Spinner Dolphin
Spinner Dolphin
Stenella longirostris
![Side-profile illustration of a spinner dolphin with a dark gray dorsal fin, light gray side, and white belly.](/s3//styles/original/s3/dam-migration/640x427-spinner-dolphin.png?itok=vN0dNT-x)
Protection Status
Quick Facts
![PIFSC_20100927-S87_ACU-09139](/s3//styles/full_width/s3/dam-migration/750x500-spinner-dolphin08-nmfs-permit-14097.jpg?itok=xZfkO4Vx)
Spinner dolphin. Credit: Adam U (NOAA Fisheries Permit #14097)
About the Species
![PIFSC_20100927-S87_ACU-09139](/s3//styles/full_width/s3/dam-migration/750x500-spinner-dolphin08-nmfs-permit-14097.jpg?itok=xZfkO4Vx)
Spinner dolphin. Credit: Adam U (NOAA Fisheries Permit #14097)
Spinner dolphins are probably the most frequently encountered cetacean in nearshore waters of the Pacific Islands Region. Spinner dolphins received their common name because they are often seen leaping and spinning out of the water. The species' name, longirostris, is Latin for “long beak,” referring to their slender shaped beak or rostrum.
Regarded as one of the most acrobatic of dolphins, spinner dolphins are well known for their habit of leaping from the water and spinning up to seven times in the air before falling back into the water. Experts believe that spinner dolphins use these behaviors primarily for acoustic signaling or communication, but the activity can also be a way to remove ectoparasites, such as remoras.
Appearance
Spinner dolphins are relatively small compared with other species of oceanic dolphins. They are slender, with thin, recurved flippers, and dorsal fins that usually range from slightly curved to erect and triangular. Among Gray’s spinner dolphins (the subspecies that includes Hawaiian spinner dolphins), adult females are 4.6 to 6.7 feet long and adult males are 5.2 to 6.8 feet long. They reach weights of at least 181 pounds. There is a great deal of color variation in spinner dolphins across the globe, depending on the region and subspecies of dolphin. Gray’s spinner dolphins exhibit a tripartite color pattern with counter shading from dark to light. The three-part color region consists of a dark gray dorsal/back cape, a light gray side, and a white belly.
Individual dolphins are identified by their unique dorsal fins. Researchers take photographs of the dolphins' dorsal fins and then match the shape, nicks, and notches in each fin to a catalog of known individuals to obtain life history information for each animal.
Behavior and Diet
Spinner dolphins feed at night on species including small fish, shrimp, and squid that are found about 650 to 1,000 feet below the surface of the water. Spinner dolphin prey species follow a vertical and horizontal migration pattern, staying in deep waters in the ocean during the day, and then moving up in the water column (vertical migration) and inshore (horizontal migration) at night. Spinner dolphins take advantage of the nightly migration that brings their prey species to shallower depths and closer to shore by feeding throughout the night.
When resting, spinner dolphins move back and forth slowly as a single unit, with the animals in tight formation but spaced just out of contact with one another. They may engage in resting behaviors for about four to five hours daily. This behavior may vary seasonally, coinciding with the shifts in day length. During rest, spinner dolphins rely on vision rather than echolocation for scanning their environment. Group movements during rest are typically in open, sandy-bottom areas where predators are more visible.
At the end of their rest period, spinner dolphins usually abruptly increase their activity level, including their swim speeds, aerial behaviors, vocalizations, and make shorter dives than when resting. In 1994, researchers described spinner dolphins swimming in a “zig-zag” pattern following their rest period. They swam toward the open waters and then doubled back into shallower waters. This back-and-forth swimming repeats a zig-zag formation over most of the area, possibly functioning as a social cue for the entire group to coordinate their movement into the deeper seas. Likewise, the dolphins’ acoustic behaviors rise and fall synchronously with the zig-zag swimming patterns. When these patterns subside, the spinner dolphins swiftly race to the offshore waters of their foraging grounds, where they are sometimes joined by bottlenose or spotted dolphins. At this point, spinner dolphins’ dive times are extended and the dolphins begin their foraging movements.
