Fraser's Dolphin
Lagenodelphis hosei

Protected Status
Quick Facts

About The Species
Fraser's dolphins are found in deep, tropical waters worldwide. They are active swimmers and are usually found in groups of 10 to 100 individuals, but they sometimes travel in groups of up to 1,000.
Francis Fraser, a scientist from the British Museum, first described this species in 1956 based on a skull found on a beach in Borneo. It was not until 1971, however, that scientists first documented Fraser’s dolphins in the wild.
Fraser’s dolphins, like all marine mammals, are protected under the Marine Mammal Protection Act. NOAA Fisheries and its partners are working to conserve Fraser’s dolphins and further our understanding of this species through research and conservation activities.
Status
NOAA Fisheries estimates population size in its stock assessment reports.
While the worldwide population of Fraser's dolphins is unknown, scientists estimate that at least 100,000 to 289,000 Fraser’s dolphins live in the eastern tropical Pacific Ocean.
To manage Fraser's dolphins in U.S. waters, we have divided them into three stocks: the Hawaiian stock, the northern Gulf of Mexico stock, and the western North Atlantic stock. Our scientists estimate that there are about 10,000 dolphins in the Hawaiian stock; the number of dolphins in the Gulf of Mexico and western North Atlantic stocks is unknown.
Protected Status
CITES Appendix II
- Throughout Its Range
MMPA Protected
- Throughout Its Range
Appearance
Fraser’s dolphins have a stocky body with a small, distinct beak. Their dorsal fin—located midway down their back—is small and triangle-shaped. Their flippers and flukes are smaller than those of other dolphin species. Males are slightly longer and heavier than females. They also have more distinct color patterns.
All Fraser's dolphins have a dark stripe that extends down their side from eye to flipper. This stripe reminds some people of a raccoon or "bandit" mask. The exact shape of the stripe varies based on geography and sex. Their upper body is a bluish or brownish-gray, while their underside is usually pale white or pink. Calves are usually less colorful than adults.
Behavior and Diet
Fraser's dolphins are usually found in large, tight groups of 10 to 100 individuals, but they have sometimes been seen in groups of up to 1,000 individuals. They are also sometimes seen in mixed groups with related species such as false killer whales, melon-headed whales, Risso's dolphins, and short-finned pilot whales.
Fraser’s dolphins are aggressive and splashy swimmers creating a distinctive spray of water. Groups of individuals sometimes swim in long "chorus line” formations. Fraser's dolphins in some parts of the world are shy and hard to find, while those living in other area are friendly and curious when interacting with vessels.
Fraser's dolphins can dive up to 2,000 feet to feed on deep-sea fish, crustaceans (such as shrimp), and cephalopods (such as squid and octopus). They have 20 to 44 pairs of small, cone-shaped teeth to help them catch rey.
Where They Live
Fraser's dolphins are found in warm, temperate, subtropical, and tropical waters around the world. They prefer to live in deep waters (3,300 feet deep) and are often found in areas of upwelling (areas where cold, nutrient-rich water rises toward the surface). They also live near coastlines or where the continental shelf (the edge of a continent below the ocean’s surface) is narrow.
Stranded Fraser's dolphins have sometimes been reported in places outside of their typical range, such as southern Australia, France, western Scotland, and Uruguay.
Lifespan & Reproduction
Fraser’s dolphins live about 18 years and become sexually mature when they are 5 to 10 years old (females at 5 to 8 years, males at 7 to 10 years). Females are pregnant for about 10 to 12.5 months and give birth to a single calf every 2 years, usually between spring and autumn.
Threats
Interactions with Fishing Gear
One of the main threats to Fraser’s dolphins is getting caught in fishing gear. Dolphins can become entangled or captured in commercial fishing gear such as gillnets, seines, trawls, trap pots, and longlines. Specifically, they have been caught in tuna purse seine fisheries in the eastern tropical Pacific and the Philippines. These interactions can injure dolphins or kill them by entanglement in the gear.
Hunting
Fisheries in Indonesia, Japan, the Lesser Antilles, the Philippines, and Sri Lanka hunt and kill Fraser’s dolphins for meat and oil.
Scientific Classification
Kingdom | Animalia | Phylum | Chordata | Class | Mammalia | Order | Cetacea | Family | Delphinidae | Genus | Lagenodelphis | Species | hosei |
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What We Do
Conservation & Management
NOAA Fisheries is committed to the protection of Fraser’s dolphins. Targeted management actions taken to secure protections for these whales include:
- Overseeing marine mammal health and stranding response.
- Addressing ocean noise.
- Educating the public about Fraser’s dolphins and the threats they face.
Science
Our research projects have discovered new aspects of Fraser’s dolphin biology, behavior, and ecology and help us better understand the challenges that all Fraser’s dolphins face. Our work includes:
- Stock assessments.
- Monitoring population abundance and distribution.
How You Can Help

Keep Your Distance
Be responsible when viewing marine life in the wild.
Observe all dolphins and porpoises from a safe distance of at least 50 yards and limit your time spent observing to 30 minutes or less.

