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The Hawaiian monk seal is one of the most endangered seal species in the world. The population overall has been declining for over six decades and current numbers are only about one-third of historic population levels. Importantly, however, the prol
Hawaiian Monk Seal
Neomonachus schauinslandi
Protected Status
ESA Endangered
Throughout Its Range
MMPA Protected
Throughout Its Range
MMPA Depleted
Throughout Its Range
CITES Appendix I
Throughout Its Range
Quick Facts
Weight
400 to 600 pounds
Length
6 to 7 feet
Lifespan
Maximum age over 30 years
Threats
Food limitation,
Shark predation,
Entanglement,
Male aggression,
Habitat loss,
Disease,
Human impacts (e.g., fishery interactions, disturbance, intentional killing)
Region
Pacific Islands
Young Hawaiian monk seal underwater in Pearl and Hermes Reef in Hawaii. Credit: NOAA Fisheries Hawaiian monk seal research program.
Young Hawaiian monk seal underwater in Pearl and Hermes Reef in Hawaii. Credit: NOAA Fisheries Hawaiian monk seal research program.
About the Species
Young Hawaiian monk seal underwater in Pearl and Hermes Reef in Hawaii. Credit: NOAA Fisheries Hawaiian monk seal research program.
Young Hawaiian monk seal underwater in Pearl and Hermes Reef in Hawaii. Credit: NOAA Fisheries Hawaiian monk seal research program.
The Hawaiian monk seal is one of the most endangered seal species in the world. The population overall had been declining for six decades and current numbers, though increasing, are only about one-third of historic population levels. Importantly, however, the current upward trend is in part due to NOAA Fisheries recovery efforts.
Hawaiian monk seals are found in the Hawaiian archipelago which includes both the main and Northwestern Hawaiian Islands and rarely at Johnston Atoll which lies nearly 1,000 miles southwest of Hawai'i. These monk seals are endemic to these islands, occurring nowhere else in the world. Hawaiian monk seals are protected under the Endangered Species Act, the Marine Mammal Protection Act, and State of Hawai'i law.
The population is estimated to be around 1,600 seals—nearly 1,200 seals in the Northwestern Hawaiian Islands and 400 seals in the main Hawaiian Islands.
A prolonged decline of the Hawaiian monk seal population in the Northwestern Hawaiian Islands occurred after the late 1950s, lasting until very recently. While individual subpopulations increased or decreased during that time, the total number of seals in the Northwestern Hawaiian Islands declined. Although this decline means that a full recovery of the species is a long way off, there are relatively recent, encouraging developments, including:
Visible recolonization and significant growth of the main Hawaiian Islands monk seal subpopulation from low numbers to approximately 400 over the past 2 decades or more
Overall species population growth of 2 percent each year between 2013 to 2022—2021, marked the first time their population exceeded 1,570 in more than 2 decades
Promising advances in juvenile seal survival enhancement research, such as evaluating how translocation affects survival and continued efforts to improve medical treatments
The decline that occurred in the Northwestern Hawaiian Islands was attributed to a number of factors at various regions and time periods. However, low juvenile survival, likely related to limited food availability, was the primary driver of the decline during the past 25 years.
Appearance
Newborn monk seal pups are born black, while weaned pups and older seals are dark gray to brown on their back and light gray to yellowish brown on their belly.
Monk seals undergo a "catastrophic molt" about once per year, where they shed the top layer of their skin and fur (similar to elephant seals). Seals that spend a long time at sea foraging can grow algae on their fur. Those that look green haven't molted recently and may be getting ready to shed into a new silvery coat.
Most Hawaiian monk seals have unique natural markings, such as scars or natural bleach marks (white spots), on their fur which help identify them. Personnel authorized by NOAA Fisheries often apply identification tags to their rear flippers. Tagging and tracking used in combination with identification of unique markings enable long-term monitoring of individuals.
Male and female monk seals are similar in size. The only way to confirm whether a seal is female or male is by looking at its belly.
Behavior and Diet
Hawaiian monk seals are "generalist" feeders, which means they eat a wide variety of foods depending on what's available. They eat many types of common fishes, squids, octopuses, eels, and crustaceans (crabs, shrimps, and lobsters). Diet studies indicate that they forage at or near the seafloor and prefer prey that hide in the sand or under rocks. They do not target most of the locally popular gamefish species such as ulua (giant trevally), pāpio (baby ulua), and ‘ō‘io (bonefish).
Hawaiian monk seals can hold their breath for up to 20 minutes and dive more than 1,800 feet; however, they usually dive an average of 6 minutes to depths of less than 200 feet to forage at the seafloor.
Hawaiian monk seals are mostly solitary and don't live in colonies like sea lions or other seals. But they do sometimes lie near each other—usually not close enough to make physical contact—in small groups. They usually sleep on beaches, sometimes for days at a time. They also occasionally sleep in small underwater caves.