Where They Live
Habitat
In most places, spinner dolphins are found in areas of deep waters where they likely track prey. Although the pelagic stock of Hawaiian spinner dolphins are found in the deeper waters offshore of the islands, the rest of the Hawaiʻi population has a more coastal distribution. During daytime hours, the island-associated stocks of Hawaiian spinner dolphins seek sanctuary in nearshore waters, where they return to certain areas to socialize, rest, and nurture their young. These areas are typically in clear, calm, and relatively shallow waters. They usually have a sandy bottom that presumably provides an environment in which the dolphins are able to visually monitor for predators, as they cease echolocation while they rest. Spinner dolphins use a variety of bays and nearshore coastal waters throughout their range, but they seem to prefer certain bays.
Distribution
Spinner dolphins are found throughout the world in tropical and warm-temperate waters. Four subspecies of spinner dolphins have been described worldwide:
- Stenella longirostris longirostris (also known as Gray’s spinner dolphin)—which includes the Hawaiian spinner dolphin—in the tropical Atlantic, Indian, and western and central Pacific Oceans.
- S. l. orientalis in the eastern tropical Pacific Ocean
- S. l. centroamericana near Central America
- S. l. rosiventris, the dwarf spinner dolphin, in southeast Asia to northern Australia
The Gray’s spinner dolphin is the typical form of spinner dolphin found in most areas of the world.
Lifespan & Reproduction
Like all marine mammals, spinner dolphins are slow reproducers. They live for about 20 years, with some individuals living for at least 25 years. Spinner dolphins may mate year-round, with multiple males mating with one female. Gestation is similar to other dolphin species and lasts approximately 11 months. Spinner dolphins calve year-round, generally about once every 3 years, and lactate often for 1 to 2 years. They reach sexual maturity at around 7 years of age.
Threats
Human Interactions and Viewing Pressure
Viewing wild marine mammals in Hawaiʻi has been a popular recreational activity for both tourists and residents over the past several decades. We estimate that there are upwards of 70 tour operators that provide dolphin-directed tours focused on Hawaiian spinner dolphins. More than 100 commercial boat tour and kayak tour operations may opportunistically view these animals.
Tours operate out of various harbors along most of the coasts of the main Hawaiian Islands, bringing guests to well-known locations for spinner dolphin viewing. Researchers have observed up to 13 tour boats at a time in some locations, with vessels jockeying for position on a single spinner dolphin group and more than 60 swimmers in the water attempting to closely interact with the dolphins at once. In addition, a number of residents and visitors venture on their own, independent of commercial operators, to view and interact with spinner dolphins. Some operators and various media outlets have encouraged the expectation for close interactions with wild dolphins, and routinely promote close vessel or in-water encounters with the dolphins. This contradicts established wildlife viewing guidelines.
Commercial operators and individuals interested in viewing or closely interacting with Hawaiian spinner dolphins increasingly target the dolphins' essential daytime habitats. Encounters with dolphins in these areas are very common due to the predictability of spinner dolphin behavior. Viewing spinner dolphins in their natural habitat can be an educational and enriching experience if conducted safely and responsibly from a distance. However, closely approaching, swimming with, pursuing, interacting, or attempting to interact with the dolphins could disrupt their daytime behaviors. Some interactions with people in essential daytime habitats may disturb individual dolphins or resting groups, even rising to the level of “take” under the Marine Mammal Protection Act, which is illegal.
Response to disturbance varies among individuals, but ultimately diverts time and energy from fitness-enhancing activities (such as resting and recuperating after an energetically-costly night of foraging for prey). These responses may, over time, result in negative effects to the fitness of individuals or resident populations. For example, lack of consistent, undisturbed resting periods can reduce the amount of energy available for a spinner dolphin to engage effectively in foraging activities at night. Over time, this can result in overall poor body condition, which reduces the dolphin’s ability to fight off disease, protect itself from predators, successfully reproduce, or rear young.
