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FAQs on the 2013-2015 Bottlenose Dolphin UME in the Mid-Atlantic

NOAA Fisheries has declared an Unusual Mortality Event (UME) for bottlenose dolphins along the Atlantic Coast including the states of New York, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia and Florida beginning in early July 2013.

Q: What is an Unusual Mortality Event?

A: An UME is defined under the MMPA as a stranding event that is unexpected, involves a significant die-off of any marine mammal population, and demands immediate response. There are seven criteria used to determine whether a mortality event is "unusual." If the Working Group on Marine Mammal Unusual Mortality Events (Working Group), a group of marine mammal health experts, determines that an event meets one or more of the criteria, then an official UME is declared.

Q: What criteria have been met?

A: The Working Group concluded that at least one of the seven criteria established for designation of an UME have been met. These mortalities are unusual because there is a marked increase in the magnitude or a marked change in the nature of morbidity, mortality or strandings when compared with prior records.

Q: How widespread is this Unusual Mortality Event?

A: Increased strandings of bottlenose dolphins have occurred along the Atlantic Coast including the states of New York, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia and Florida.  Virginia, North Carolina and Florida have had the most strandings to date. 

Q: When did the first reports of increased strandings of bottlenose dolphins come in?

A: In early July 2013, the Virginia Aquarium, the Marine Mammal Stranding Center in New Jersey, and Riverhead Foundation for Marine Research and Preservation in New York started to notice an increase in bottlenose dolphin strandings in the region.  Since that time the peak of strandings occurred between July 2013 and March 2014, although strandings remain elevated in North Carolina, South Carolina, and North Florida and sporadic strandings are still ongoing in the other states.

Q: What are the findings in stranded animals?

A: At this time, all age classes of bottlenose dolphins are involved in the event.  The majority of animals are stranding dead (96%) with some carcasses found fresh dead but the majority of carcasses found on the beach are moderately to severely decomposed.  Many dolphins have presented with lesions on their skin, mouth, joints, lungs or brain and ranged in body condition from good to thin.  Based upon preliminary diagnostic testing and discussion with disease experts the tentative cause of this UME is being attributed to cetacean morbillivirus. However, the investigation is still ongoing and additional contributory factors to the UME are under investigation including other pathogens, biotoxins, contaminants, range expansion, etc.

Q: Have other marine mammals been affected by this die-off event?

A: We have had several of the other stranded cetacean species test positive for dolphin morbillivirus via polymerase chain reaction testing including: three positive humpback whales, one positive fin whale, three positive pygmy sperm whales, one positive minke whale, and one positive striped dolphin.  At this time, only the one striped dolphin had histopathologic findings consistent with morbilliviral clinical disease.  We have not had elevated strandings in the other cetacean species.

Q: What is happening to live stranded cetaceans during this event?

A: Approximately 4% of the bottlenose dolphins in this event stranded live, which is about 2-3 times above normal for this geographic area. The live animals stranding in this event have been ill and most have died shortly after stranding.  In general, most bottlenose dolphins that strand live as single stranding events are ill and in need of medical attention. 

We reviewed the Policies and Best Practices for Marine Mammal Stranding Response, Rehabilitation, and Release including the Standards for Rehabilitation Facilities and evaluated the risk and welfare concerns associated with rehabilitating any live stranded cetacean found within the UME impacted area.  Since morbillivirus is a highly contagious and lethal disease, all cetacean rehabilitation has been halted along the Atlantic seaboard starting in September 2013 for the Northeastern states and November 2013 for the Southeastern states (through the FL Keys).  Some of our reasons for not authorizing live cetacean rehabilitation in the UME area are as follows:

To date, live dolphins stranding during this UME have shown severe illness including lung, brain, and skin infections. Many dolphins have died on the beach prior to transport or to administration of euthanasia, indicating severe debilitation making them poor candidates for rehabilitation.

Q: How many populations of dolphins are being affected?