Monk seals do not migrate seasonally, but some seals have traveled hundreds of miles in the open ocean. Individual seals often frequent the same beaches over and over, but they do not defend territories.
Where They Live
Hawaiian monk seals are found throughout the entire Hawaiian archipelago, a distance of 1,500 miles from Kure Atoll (Hōlanikū) in the northwest to Hawaiʻi Island in the southeast. The majority of Hawaiian monk seals (about 1,200 individuals) live in the Northwestern Hawaiian Islands, and a much smaller number (about 400) live in the main Hawaiian Islands. There have also been rare sightings of Hawaiian monk seals, as well as a single birth, at Johnston Atoll, the closest atoll southwest of the Hawaiian Islands.
Monk seals live in warm, subtropical waters and spend two-thirds of their time at sea. They use the waters surrounding atolls and islands and areas farther offshore on reefs and submerged banks; they also use deepwater coral beds as foraging habitat. When on land, monk seals haul-out to rest, molt, give birth and nurse on sand, coral rubble, and volcanic rock shorelines. They generally prefer sandy, protected beaches surrounded by shallow waters for pupping.
World map providing approximate representation of the Hawaiian monk seal range
Lifespan & Reproduction
Monk seals can live to over 30 years of age, but few live that long. Monk seals mate in the water. The youngest documented female to give birth was 4 years old, but typically females begin reproducing at age 5 to 6 in the main Hawaiian Islands and age 7 to 10 in the Northwestern Hawaiian Islands.
Limited food intake by juvenile seals was a major factor driving the population decline in the Northwestern Hawaiian Islands for many years. However, improved survival of young seals in recent years seems to be driving the positive abundance trends. In the Northwestern Hawaiian Islands, seals must compete for food with large populations of other apex predators, such as large jacks (carangids) and sharks. Shifts in ecosystem productivity, caused by global climate change and/or cyclical changes, may also contribute to food limitation.
Shark Predation
Since the late 1990s, predation by Galapagos sharks on pre-weaned and recently weaned seal pups has been a chronic and significant cause of injury and mortality specific to French Frigate Shoals (Lalo) in the Northwestern Hawaiian Islands. This is a unique type of seal mortality that appears to result from atypical behavior of a limited number of Galapagos sharks that prey on pups in nearshore waters, often in just a few feet of water. Learn more about our monk seal pup protection efforts at French Frigate Shoals (Lalo).
Entanglement
Hawaiian monk seals have one of the highest documented entanglement rates of any pinniped species, and pups and juveniles are the most often entangled. Marine debris and derelict fishing gear are chronic forms of pollution affecting monk seal habitat, particularly in the Northwestern Hawaiian Islands. The number of monk seals found entangled each year has generally remained unchanged. Undertaken by various agencies within NOAA, the U.S. Coast Guard, and other partners, marine debris removal efforts have extracted over 800 metric tons of debris in the Northwestern Hawaiian Islands since 1996, but accumulation rates of marine debris appear to remain constant. Learn more about our Marine Debris Research and Removal in the Northwestern Hawaiian Islands.
Male Seal Aggression
A significant cause of female and juvenile monk seal mortality—and overall population decline—during the 1980s and early 1990s was by aggression from multiple male seals (especially at Laysan (Kamole) and Lisianski (Kapou) Islands). In other instances, single males have aggressively attacked and lethally injured recently weaned pups at French Frigate Shoals (Lalo) and Kure Atoll (Hōlanikū). NOAA Fisheries found that removal of specific aggressive males appears to be an effective method to address this threat. Other interventions include hazing of the aggressor, translocating young seals away from areas with the aggressive males, and treating injured seals as appropriate. Male aggression continues to be a concern, even though it tends to be episodic, geographically limited, and largely manageable provided necessary resources are available.
Habitat Loss
The loss of terrestrial habitat is a significant issue in the Northwestern Hawaiian Islands, which has mostly low-lying atolls (many islands less than 6.5 feet above sea level) subject to beach loss from storm erosion and sea level rise. Some significant habitat loss—such as the disappearance of Whale-Skate and Trig Islands at French Frigate Shoals (Lalo) which were previously primary pupping sites—has already occurred, and sea level rise over the longer term may threaten a large portion of the resting and pupping habitat in the Northwestern Hawaiian Islands.
Fishery Interactions
Since 1990, fishery management measures have eliminated interactions with monk seals in U.S.-managed commercial fisheries in the Northwestern Hawaiian Islands. But interactions in nearshore recreational and subsistence fisheries have occurred in the main Hawaiian Islands. Between 1976 and 2018, there have been up to180 documented hookings and entanglements in gill nets, which resulted in 19 monk seal deaths. However, deaths from hookings would be higher were it not for stranding response and other interventions by NOAA Fisheries. Expert fishermen, together with state and federal wildlife managers developed best practice guidance for fishermen that participate in the three main Hawaiian Islands nearshore fisheries that may interact with monk seals: spearfishing, shorecasting, and gillnet fishing.