Peer-reviewed scientific literature has documented disturbance responses by individual spinner dolphins, as well as changes to spinner dolphin group behavior patterns over time. Individual dolphin responses include:
- Increased displays such as leaping, spinning, or tail slapping when closely approached by vessels and swimmers.
- Avoidance behaviors, including increased swimming speed and moving away from swimmers and vessels, or leaving the bay completely in response to human pursuit.
- Aggressive behaviors directed at people, including charging or threat displays.
Researchers have also documented changes to spinner dolphins’ behavior patterns in essential daytime habitats, including changes to patterns associated with aerial behaviors, residence times, and distribution within the habitat. Human-caused disturbances to daily behaviors may be incidents of 'take,' as defined (and prohibited) under the Marine Mammal Protection Act. The chronic nature of these problems in Hawaiʻi and the observed changes to behavioral patterns over time are a cause for concern for this dolphin population.
Marine Debris
Marine debris is a growing concern within the marine environment, as it poses multiple threats to the marine ecosystem. For instance, spinner dolphins may ingest (either directly or through prey items) or become entangled in marine debris. These interactions may cause:
- Drowning
- Debilitation
- Limited predator avoidance
- Internal or external wounds
- Skin lesions or sores
- Blockage of the digestive tract, resulting in starvation that often leads to death
- Reductions in quality of life and/or reproductive capacity
- Impairment of feeding capacity
- Introduction and/or concentration of damaging or toxic compounds to the animal
The severity of the effects of debris interactions on all dolphin populations remains unclear because many deaths likely occur undetected at sea
We do not have sufficient information to determine the severity of the threat of direct ingestion of large debris on spinner dolphin populations. Some data indicates that spinner dolphin prey species are consuming very small plastics. In 2010, researchers analyzed mesopelagic fish in the North Pacific Central Gyre and found that 35 percent of the fish—many of which were lantern fish (spinner dolphins’ main prey)—had ingested plastic. Larger fish generally had more pieces of plastic in their guts than smaller fish. We are particularly concerned about the ability for plastic debris to absorb organic pollutants that may be toxic to the marine organisms that ingest them. These contaminants can bioaccumulate as they move up the food chain to top predators such as spinner dolphins. Scientists have also found high levels of butyltin and organochlorine (chemical compounds found in some plastics) in migrating lantern fish species in the Western North Pacific, which may indicate a cause for concern for predators, such as spinner dolphins.
Human-Made Noise
Humans introduce sound intentionally and unintentionally into the marine environment. This could be from commercial and recreational ocean activities, navigation, oil and gas exploration and acquisition, research, and military activities. Spinner dolphins use sound to communicate, navigate, locate prey, locate predators, and sense their environment, which can be impacted by introduced anthropogenic noise How severely noise exposure affects dolphins and whales depends on factors including:
- Noise source
- Decibel level
- Distance between the source and the animal
- Characteristics of the animal (for example, hearing sensitivity, behavioral context, age, sex, and previous experience with sound source)
- Time of day or season (which affects how sound travels through the water)
In marine mammal populations, noise can seriously disrupt communication, navigational ability, and social patterns.
Disease
Spinner dolphins, like all marine mammals, can be susceptible to widespread disease. Outbreaks in spinner dolphins are not commonly reported, but scientists have previously detected serious diseases, such as toxoplasmosis and cetacean morbillivirus. Although the number of spinner dolphin deaths attributed to these diseases is fairly low (many are thought to be unreported), thousands of other marine mammal species have died from these diseases worldwide.
