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Scalloped Hammerhead Shark

Scalloped Hammerhead Shark

Sphyrna lewini

640x427-scalloped-hammerhead.png

Protected Status

ESA Endangered
Eastern Pacific DPS
ESA Endangered - Foreign
Eastern Atlantic DPS
ESA Threatened
Central & Southwest Atlantic DPS
ESA Threatened
Indo-West Pacific DPS
CITES Appendix II
Throughout Its Range

Quick Facts

Weight
Up to 335 pounds
Lifespan
Up to 30 years
Length
Up to 11 feet
Threats
Overfishing, Bycatch
Region
Pacific Islands, Southeast, West Coast, Foreign
See Regulatory Actions
scalloped_hammerhead_shark.jpg Scalloped hammerhead shark - Photo: NOAA Fisheries

Scalloped hammerhead shark - Photo: NOAA Fisheries

About the Species

Scalloped hammerhead sharks are moderately large sharks with a global distribution. The most distinguishing characteristic of this shark is its "hammer-shaped" head. They are threatened by commercial fishing, mainly for the shark fin trade. Two distinct population segments of the scalloped hammerhead shark are listed as endangered and two are listed as threatened under the Endangered Species Act (ESA).

NOAA Fisheries is committed to conserving and protecting scalloped hammerhead sharks. Our scientists and partners use a variety of innovative techniques to study and protect this species.

Protected Status

ESA Endangered

  • Eastern Pacific DPS

ESA Endangered - Foreign

  • Eastern Atlantic DPS

ESA Threatened

  • Central & Southwest Atlantic DPS

ESA Threatened

  • Indo-West Pacific DPS

CITES Appendix II

  • Throughout Its Range

Scientific Classification

Kingdom Animalia
Phylum Chordata
Class Chondrichthyes
Order Carcharhiniformes
Family Sphyrnidae
Genus Sphyrna
Species lewini

Featured News

An approximately 3-foot-long small shark is laid belly down on the deck of a vessel by a scientist wearing thick rubber boots and gloves. The shark’s eye and top (dorsal) and side (pectoral) fins are clearly visible. The shark is light colored on its belly side and has a pattern of dark and light gray colors on its body that look like stripes. Small tiger shark captured for tagging and release 2021 Coastal Shark Survey. Credit: NOAA Fisheries/Apex Predator Program.
Feature Story

2021 Coastal Survey Catches Nearly 2,500 Atlantic Sharks

New England/Mid-Atlantic
Shark And Remora Fish
Feature Story

How Our Shark Finning Ban Helps Us Sustainably Manage Shark Fisheries

New England/Mid-Atlantic
Southeast
Pelagic Blacktip shark in open water . Pelagic blacktip shark in open water. Credit: Madelein_Wolf/Getty Images
Feature Story

U.S.-Caught Sharks Are a Sustainable Food Choice

New England/Mid-Atlantic
Southeast
shark_cruise_26.jpg
Feature Story

Fishing for Sharks in the Gulf of Mexico

Southeast
View More News

In the Spotlight

Management Overview

Two distinct population segments of the scalloped hammerhead shark are listed as endangered and two are listed as threatened under the Endangered Species Act (ESA).

Regulatory History

On August 14, 2011, NOAA Fisheries received a petition from WildEarth Guardians and Friends of Animals to list the scalloped hammerhead shark as threatened or endangered under the ESA throughout its entire range, or as an alternative, to delineate the species into distinct population segments. On November 28, 2011, we published a notice that listing may be warranted. We published the proposed rule to list under the ESA and a status review of the species in April 2013. In July 2014, we listed four distinct population segments under the ESA.

Key Actions and Documents

Actions & Documents

Scalloped Hammerhead Shark 5-Year Review

In 2019, NMFS announced its intent to conduct a 5-year review for the four distinct population segments (DPSs) of the scalloped hammerhead shark (Sphyrna lewini): Eastern Atlantic DPS, Eastern Pacific DPS, Central & Southwest Atlantic DPS, and Indo…
Notice
,
Pacific Islands
Southeast
West Coast
Foreign
Published

Listing of the Scalloped Hammerhead Shark Under the ESA

In response to a petition submitted by WildEarth Guardians and Friends of Animals, we, NOAA Fisheries, are issuing a final determination to list the Central and Southwest (SW) Atlantic Distinct Population Segment (DPS) and the Indo-West Pacific DPS of…
Final Rule
Effective

Determination on the Designation of Critical Habitat for Scalloped Hammerhead Shark

We, NOAA Fisheries, find that there are no marine areas within the jurisdiction of the United States that meet the definition of critical habitat for the Central and Southwest (Central & SW) Atlantic Distinction Population Segment (DPS), Indo-West…
Notice
Published

Science Overview

Documents

Document

Scalloped Hammerhead Shark 5-Year Review

A 5-year review is a periodic analysis of a species’ status conducted to ensure that the listing…

Pacific Islands
Southeast
West Coast
International
Document

Status Review Report for Scalloped Hammerhead Shark (Sphyrna lewini)

The March 2014 status review report conducted in response to a petition to list the scalloped…

Pacific Islands
Southeast
West Coast
International
More Documents