Disease and Contaminants
One of the primary diseases of concern to Hawaiian monk seals is toxoplasmosis, a leading cause of seal death in the main Hawaiian Islands. The first case of toxoplasmosis in a Hawaiian monk seal was identified in 2004, and in sum there have been at least 13 known deaths of Hawaiian monk seals caused directly by this parasite, with two clusters of cases detected in 2018 and 2020. Seals with toxoplasmosis are usually found dead and not all carcasses are found, so it is likely that more seals have been affected than are reported. There are more cases of toxoplasmosis in females than males, which means that this disease has direct impacts on the species' reproductive potential and population growth. Unlike toxoplasmosis, which is a clear and present disease threat, morbillivirus (such as the phocine distemper virus) and West Nile Virus are of particular interest despite the fact that neither have been detected in wild Hawaiian monk seals to-date. Because Hawaiian monk seals do not have antibodies to morbilliviruses or West Nile Virus, their introduction could have a substantial effect on the population. The focus is therefore in early detection and prevention, and Hawaiian monk seals have been routinely vaccinated against morbillivirus since 2016. Other infections that are sometimes detected in Hawaiian monk seals include Brucella, herpesvirus, and Leptospira, and their significance varies but is generally not thought to have population level impacts. Persistent organic pollutants and other contaminants in Hawaiian monk seals are below the levels that have been identified as causing health effects in other marine mammal species.
Human-Seal Interactions
Intentional feeding, disturbance of sleeping or resting seals (including dog attacks), boat or vehicle strikes, and other direct human interactions, such as swimming with juvenile seals, has become a serious concern for the main Hawaiian Islands population. Beaches that are popular for human recreation are increasingly used by monk seals for "hauling out" (resting) and molting, and some female monk seals are also pupping on popular recreational beaches. During these pupping events, mother-pup pairs remain on the beach to nurse for up to 7 weeks, at which time they're particularly vulnerable to human disturbance. This also presents a serious human safety concern, as mother seals are protective and aggressive. Human-seal interactions pose both a threat to human and seal safety and have necessitated the relocation of "conditioned" seals to remote locations in some cases.
Intentional Killing
Intentional killing of seals is an extreme example of negative human impacts in the main Hawaiian Islands. As of 2018, at least four seals have died from apparent gunshots (including one pregnant female) and eight from blunt force trauma. These events are ongoing and of serious concern.
Scientific Classification
Kingdom
Animalia
Phylum
Chordata
Class
Mammalia
Order
Carnivora
Family
Phocidae
Genus
Neomonachus
Species
schauinslandi
Last updated by NOAA Fisheries on 06/11/2024
What We Do
Conservation & Management
We use innovative science to develop targeted strategies and management efforts to recover the Hawaiian monk seal populations. Our recovery planning process is designed to comprehensively address both ecological and human-caused threats. Our work includes:
Responding to monk seal haul-outs and strandings.
Providing outreach and education, and fostering a culture of human-seal coexistence.
Protecting habitat and designating critical habitat.
Ensuring natural population growth and reducing human-seal interactions.
Supporting monk seal rehabilitation and veterinary care.
Vaccinating wild Hawaiian monk seals against morbillivirus.
Translocating weaned pups from areas with high risk of Galapagos shark predation to safer islets.
Addressing injuries and mortalities caused by aggressive male seals.
Our scientists work to enhance the recovery of Hawaiian monk seals by investigating threats to their survival and working to mitigate factors impeding species recovery. Our work includes:
Monitoring population trends and evaluating threats.
Tracking the success and effectiveness of population enhancement activities.
Studying monk seal foraging behavior and the connections between feeding and commercial/recreational fisheries.
Investigating monk seal diseases and parasites.
Conducting genetic research to advance knowledge of seal health, population dynamics, and diet.
Responding to sick, entangled, hooked, and/or injured seals.
Descriptive location—including island, beach name, and GPS coordinates (if available).
Estimated size of seal (length).
Identifying characteristics (flipper tags, scars, or other markings).
Seal's behavior—including interactions with people and other animals.
Photos (if possible).
Keep Your Distance
It's natural for monk seals to come ashore or haul out on the beach for long periods of time. Please give them the space they need to rest and don't attempt to push them back into the water. If approached by a seal, move away to avoid interaction. If you're in the ocean, cautiously exit the water.
Respect any roped off areas or signage that indicate the presence of a monk seal on the beach. When observing resting monk seals, follow the “rule of thumb” to figure out how much space to give them. Simply make a “thumbs-up” gesture and extend your arm out straight in front of you, with your thumb parallel to the ground. If your thumb covers the entire seal, you are far enough away.
Report a sick, injured, entangled, stranded, or dead animal to the Pacific Islands NOAA Marine Wildlife Hotline at (888) 256-9840. Reporting ensures that professional responders and scientists know about it and can take appropriate action. Numerous organizations around the Pacific Islands are trained to receive reports and respond when necessary.