Report Marine Life in Distress
Report a sick, injured, entangled, stranded, or dead animal to make sure professional responders and scientists know about it and can take appropriate action. Numerous organizations around the country are trained and ready to respond. Never approach or try to save an injured or entangled animal yourself—it can be dangerous to both the animal and you.
Learn who you should contact when you encounter a stranded or injured marine animal >

Report a Violation
Call the NOAA Fisheries Enforcement Hotline at (800) 853-1964 to report a federal marine resource violation. This hotline is available 24 hours a day, 7 days a week for anyone in the United States.
You may also contact your closest NOAA Office of Law Enforcement field during regular business hours.
In the Spotlight
Management Overview
Fraser’s dolphins, like all marine mammals, are protected under the Marine Mammal Protection Act. In the United States, NOAA Fisheries works to protect all stocks of Fraser’s dolphins.
Fraser's dolphins swimming in the eastern tropical Pacific Ocean. Photo: NOAA Southwest Fisheries Science Center/Anne Douglass.
Conservation Efforts
Overseeing Marine Mammal Health and Stranding Response
We work with volunteer networks in all coastal states to respond to marine mammal strandings, including dolphins. When stranded animals are found alive, NOAA Fisheries and our partners assess the animal’s health. When stranded animals are found dead, our scientists work to understand and investigate the cause of death. Although the cause often remains unknown, scientists can sometimes identify strandings due to disease, harmful algal blooms, vessel strikes, fishing gear entanglements, pollution exposure, and ocean noise. Some strandings can serve as indicators of ocean health, giving insight into larger environmental issues that may also have implications for human health and welfare.
Learn more about the Marine Mammal Health and Stranding Response Program
Addressing Ocean Noise
Underwater noise threatens dolphin populations, interrupting their normal behavior and driving them away from areas important to their survival. Increasing evidence suggests that exposure to intense underwater sound in some settings may cause some dolphins to strand and ultimately die. NOAA Fisheries is investigating all aspects of acoustic communication and hearing in marine animals, as well as the effects of sound on whale behavior and hearing. In 2016, we issued technical guidance for assessing the effects of anthropogenic (human-caused) sound on marine mammals’ hearing.
Marine Mammal Unusual Mortality Events
Under the Marine Mammal Protection Act, an unusual mortality event (UME) is defined as "a stranding that is unexpected; involves a significant die-off of any marine mammal population; and demands immediate response." To understand the health of marine mammal populations, scientists study unusual mortality events.
Get information on active and past UMEs
Get an overview of marine mammal UMEs
Educating the Public
NOAA Fisheries aims to increase public awareness and support for Fraser’s dolphin conservation through education, outreach, and public participation. We share information with the public about the status of Fraser’s dolphins, as well as our research and efforts to promote their recovery.
Regulatory History
Fraser’s dolphins, like all marine mammals, are protected in the United States under the MMPA.
Key Actions and Documents
Incidental Take Authorization: Scripps Institute of Oceanography Low-Energy Geophysical Survey in the South Atlantic Ocean
Incidental Take Authorization: Low-Energy Geophysical Survey in the Southwest Atlantic Ocean
Incidental Take Authorization: U.S. Navy Mariana Islands Training and Testing (MITT)
- Letter of Authorization (pdf, 33 pages)
- Revised LOA Application (pdf, 325 pages)
- LOA Application (pdf, 318 pages)
- Monitoring and Reporting
- Notification and Reporting Plan (pdf, 4 pages)
- Biological Opinion
- Environmental Impact Statement
- Public Comments
- NRDC Comment Letter (pdf, 37 pages)
- References (pdf, 25 pages)
Incidental Take Authorization: U.S. Navy Hawaii-Southern California Training and Testing (HSTT) (2018-2025)
- Final Rule for 2 Year Extension
- Proposed Rule for 2 Year Extension
- Notice of Receipt of Application for 2 Year Extension
- Final Rule
- Proposed Rule
- Notice of Receipt of Application for LOA
- LOA for Testing (pdf, 38 pages)
- LOA for Training (pdf, 38 pages)
- Application for Extension (pdf, 84 pages)
- LOA and Rule Application (pdf, 580 pages)
- Monitoring Reports (External Link)
- Environmental Impact Statement (External Link)
- Mitigation Addendum (pdf, 12 pages)
- Notification and Reporting Plan (pdf, 4 pages)
- Final Biological Opinion (pdf, 683 pages)
- Public Comments (External Link)
- References (pdf, 15 pages)
Science Overview
NOAA Fisheries conducts various research activities on the biology, behavior, and ecology of Fraser’s dolphins. The results of this research are used to inform management decisions for this species.

Fraser's dolphins observed during the 2017 Hawaiian Islands Cetacean and Ecosystem Assessment Survey. Photo: NOAA Pacific Islands Fisheries Science Center/Bernardo Alps.
Stock Assessments
Determining the size of Fraser’s dolphin populations helps resource managers determine the success of conservation measures. Our scientists collect population information and present the data in annual stock assessment reports.
Monitoring Population Abundance and Distribution
Scientists observe Fraser’s dolphins to record their numbers and distribution. By comparing numbers collected over multiple years, scientists can look for trends—i.e., whether the population is increasing, decreasing, or remaining stable during a given period.