Scientific Classification
Kingdom | Animalia | Phylum | Chordata | Class | Mammalia | Order | Cetacea | Family | Delphinidae | Genus | Stenella | Species | longirostris |
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Last updated by NOAA Fisheries on 04/15/2024
What We Do
Conservation & Management
We are committed to protecting spinner dolphins through various conservation, regulatory, and enforcement measures. Our work includes:
- Proposing enhanced protections of Hawaiian spinner dolphins through regulatory action under the Marine Mammal Protection Act
- Promoting sustainable and legal wildlife viewing practices among the tourism industry and local communities
- Developing research priorities to monitor spinner dolphin abundance, health, and threats (such as human disturbance)
- Managing programs that support the protection and conservation of spinner dolphins, including Dolphin SMART, the Dolphin-Safe Program, and the Dolphin Energetics Program
- Educating the public on minimizing spinner dolphin disturbance by providing outreach programs and educational materials
Science
We conduct various research activities on the biology, behavior, and ecology of the spinner dolphin. The results of this research inform management decisions and enhance recovery efforts for this species. Our work includes:
- Research such as photo-identification studies
- Cetaceans surveys
- Acoustics monitoring
How You Can Help
![Wildlife Viewing](/themes/custom/noaa/images/icons/wildlife-viewing%402x.jpg)
Do Not Interact with Marine Animals in the Wild
Do not harass, feed, hunt, capture, kill, pursue, approach, surround, swim with, or attempt to touch protected marine wildlife. Never entice protected marine wildlife to approach you.
Do not engage, chase, or try to get a reaction from the animal. Disturbing wildlife interrupts their ability to perform critical functions such as feeding, breeding, nursing, resting, and socializing.
Learn more about viewing marine wildlife in Hawai‘i
If you’re on a vessel and a marine animal approaches you, put the engine in neutral and allow the animal to continue on its way. If a spinner dolphin approaches your vessel, continue normal navigation and make no effort to engage or pursue the animal.
It is prohibited to swim-with and approach or remain within 50 yards of a Hawaiian spinner dolphin (for persons, vessels, and objects), including approach by interception (i.e., “leapfrogging”).
Learn more about the protections for Hawaiian spinner dolphins against disturbance
![Marine Life In Distress](/themes/custom/noaa/images/icons/marine-life-in-distress%402x.jpg)
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](/themes/custom/noaa/images/icons/report%402x.jpg)
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 office during regular business hours.
![Keep your distance](/themes/custom/noaa/images/icons/wildlife-viewing%402x.jpg)
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.
Featured News
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Population Highlights
![Spinner dolphin in mid-air](/s3//styles/media_750_x500/s3/dam-migration-miss/1280_M4bOz8PM5u42_0.jpg?itok=n5HYi6fq)
The Hawaiian population of spinner dolphins spend their daylight hours in coastal waters, generally in calm bays. They use these areas to rest, socialize, care for their young, and avoid predators. At night, they travel to deeper water to hunt for food. Spinner dolphins have what is called a "fission-fusion social pattern." They "fuse" to form large schools of hundreds of animals when feeding at night and split off into much smaller groups—sometimes of only a dozen individuals—when socializing and resting during the day.
Protected Status
A robust estimate for the population size of spinner dolphins is only available for the Hawaiʻi Island stock, which is estimated to be around 600 animals. The Kauaʻi/Niʻihau stock is estimated to be around 600 animals and Oʻahu/4-Islands stock is estimated to be around 300 animals. Both of these estimates lack data from the stocks' full ranges. Information is insufficient to provide estimates for the other three stocks.
Distribution
Spinner dolphins occur throughout the entire Hawaiian Archipelago. Because of genetic differences between spinner dolphins throughout the islands and atolls, the population in Hawaiʻi has five distinct island-associated stocks. The stocks are as follows: 1) Midway/Kure, 2) Pearl and Hermes Reef, 3) Kauaʻi and Niʻihau, 4) Oʻahu/4-Islands (including Maui, Lānaʻi, Molokaʻi, and Kahoʻolawe), and 5) Hawaiʻi Island. These stocks live in coastal waters to 10 nautical miles from the shore of their resident island(s). All other spinner dolphins found outside of 10 nautical miles and within the U.S. Exclusive Economic Zone (including those at French Frigate Shoals) are part of the Pelagic stock. The genetic data suggest that these stocks are reproductively isolated populations, meaning that there is little to no breeding between stocks.
Last updated by NOAA Fisheries on 04/15/2024
Management Overview
Spinner dolphins, like all marine mammals, are protected under the Marine Mammal Protection Act (MMPA). NOAA Fisheries is dedicated to conserving spinner dolphin populations through numerous management and regulatory actions.