Reduce Nearshore Fishery Interactions
Serious and sometimes fatal monk seal injuries can occur when these animals are accidentally hooked. Here are some tips to prevent injuries to monk seals:
Use barbless circle hooks.
Reuse or share your leftover bait—don’t feed seals.
Reel in your line if monk seals are near.
Change locations if seals show interest in your bait or catch.
Marylou Staman conducts green sea turtle surveys at Lalo in the Papahānaumokuākea Marine National Monument. More than 90 percent of the Hawaiian green sea turtle population nests at Lalo (French Frigate Shoals). Credit: NOAA Fisheries. Taken under U.S. Fish and Wildlife Service Permit #TE-72088A-3 and Papahānaumokuākea Marine National Monument Co-Manager’s Permit.
At first glance, seals (true or “earless seals”) and sea lions look fairly similar. Taking a closer look, these are some of the general differences to tell these animals, such as on the harbor seal (left) and California sea lion (right) pictured above.
The Hawaiian monk seal is one of NOAA Fisheries' Species in the Spotlight. This initiative is a concerted, agency-wide effort launched in 2015 to spotlight and save the most highly at-risk marine species.
Image
The Hawaiian monk seal is the last surviving species in its genus, and is endemic to the 1,500-mile long Hawaiian Islands archipelago, from Hawai'i Island to Kure Atoll (Hōlanikū).
Only about 1,570 Hawaiian monk seals are left in the world and their population is about one-third of historic levels. With numbers that small, the life of every seal can be measured in its impact on the population growth or decline. Focused efforts and heightened partnerships are essential to stabilizing and preventing the extinction of the Hawaiian monk seal. There are inherent challenges to conserving and recovering the Hawaiian monk seal across such an expansive and remote area, especially with a range of ecological and anthropogenic threats affecting the population. Even so, NOAA Fisheries is better poised than ever to save Hawaiian monk seals from extinction and advance recovery.
Threats
In the main Hawaiian Islands, the primary threats Hawaiian monk seals face are fisheries interactions, intentional harm by humans, and disease, particularly toxoplasmosis, which is now a leading cause of Hawaiian monk seal mortality and a growing concern in the populated main Hawaiian Islands. Toxoplasmosis is a disease caused by a parasite that enters the environment via cat feces and can be transmitted to seals via contaminated water or prey.
In the Northwestern Hawaiian Islands, Hawaiian monk seals face different primary threats, including food limitation for juveniles and sub-adults, entanglement in marine debris or fishing gear, and shark predation.
Other threats to Hawaiian monk seals include loss of haul-out and pupping beaches due to erosion in the Northwestern Hawaiian Islands, disease outbreaks, male aggression towards females, and low genetic diversity.
Hawaiian monk seals face threats that include food limitations in the Northwestern Hawaiian Islands, especially for juveniles and sub-adults, shark predation, entanglement in marine debris, and human interactions, especially in the main Hawaiian Islands. These human interactions include bycatch in fishing gear, mother-pup disturbance on beaches, and exposure to disease. Other threats to Hawaiian monk seals include loss of haul-out and pupping beaches due to erosion in the Northwestern Hawaiian Islands, disease outbreaks, and male aggression towards females.
Species Recovery
Although much more work remains before the species is recovered, NOAA Fisheries and our partners have made significant headway in reducing extinction risks thus far. With more than 30 years of research and management experience with Hawaiian monk seals, NOAA Fisheries is currently working across the archipelago to address the population decline, and recovery actions are making a measurable difference—up to 30 percent of the monk seals in the population today are alive as a result of direct recovery interventions to save individual seals and allow them to have future offspring. Over this time period, the rate of monk seal population decline has been cut in half.
Saving this species starts with individual seals. Because of their value to the population growth potential, many monk seal recovery efforts focus on young and reproductive females. One example that highlights the success and impacts of these actions is R5AY, fondly known locally as "Honey Girl." This seal had seven pups, six of which were also female, by the time she was 15 years old. In 2012, she was found extremely emaciated with hook-and-line entanglement damage so extensive that NOAA Fisheries needed to intervene. Through this life-saving intervention, this story has a happy ending—Honey Girl survived and went on to successfully birth two more (female) pups to date. Without the efforts of NOAA Fisheries and our partners, Honey Girl, and other seals like her, would have died and the population trend would be much worse.
NOAA Fisheries is prepared with the plans, permits, and key stakeholder support in place to execute a new recovery initiative that is expected to reverse the species decline within 5 years. In 2014, NOAA Fisheries received a new ESA-MMPA permit to implement these new and expanded recovery actions. We also have reorganized the Monk Seal Recovery Team to assist with implementation and, with their help, released a Main Hawaiian Islands Hawaiian Monk Seal Management Plan (PDF, 72 pages) in 2016.