A: There are four potential dolphin populations that may be in the same vicinity as the UME-related strandings at this time. These bottlenose dolphin populations include the Southern Migratory Coastal stock, the Northern Migratory Coastal stock, the Northern North Carolina Estuarine System stock, and the Offshore stock. It is still unknown which particular population or populations are being affected.

Q: How many dolphins are in these dolphin populations? How many animals are at risk?

A: The best population estimates for these stocks are published annually in the NOAA Fisheries Stock Assessment Reports. The most recent published 2012 Stock Assessment Report estimates that 9,604 dolphins belong to the Northern Migratory Coastal stock, 12,482 dolphins belong to the Southern Migratory Coastal stock, 950 dolphins belong to the Northern North Carolina Estuarine System Stock, and 81,588 dolphins belong to the Offshore stock. It is still unclear at this time which particular stock or stocks of dolphins are being affected, so an estimate of how many animals are at risk is not known.

Q: How do scientists figure out which population the stranded dolphins are from?

A: Whenever possible, responders collect samples from stranded dolphins. Samples may include pieces of blubber, skin, or a tooth. Once these samples are analyzed for genetics or chemical signature, scientists may be able to identify to which population the affected dolphins belong.

Q: Why is it important to identify which population the affected dolphins are from?

A: Knowing the population of origin for stranded dolphins is crucial to understanding the impact on the population(s). Understanding the impact (i.e., how many animals died out of that population) can help managers and scientists better predict and manage recovery of the population(s).

Q: What is the range of these populations?

A: The current understanding of these population movements are based on limited data and small sample sizes. However, our best understanding is that the Northern Migratory Coastal Stock ranges as far north as Long Island, New York in the summer months and moves south to North Carolina coastal waters during the winter months. We believe that the Southern Migratory Coastal stock may range as far north as Virginia state waters in summer months and move as far south as northern Florida during the winter months. The Northern North Carolina Estuarine System stock mostly ranges within the inshore and coastal waters of North Carolina, but some animals from this population may move into the Chesapeake Bay during summer and early fall. The Offshore stock of dolphins is mainly found in deeper water along the Atlantic continental shelf edge, all along the east coast.

Q: Can this epidemic spread to other populations of dolphins?

A: Based on our best understanding of these dolphins, some of these populations (Northern Migratory Coastal and Southern Migratory Coastal) migrate seasonally. The Southern Migratory Coastal stock may migrate south along the east coast to as far south as northern Florida during the winter months. There is some concern that this migratory population may occasionally mix with other coastal and inshore populations of dolphins when migrating south, potentially exposing other animals to the virus. 

In the summer of 2014, elevated strandings of Bay, Sound, Estuary dolphins occurred in the St John’s River and Northern Indian River Lagoon System (specifically Mosquito Lagoon) along the east coast of Florida.  Several of these stranded dolphins were positive for dolphin morbillivirus.  It is not yet known what impact dolphin morbillivirus will have on dolphins in the Indian River Lagoon and St. John’s River; however, dolphins in the northern and central Indian River Lagoon were part of a separate Unusual Mortality Event in 2013 and we are closely monitoring stranding rates in both systems.

Q: What are the next steps in the investigation now that an Unusual Mortality Event has been declared?

A: As part of the UME investigation process, an independent team of scientists (Investigative Team) is being assembled to coordinate with the Working Group to review the data collected and to determine potential next steps. The Investigative Team will develop the investigative response plan. The investigation may require months, or even years of data collection, analysis, and interpretation.

Q: What additional resources are now available to pursue the investigation, since an Unusual Mortality Event has been declared?

A: An UME declaration provides additional expertise from the Working Group (an international and multi-disciplinary team of scientists), additional partners, and access to additional funding through the National Contingency Fund. In addition, a detailed investigative response plan for the investigation will be developed that may include more targeted necropsies; further testing of samples for biotoxins, infectious agents and chemicals, environmental and biological evaluations and diagnostic pathology services. Finally, this process will provide national and international scientific review of findings and interpretations.

Q: Will you be collecting additional biological and environmental information?

A: The Stranding Network will continue to collect and analyze samples as needed to evaluate the situation. As the evidence indicates, additional biological and environmental sampling will take place as resources allow.