Legal Protection
All marine mammals are protected from "take" under the MMPA. The MMPA defines take to mean: "to harass, hunt, capture, or kill" any marine mammal or attempt to do so. Harassment is further defined as any act of pursuit, torment, or annoyance which has the potential to do the following:
- Level A harassment—injure a marine mammal or marine mammal stock in the wild.
- Level B harassment—disturb a marine mammal or marine stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering.
When viewing spinner dolphins in the wild, people must ensure their activities will not result in "take." Activities that result in take can include close approach to dolphins, by vessel or any other means, including activities like swimming with the dolphins. It is prohibited to swim-with and approach or remain within 50 yards of a Hawaiian spinner dolphin (for persons, vessels, and objects), including approach by interception (i.e., “leapfrogging”).
Current Management Issues
Resident populations of Hawaiian spinner dolphins feed offshore throughout the night and return to the coasts of Hawaiʻi to rest during the day. Hawaiian spinner dolphins rest in the sheltered bays of Hawaiʻi and along its coastlines, which overlaps with areas that humans use to recreate. They are one of the most easily encountered cetaceans in the waters of the main Hawaiian Islands, and thus they are vulnerable to disturbance and harassment. Dolphin-directed activities have grown dramatically in recent years, and the easily accessible Hawaiian spinner dolphins face heavy and increasing pressure from people seeking a dolphin experience. These chronic disturbances to resting dolphins can negatively affect their health, fitness, and ultimately their survival.
NOAA Fisheries’ Pacific Islands Regional Office published a final rule prohibiting swimming with, approaching, or remaining within 50 yards of a Hawaiian spinner dolphin on September 28,2021. A proposed rule to establish mandatory time-area closures of Hawaiian spinner dolphins' essential daytime habitats was also published on September 28, 2021.
Conservation Efforts
Promoting Responsible Wildlife Viewing
It is prohibited to swim-with and approach or remain within 50 yards of a Hawaiian spinner dolphin (for persons, vessels, and objects), including approach by interception (i.e., “leapfrogging”) within 2 nautical miles from shore of the main Hawaiian Islands and in designated waters bounded by the islands of Lāna‘i, Maui, and Kahoʻolawe.
Learn more about the Hawaiian spinner dolphin swim-with and approach regulation
- Six reasons why you should not swim with wild spinner dolphins
- Marine Life Viewing Guidelines
- Viewing Marine Wildlife in Hawaiʻi
- Be Dolphin SMART
NOAA Fisheries has developed wildlife viewing guidelines for spinner dolphins and other protected species to help the public understand how to responsibly and legally view these animals. To be compliant with the law, it is best to follow the guidelines.
Overseeing Marine Mammal Health and Stranding Response
We work with volunteer networks in all coastal states to respond to marine mammal strandings including all dolphins and porpoises. When stranded animals are found alive, NOAA Fisheries and our partners assess the animal’s health and determine the best course of action. 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 attribute strandings to disease, harmful algal blooms, vessel strikes, fishing gear entanglements, pollution exposure, and underwater 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
Marine Mammal Unusual Mortality Events
Spinner dolphins have been part of a declared unusual mortality event in the past. Under the Marine Mammal Protection Act, an unusual mortality event 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
Dolphin-Safe/Tuna Tracking and Verification Program
Dolphins, like other marine mammals, may become bycatch in fisheries. Some species of tuna are known to aggregate beneath schools of certain dolphin stocks. In some parts of the world, this close association led to the fishing practice of encircling a dolphin school to capture the tuna concentrated below, to the detriment of the dolphins, which would get trapped in the net. The Dolphin Protection Consumer Information Act established a national tuna tracking program to ensure that tuna imported into the United States meets certain requirements to ensure the safety of dolphins during tuna fishing operations.