We will continue to work with our partners to implement priority recovery actions to accelerate monk seal recovery:
Human Dimensions of Monk Seal Recovery Implementation and Community Empowerment including working with communities and stakeholders to recover the species, institute grant programs, and integrate Native Hawaiian traditional resource management values and practices into the efforts.
Northwestern Hawaiian Island Research and Recovery Initiatives including maintaining Northwestern Hawaiian Island Recovery Camps at optimal levels to maximize the number of seals benefiting from interventions and ensuring robust data collection, while expanding recovery activities, and initiating critical research on the effects of climate change on monk seals.
Health Assessment, Monitoring, and Emerging Disease Research and Prevention including increased disease monitoring and health assessments, research on diseases and mitigation strategies, implementation of a vaccination plan to prevent disease outbreaks, and establishing a network of partners to prevent and manage the threats of disease.
Research, Management, and Mitigation of Human-Seal Interactions by developing a consortium of partners to mitigate seal-fisheries interactions, developing tools and strategies to address concerning behaviors in monk seals, and implementing targeted engagement strategies to effectively promote coexistence around monk seals.
Hawaiian Monk Seal Recovery Program Infrastructure including hiring additional staff, equipment, tools, and consumables to fully implement recovery initiatives.
NOAA Fisheries is at a crucial juncture where continued commitment and investment in new monk seal recovery efforts will yield significant benefits for both monk seals and our stakeholders, including local fisheries and communities. We are developing a 5-year plan of action for this species that builds on the recovery plan and details the focused efforts that are needed over the next 5 years. Through continued commitment and dedication, we can reverse population trends and increase the chances that this rare seal will survive, and future generations can enjoy and co-exist with monk seals for years to come.
Improving survival of juvenile and adult females in the Northwestern Hawaiian Islands.
Managing and mitigating human interactions to ensure natural population growth and minimize conflict.
Addressing diseases with population level impacts.
In the first 5 years of the Species in the Spotlight initiative, we took important steps that contributed to stabilizing this species and preventing its further decline. These steps have included:
Launching the first-ever effort to vaccinate a wild population for morbillivirus and vaccinating over 700 monk seals.
De-hooking, disentangling, and rehabilitating 154 seals to improve survival.
Increasing community awareness, with more than 9,000 sightings of monk seals called into public hotlines in a single year.
Through continued commitment and dedication, we can support the recent positive population trends and increase the chances that this rare seal will survive, so future generations can enjoy and co-exist with monk seals for years to come.
2017 Species in the Spotlight Hero Award
Since opening in 2014, The Marine Mammal Center's Ke Kai Ola facility has played a critical role in Hawaiian monk seal recovery. The hospital is unique in that it is entirely dedicated to rehabilitating Hawaii's endemic and endangered seal. The Marine Mammal Center has been a valuable partner for many years, with decades of experience rehabilitating pinnipeds in California. With the opening of the Hawaii Island facility, rehabilitation became an option for many more seals. The facility helped open a new chapter in Hawaiian monk seal conservation and recovery.
The U.S. Coast Guard has partnered with the Pacific Islands Marine Mammal Health and Stranding Response Program since 2008, and responded to more than 50 requests to transport seals between islands between 2008 and 2019. These efforts translate into an excess of $450,000 in dedicated operational and staff support, and have made an enormous difference for the survival of Hawaiian monk seals.
Diane Pike has volunteered countless hours to the conservation of Hawaiian monk seals since 2008. She filled the role of marine mammal response coordinator on Molokai for over a decade, and in 2019, she stepped in to assist at Kalaupapa National Historical Park during a period of staff transition, helping to bring new staff up to speed and assisting with monitoring and tagging a large cohort of pups born in the Park that year. Diane’s recent “retirement” from monk seal recovery work marks the end of an era, and she is leaving things far better than she found them.
Hawaiʻi Marine Animal Response (HMAR) operates on the islands of Oʻahu and Molokaʻi. Since partnering with NOAA in 2016, their 80+ volunteers, interns, and staff have spent countless hours conducting field responses for Hawaiian monk seals. HMAR has responded to stranded seals, newborn pups, monitored injured and compromised individuals, helped to collect important health and stranding response data, and developed unique education projects for community members. The dedication of HMAR’s staff and volunteers is an inspiration, and they have played a big role in the significant increase in public awareness and support for Hawaiian monk seal conservation.
Hawaiian monk seals are protected under the Endangered Species Act (ESA), the Marine Mammal Protection Act (MMPA), and Hawai'i state law. They have been listed as endangered under the ESA since 1976. The Hawaiian monk seal is endemic to the Hawaiian Islands archipelago and Johnston Atoll, meaning they are native and exist nowhere else on Earth. NOAA Fisheries is working to protect this species in many ways, with the goal that its population will increase.
Recovery Planning and Implementation
Recovery Action
Under the ESA, NOAA Fisheries is required to develop and implement recovery plans for the conservation and survival of listed species. The ultimate goal of the Recovery Plan for the Hawaiian Monk Seal is to recover the species, with an interim goal of down-listing its status from endangered to threatened.
