are Hammerhead Sharks Endangered? Threats and Conservation
Are hammerheads dangerous?Are Hammerhead Sharks Dangerous? Diving and Swimming with Hammerheads
Protect the ocean's hammerheads
Your gift supports MMF's shark research, including our part in the partner-led silky shark tracking study in the Galápagos.