Learn more about the Dolphin-Safe/Tuna Tracking and Verification Program
Dolphin SMART
Dolphin SMART is a partnership program that was developed by NOAA Fisheries, NOAA Office of Marine Sanctuaries, the Whale and Dolphin Conservation, and the Dolphin Ecology Project. The goal of the program is to promote responsible stewardship of wild dolphins. The acronym SMART stands for:
S = Stay back 50 yards from dolphins
M = Move away cautiously if dolphins show signs of disturbance
A = Always put your engine in neutral when dolphins are near
R = Refrain from feeding, touching, or swimming with wild dolphins
T = Teach others to be Dolphin SMART
Regulatory History
In 2005, NOAA Fisheries convened a Spinner Dolphin Working Group to enhance protections for Hawaiian spinner dolphins from human disturbance. This group consisted of individuals from the Marine Mammal Commission and state and federal agencies that participate in spinner dolphin research and conservation. We used deliberations from this working group to inform an Advance Notice of Proposed Rulemaking that was published in the Federal Register in December 2005. A Notice of Intent (NOI) to Prepare an Environmental Impact Statement followed, in which we identified five preliminary alternatives for consideration and comment:
- Partial (time-area based) closures for certain spinner dolphin resting habitats
- A No Action Alternative
- Establishing a minimum distance limit
- Regulation of human behavior while in NOAA Fisheries-identified spinner dolphin resting areas
- Complete closure of all known spinner dolphin resting areas in the main Hawaiian Islands
This notice invited information from the public on the scope of the issues that should be addressed in the Draft Environmental Impact Statement (DEIS), the issues of concern regarding practical considerations involved in applying the proposed regulations, and the identification of environmental and socioeconomic concerns to be addressed in the analysis. The notice also sought to determine whether NOAA Fisheries addressed the appropriate range of alternatives.
On August 23, 2016, NOAA Fisheries published the DEIS and a proposed rule to enhance protections for Hawaiian spinner dolphins to prevent disturbance and harassment from dolphin-directed human activities. The proposed rule would prohibit swimming with and approaching a Hawaiian spinner dolphin within 50 yards by any means (vessel, person, or other object) and would be implemented within two nautical miles from shore of the main Hawaiian Islands and in designated waters between Maui, Lānaʻi, and Kahoʻolawe where spinner dolphins are found throughout the day. On July 30, 2021, NOAA Fisheries published a Notice of Availability for the Final Environmental Impact Statement (FEIS). A Record of Decision was signed on September 28, 2021 and a final rule prohibiting swimming with, approaching, or remaining within 50 yards of a Hawaiian spinner dolphin was published on September 28, 2021. NOAA Fisheries also published a proposed rule to establish time-area closures at Hawaiian spinner dolphin’s essential daytime habitats on September 28, 2021.
Key Actions and Documents
More Information
Last updated by NOAA Fisheries on 04/15/2024
Science Overview
NOAA Fisheries conducts various research activities to learn about the biology, behavior, and ecology of spinner dolphins. This research informs management decisions and enhances recovery efforts for spinner dolphin populations.
Population Assessments
Determining the size of spinner 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.
Photo-Identification Studies
Long-term photo-identification (photo-ID) studies provide insight into habitat use, movements, and life history characteristics of individual spinner dolphins. Some species of cetaceans have unique, naturally occurring markings on their bodies or dorsal fins. We use photographic records of these scars, nicks, notches, or color patterns to identify individuals. We also archive our photographs of spinner dolphins with other sighting data, such as location, group size and structure, and behavior. We can then track individual cetaceans over time and between locations on the basis of these photo-IDs.
Our cetacean scientists conduct photo-ID research throughout the Hawaiian Islands, at Palmyra Atoll, and around Guam and the Commonwealth of the Northern Mariana Islands. These long-term studies will help establish new stock boundaries for island-associated cetaceans in each region. Once we establish the photo catalogs, we can also use them to evaluate species abundance using mark-recapture techniques.