The major actions in the recovery plan are:
Investigate and mitigate factors affecting food limitation
Prevent entanglement of monk seals
Reduce shark predation on monk seals
Conserve Hawaiian monk seal habitat
Reduce Hawaiian monk seal interaction with fisheries
Reduce male aggression toward pups/immature seals and adult females
Reduce the likelihood of human disturbance
Investigate and develop response to biotoxin impacts
Reduce impacts from compromised and grounded vessels
Implement the Recovery Program for the Hawaiian monk seal
Hawaiian monk seal resting on the beach at French Frigate Shoals (Lalo) in the Northwestern Hawaiian Islands.
Implementation
NOAA Fisheries is committed to implementing the Hawaiian Monk Seal Recovery Plan, focusing on the overarching recovery strategies listed above. Actions being undertaken to implement the plan:
Coordination of NOAA, non-governmental organizations, and other federal, state, and local agencies to facilitate monk seal recovery.
Reduction of mortality factors, including shark predation, male aggression, and risk of exposure to infectious diseases.
Conservation of monk seal habitat.
Development of comprehensive outreach and education programs focused on minimizing human disturbance and other adverse impacts and maximizing public support for monk seal conservation.
Coordination of volunteer groups in the main Hawaiian Islands to facilitate monitoring and response for Hawaiian monk seal pupping events and haul-outs.
In recent years, NOAA Fisheries has developed additional strategic implementation plans that focus on partnerships and collaboration, and on issues affecting the main Hawaiian Islands monk seal population:
The designation of an area as critical habitat does not create a closed area, marine protected area, refuge, wilderness reserve, preservation, or other conservation area; nor does the designation affect land ownership. Federal agencies that undertake, fund, or permit activities that may affect these designated critical habitat areas are required to consult with NOAA Fisheries to ensure that their actions do not adversely modify or destroy designated critical habitat.
In 2008, NOAA Fisheries received a petition to revise critical habitat for the Hawaiian monk seal—the terrestrial and marine areas the mammal needs to survive and recover—requesting the 1988 designation be extended in the Northwestern Hawaiian Islands and include new areas in the main Hawaiian Islands. Since the original critical habitat designation, new information became available regarding monk seal habitat use revealing that monk seals forage at greater depths than previously thought and that they successfully utilize habitat in the main Hawaiian Islands.
NOAA Fisheries revised the Hawaiian monk seal critical habitat to further describe habitat features and areas that support Hawaiian monk seal conservation. Specific areas designated include 16 occupied areas within the range of the Hawaiian monk seal. These areas contain one or more features essential to Hawaiian monk seal conservation, including:
Preferred pupping and nursing areas
Significant haul-out areas
Marine foraging areas out to 200 meters in depth
In 2015, NOAA Fisheries issued the final rule to revise the Hawaiian monk seal critical habitat, expanding the previous designation in the Northwestern Hawaiian Islands and identifying new key beach areas and marine-foraging areas in the main Hawaiian Islands.
Areas Included in the Final Critical Habitat Designation
NORTHWESTERN HAWAIIAN ISLANDS (Hawaiian names in parenthesis)
Critical habitat in the Northwestern Hawaiian Islands includes all beach areas, sand spits, and islets, including all beach crest vegetation to its deepest extent inland as well as the seafloor and marine habitat 10 meters in height above the seafloor from the shoreline out to the 200-meter depth contour around:
Kure Atoll (Hōlanikū)
Midway Atoll (Kuaihelani)
Pearl and Hermes Reef (Manawai)
Lisianski Island (Kapou)
Laysan Island (Kamole)
Maro Reef (Kamokuokamohoali‘i)
Gardner Pinnacles (‘Ōnūnui)
French Frigate Shoals (Lalo)
Necker Island (Mokumanamana)
Nihoa Island
MAIN HAWAIIAN ISLANDS
Critical habitat in the main Hawaiian Islands includes the seafloor and marine habitat to 10 meters above the seafloor from the 200-meter depth contour through the shoreline and extending into terrestrial habitat 5 meters inland from the shoreline between identified boundary points around the following islands:
Kaula Island (includes marine habitat only)
Niʻihau (includes marine habitat from 10 to 200 meters in depth)
Kauaʻi
Oʻahu
Maui Nui (including Kahoʻolawe, Lānaʻi, Maui, and Molokaʻi)
Hawaiʻi Island
Conservation Efforts
For each threat identified as a source of negative impacts to monk seals (see the Threats section on Overview), NOAA Fisheries, with assistance from our partners, has developed and implemented targeted conservation and recovery efforts to address each threat. We have also developed broader management and outreach strategies that seek to engage the general public as an active part of monk seal recovery.
Overseeing Marine Mammal Health and Stranding Response
We work with volunteer networks in all coastal states to respond to marine mammal strandings including all pinnipeds. 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.
