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Scalloped Hammerhead
Sphyrna lewini
Silhouette: PhyloPic
- KingdomAnimalia (Animals)
- PhylumChordata (Chordates)
- ClassElasmobranchii
- OrderCarcharhiniformes (Ground Sharks)
- FamilySphyrnidae (Hammerhead and Winghead Sharks)
- GenusSphyrna (Hammerhead Sharks)
- SpeciesSphyrna lewini (Scalloped Hammerhead)
In 3 days >90%
28 Verified sightings at Isla del Coco National Park From 2019 to 2026
243 In all 2 parks
January Best month
☀️ Diurnal When it's spotted
About the Scalloped Hammerhead
The scalloped hammerhead (Sphyrna lewini) is a species of hammerhead shark in the family Sphyrnidae. It was originally known as Zygaena lewini. The Greek word sphyrna translates into "hammer" in English, referring to the shape of this shark's head, which is its most distinguishing characteristic. The shark's eyes and nostrils are at the tips of the extensions. It is a fairly large hammerhead, but is still smaller than both the great and smooth hammerheads.
This shark is also known as the bronze, kinky-headed, or southern hammerhead. It primarily lives in warm, temperate, and tropical coastal waters all around the globe between latitudes 46°N and 36°S, down to a depth of 500 m (1,600 ft). It is the most common of all hammerheads.
The scalloped hammerhead was first named Zygaena lewini and then renamed Sphyrna lewini by Edward Griffith and Hamilton Smith in 1834. It has also been named Cestracion leeuwenii by Day in 1865, Zygaena erythraea by Klunzinger in 1871, Cestracion oceanica by Garman in 1913, and Sphyrna diplana by Springer in 1941. Sphyrna comes from the Greek and translates to hammer.
It is a sister species to Sphyrna gilberti, differing by the number of vertebrae... Wikipedia →
Recent sightings of Scalloped Hammerhead in Isla del Coco National Park
LIVEiNaturalistGlobal Distribution
Parks Where Found
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Isla del Coco National Park | 🇨🇷 Costa Rica | |
| 2 | Galápagos Islands | 🇪🇨 Ecuador |
Zoos & Centres Where Found
Closest Relatives at Isla del Coco National Park
Before you go
What are the chances of seeing a Scalloped Hammerhead in Isla del Coco National Park?
Very likely
About 80% of wildlife watchers report a Scalloped Hammerhead sighting in Isla del Coco National Park on a given day, based on 28 verified sightings from GBIF citizen-science data from 2019 to 2026. Over three days the chance rises to over 90%, if each day is a fresh chance.
When is the best time to see a Scalloped Hammerhead in Isla del Coco National Park?
January
In that month about 90% of wildlife watchers report a Scalloped Hammerhead in Isla del Coco National Park on a given day, against about 30% in June and July, the lowest months. February, April–May and August–October have too few records to rate.
What time of day is best to see a Scalloped Hammerhead?
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Scalloped Hammerhead sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Is Isla del Coco National Park the best place to see a Scalloped Hammerhead?
Yes
Of the 2 parks where we can rate Scalloped Hammerhead sightings, Isla del Coco National Park has the highest daily chance: about 80%. Next come Galápagos Islands (Ecuador, about 40%).
Which relatives of the Scalloped Hammerhead live in Isla del Coco National Park?
Same order: Carcharhiniformes
The closest relatives of the Scalloped Hammerhead that you can see in Isla del Coco National Park (order Carcharhiniformes, Ground Sharks) are Whitetip Reef Shark (about 90%) and Galápagos Shark (about 50%), with each one's daily chance of a sighting.
Where does the Scalloped Hammerhead sighting chance come from?
GBIF citizen-science records
It is estimated from how often the Scalloped Hammerhead is recorded against all the sharks and rays logged in Isla del Coco National Park (28 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