Photo-Identification Network
Our cetacean scientists are active participants in the Pacific Islands Photo-Identification Network (PIPIN). This group of researchers from the Hawaiian Islands studies spinner dolphins and uses photo-ID as a primary research tool. PIPIN is creating a collaborative photo-ID database of spinner dolphin populations within the Hawaiian Islands. This will help us study movements of dolphins between islands (if they occur), and to determine if dolphin populations differ from one island to the next. Results of the cooperative studies will help managers assess and resolve issues with human-dolphin interactions, such as effects on spinner dolphins arising from "swim-with-dolphins" tourism operations.
Hawaiian Islands Cetacean and Ecosystem Assessment Survey
The Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS, pronounced "high-seas") is a large-scale ship survey for whales, dolphins, and seabirds within the U.S. waters of the Hawaiian Islands. The study area is approximately 1.8 million square nautical miles, which includes waters surrounding all Northwestern and main Hawaiian Islands out to 200 nautical miles offshore. Waters within this 200 nautical miles boundary around the Hawaiian Islands are referred to as the U.S. Exclusive Economic Zone.
HICEAS is a collaboration between the Pacific Islands Fisheries Science Center located in Honolulu, Hawai`i, and the Southwest Fisheries Science Center located in La Jolla, California. NOAA Fisheries has conducted HICEAS in 2002, 2010, and 2017. The goals are to estimate how many whales and dolphins are in Hawaiian waters, examine their population structure, and understand their habitat.
There are four major research components to HICEAS:
- Visual observations for cetaceans, including photo-ID, biopsy sampling, and satellite tagging
- Passive acoustic monitoring using towed hydrophone arrays and other tools
- Ecosystem assessment, including visual surveys for seabirds and measurement of oceanographic variables
In the winter of 2020, another research cruise, the Winter Hawaiian Islands Cetacean and Ecosystem Assessment Survey (WHICEAS; pronounced “why-seas”) was conducted to focus on baleen whales that may migrate to the area during this time and to examine changes in density of other species between winter and summer. Like HICEAS, this project also used traditional cetacean survey methods such as visual observations and acoustic detections.
Other ancillary projects, such as aerial photogrammetry using a hexacopter, testing of new passive acoustic tools, and projects that support and augment our assessment mission.
Last updated by NOAA Fisheries on 04/15/2024
Documents
Fact Sheet: Proposed Time-Area Closures for Hawaiian Spinner Dolphins
Fact sheet on NOAA’s proposed rule to establish time-area closures to protect Hawaiian spinner…
Final Environmental Impact Statement for Enhancing Protections for Hawaiian Spinner Dolphins to Prevent Disturbance
Analysis of a proposed action and alternatives to enhance protections for Hawaiian spinner dolphins…
Assessing Cetacean Populations in the Mariana Archipelago: A Summary of Data and Analyses from 2010-2019
This report summarizes the surveys, data collection, and analyses conducted by PIFSC for cetaceans…
Injury Determinations for Humpback Whales and Other Cetaceans Reported to NOAA Response Networks in the Hawaiian Islands During 2018
During 2018, there were 19 reports of cetaceans with human-caused injuries, including 4 humpback…
Research
Population Consequences of the Deepwater Horizon Oil Spill on Pelagic Cetaceans
We quantified population consequences for pelagic cetaceans, including sperm whales, beaked whales,…
Question of the Week: Dolphins and Whales on the High Seas
Question: Why are large scale surveys like HICEAS so rare when they seem to be quite important and interesting? — Jessica (Honolulu, HI) Answer: HICEAS 2017 was the first survey of its kind in Hawaii since 2010. These surveys are rare because our…
Pacific Islands Volunteer Opportunities
Want to help protect our marine resources? If you’re able to contribute your time and energy with a positive, “can-do” attitude, here are some opportunities to join in and help out!
Outreach & Education
Valentine Cards to “Share the Love” for Marine Animals in the Pacific Islands Region
Eight valentine cards with drawings to color, fun facts, and viewing distances for humpback whales,…
A Day in the Life of a Wild Spinner Dolphin Poster
An educational poster illustrating the daytime resting and nighttime feeding activities of a…
Last updated by NOAA Fisheries on 04/15/2024