Hawaiian Monk Seals 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.
The Pacific Islands Marine Mammal Response Network responds to strandings and haul-outs of all marine mammals, including monk seals. NOAA Fisheries manages the Network in partnership with several government agencies, including the Hawaiʻi Department of Land and Natural Resources, the Hawaiian Islands Humpback Whale National Marine Sanctuary, University of Hawaiʻi at Mānoa, the U.S. Coast Guard, and the National Park Service. Network volunteers, managed directly by NOAA Fisheries and/or our partners, donate thousands of hours to public education and day-to-day human-seal management in the main Hawaiian Islands.
Volunteers assist with the following:
Responding to seals that haul out to rest by setting up "seal resting areas" and using them as a platform to educate the public about monk seal biology, conservation, and responsible wildlife viewing practices, which helps to deter potential disturbance.
Monitoring monk seal pupping and molting events.
Reporting seals in distress (due to fish hook injury, entanglement, or otherwise) and standing by until arrival of certified NOAA assistance.
Searching for and long-term monitoring of seals of concern (seals reported with injuries, hookings, entanglements, behavioral concerns, etc.) and providing NOAA with observation data on these animals.
Visiting schools, festivals, local businesses, and other venues to provide public education and outreach regarding the ecology and conservation of Hawaiian monk seals.
Implementing Targeted Conservation Strategies
Food Limitation
Our work includes:
Translocation of seals to other islands or atolls with improved foraging conditions.
Captive rehabilitation of malnourished animals.
Of note, NOAA’s partnership with Ke Kai Ola, a facility built by The Marine Mammal Center in Kona, Hawai'i in 2014, has opened up a new world of rehabilitation possibilities for monk seals. In 2017, Ke Kai Ola was recognized as a NOAA Species in the Spotlight Hero for their contributions to monk seal conservation and recovery.
Shark Predation
Our work includes:
Translocation of newly weaned pups to areas with low shark predation risk.
Limited lethal removal of Galapagos sharks from nearshore pupping habitat.
Entanglement in Marine Debris
Our work includes:
Disentangling seals and removal of marine debris from beaches and marine habitat.
Adult Male Aggression
Our work includes:
Treating injured seals when appropriate.
Hazing of identified aggressors.
Translocating pups from areas where aggressive males frequent.
Removing the aggressive males.
Habitat Loss
Our work includes:
Continued monitoring to assist in planning mitigation strategies necessary, particularly for the Northwestern Hawaiian Islands.
Human-Seal Interactions (Including Fisheries)
Our work includes:
Education and outreach to prevent/minimize human-seal interactions.
Applying behavioral conditioning, translocating, or bringing into captivity seals that pose a human safety risk.
Dehooking seals.
Encouraging fishermen to use barbless hooks and to avoid fishing when a seal is in the area.
Monitoring health, including disease, parasitic infection, and toxin screening.
Providing appropriate medical treatment (including deworming).
Continuing vaccination research and response planning.
Coordinating Volunteer Participation
We coordinate volunteer groups in the main Hawaiian Islands to assist with monitoring and response for monk seal pupping events and haul-outs. Volunteers help put up signs near hauled-out monk seals to help alert the public to their presence and help prevent disturbance. They also educate beachgoers about monk seal natural history and responsible viewing of this endangered species.
Volunteers also assist NOAA’s monk seal researchers to assess the population of this endangered species by counting seals on beaches across all of the main Hawaiian Islands.
Evaluating the Environmental, Social, and Economic Effects of the Monk Seal Recovery Program
In compliance with the National Environmental Policy Act, NOAA Fisheries prepared and published a programmatic environmental impact statementin 2014. This comprehensive review of the monk seal recovery program describes and analyzes a suite of research and enhancement (management) actions proposed by NOAA Fisheries to promote recovery of endangered Hawaiian monk seals.
Education and Outreach
Volunteers help put up signs near hauled-out monk seals to help protect them from disturbance and educate beachgoers about monk seal natural history and responsible viewing of this endangered species.
We, NOAA Fisheries, issue a final rule to revise the critical habitat for the Hawaiian monk seal (Neomonachus schauinslandi) pursuant to the Endangered Species Act. Specific areas for designation include sixteen occupied areas within the range of the…
We, NOAA Fisheries, announce the revised taxonomy of Monachus schauinslandi (Hawaiian monk seal) under the Endangered Species Act of 1973, as amended (ESA). We are revising the Enumeration of endangered marine and anadromous species and…
NOAA Fisheries announces the availability of the “Final Programmatic Environmental Impact Statement (PEIS) for Hawaiian monk seal Recovery Actions.” Publication of this notice begins the official public comment period for the Final PEIS. The…
NOAA Fisheries announces the adoption of an Endangered Species Act (ESA) Recovery Plan (Recovery Plan) and 5-year review for the Hawaiian monk seal (Monachus schauinslandi). The Recovery Plan contains revisions and additions in consideration of public…
NOAA Fisheries issued an incidental harassment authorization (IHA) to Lamont-Doherty Earth Observatory of Columbia University (L-DEO) to incidentally take marine mammals during a Marine Geophysical Survey.
OAA Fisheries, upon request from the U.S. Navy, issues these regulations pursuant to the Marine Mammal Protection Act to govern the taking of marine mammals incidental to the use of Surveillance Towed Array Sensor Systems Low Frequency Active (SURTASS LFA
NOAA Fisheries issued regulations under the MMPA to govern the unintentional taking of marine mammals incidental to training and testing activities conducted in the Hawaii-Southern California Training and Testing (HSTT) Study Area from December
NOAA Fisheries uses innovative science to explore monk seal biology and interactions with humans and the environment, and apply the best available science to guide our management and recovery plans for monk seals. Our Hawaiian Monk Seal Research Program leads these efforts.
The Hawaiian Monk Seal Research Program
Our overarching goal is to achieve an optimal and sustainable monk seal population. This program works together with outside collaborators on five key research and conservation initiatives designed to address the recovery strategies outlined in the Hawaiian Monk Seal Recovery Plan.
Research and Conservation Initiatives
Five key research and conservation initiatives are undertaken by integrated teams of Hawaiian Monk Seal Research Program personnel and collaborators to further identify impediments to survival and respond with appropriate science-based conservation measures.
Population Assessment and Enhancement Research
The work performed under this initiative provides annual high-resolution information from each monk seal subpopulation required to assess the species status, population trends, and current threats. Survival enhancement activities are implemented and tracked to evaluate their effectiveness.
Foraging and Fisheries Interactions Research
This initiative aims to characterize the foraging ecology of monk seals by evaluating monk seal diet, foraging behavior and habitat use, and via examination of ecological links affecting monk seal foraging. Additional studies include quantifying the level and types of direct and indirect interactions with fisheries and determining ways to mitigate them to the benefit of both seals and fishermen.
Survival Enhancement Research and Activities
This initiative focuses on developing effective tools and activities to mitigate threats, and thus enhance monk seal survival throughout its range
Health and Disease Research and Emergency Response
Our scientists investigate the role infectious diseases, parasites, and toxins play in the recovery of monk seals. Other activities include critical response for compromised seals (e.g., hooked, entangled, sick, and/or injured).
Genetics Research
Our scientists use molecular techniques to advance knowledge of Hawaiian monk seal health, population dynamics, and diet.
Population Status/Stock Assessment
The prolonged and steep decline of Hawaiian monk seal populations has occurred more or less continuously since the 1950s. However, there have been some relatively recent encouraging developments, including:
The population is finally growing at an average rate of about 2 percent per year since 2013.
Promising advances in juvenile seal survival enhancement research and local community engagement.
The best estimate of the current total Hawaiian monk seal population is 1,400 seals—about 1,100 in the Northwestern Hawaiian Islands (from Nihoa to Kure Atoll (Hōlanikū)), and about 300 in the main Hawaiian Islands (from Ni'ihau to Hawai'i Island).
Researchers categorized the causes of seal deaths since 1992 to determine which are most harmful to the recovery of this endangered population. This study, conducted by NOAA scientists and colleagues, summarized the causes of monk seal deaths in the main Hawaiian Islands from 1992 to 2019 (114 seals). It found that more than half of the deaths were caused by humans.
Latest update looks at the Hawaiian monk seal population, pups and juveniles, and threat mitigation from the 2019 field season; highlighting the need for continued conservation.
Hawaiian Monk Seal Movements Among Islands and Atolls - It was once assumed that monk seals did not travel between the Northwestern Hawaiian Islands and the main Hawaiian Islands, but research now shows that in rare cases they do, and even make it down to Johnston Atoll.
The Role of Diet as a Driver of Divergent Population Trends - Monk seals in the Northwestern Hawaiian Islands and main Hawaiian Islands eat a similar diet, but seals in the main Hawaiian Islands may experience less competition for food. In addition, prey that may be more bountiful and better quality, allowing the main Hawaiian Islands population to increase while the Northwestern Hawaiian Islands population continues to decrease.
Non-Lethal Efforts to Deter Shark Predation of Monk Seal Pups - Monk seal pups at French Frigate Shoals are heavily preyed upon by Galapagos sharks, but it’s unclear if non-lethal efforts to deter this behavior are effective. However, translocating newly weaned pups to areas with less shark predation has proven beneficial to pup survival.
Large-scale and sustained removal of abandoned, lost, or otherwise discarded fishing gear meaningfully benefits marine ecosystems and has the potential to be transformational in restoration efforts.
In this analysis, we quantify not only the frequency of specific causes‐of‐death (CODs) among main Hawaiian Island monk seals, but also assess the impact of individual CODs on the intrinsic growth rate, λ, of this population.