Q: When will you have some results to share?

A: The Investigative Team is in the process of developing an investigative response plan for collection and analyses of samples from stranded animals. Blood and tissues samples will be tested for infectious agents such as viruses, bacteria and fungi as well as non-infectious agents such as biotoxins. You can track the progress of the investigation from our UME website.

Q: What is the risk to humans?

A: Bottlenose dolphins are wild animals and may injure people if approached closely. It is not clear at this time if there is any infectious disease risk to human health through contact with these animals but we do share common pathogens. Do not approach dead or live marine mammals on the beach or floating in waters along our coasts.

Q: Have there been any specific instances of humans contracting a disease from the bottlenose dolphins?

A: To date, no cases of human illness have been reported from this current event.

Q. Can I catch what is affecting the dolphins from swimming?

A. To our knowledge, not at this time, but as a caution, people should not swim with open wounds or in the immediate area where a stranded animal is found.

Q: Are there any risks to pets?

A: Dolphins, like other marine mammals (whales, porpoises, seals and sea lions), are protected under the Marine Mammal Protection Act. Pets should always be kept away from marine mammals, particularly stranded live or dead marine mammals. To our knowledge cetacean morbillivirus is not infective to pets but the dolphins may have other secondary bacterial or fungal pathogens.  Dogs and cats can share infectious diseases with marine mammals and should not be allowed to approach live or dead ones, or to consume dead marine mammals or their parts. NOAA Fisheries recommends contacting your pet’s veterinarian to discuss the potential risk to pets in your local area. For more information, visit the CDC website.

Q: How many bottlenose dolphin Unusual Mortality Events have previously occurred in the Mid-Atlantic Region?

A: No previous UME has occurred in all of the Mid-Atlantic States involved in this UME, but nine previous UMEs have occurred in some of the states involved in the present UME. These other events involved bottlenose dolphin or other small cetacean species. In eight of the cases, the cause of the die off was investigated but not determined, and in one case the cause was attributed to ecological factors. To date, 60 UMEs have been formally declared in U.S. waters since 1991 (including the current UME).

Q: How many marine Unusual Mortality Events have previously occurred in the Atlantic Ocean?

A: This is the 21st UME to occur in waters of the Atlantic since the Program was established in 1991. Previous events involved seals, manatees, bottlenose dolphins, other small cetaceans and/ or whales.

Q: What are the similarities to this event and the 1988-1987 Bottlenose Dolphin Mortality Event?

A: The 1987-1988 bottlenose dolphin mortality event occurred along the Atlantic Coast and spanned the region from New Jersey to Florida with over 700 dolphins stranding during that event (June 1987 to March 1988). The cause of this event was determined to be due to morbillivirus infection, however some animals also showed exposure to brevetoxin, a harmful algal bloom associated biotoxin uncommon to dolphins in this region.

Q: Where can I find additional information on bottlenose dolphins and other Unusual Mortality Events?

A: You can visit the following NOAA websites:

Q: What should people do if they encounter a sick dolphin stranded on the beach?

A: If members of the public find a live or dead stranded marine mammal, they should immediately call the local marine mammal stranding network who will send trained responders to evaluate the animal and take the next appropriate steps.

For additional information on how to help a stranded marine mammal, please see:

Q: What should people do if they witness harassment of a dolphin in the water or on the beach?

A: To report violations or for more information on NOAA’s Office of Law Enforcement call the toll-free number: 1-800-853-1964.

Q: What is the link, if any, of these marine mammal illness/deaths to seafood safety?

A: State and Federal Agencies continue to conduct routine testing of seafood for consumer safety while NOAA Fisheries is working with a group of wildlife researchers to test for a wide range of possible disease factors causing this bottlenose dolphin UME. No link has been established at this time between these bottlenose dolphin strandings and any potential seafood safety issues.

Q: What is the Unusual Mortality Event Contingency Fund?

A: The MMPA’s Section 405 (16 USC 1421d) establishes the Marine Mammal Unusual Mortality Event Fund and describes its purposes and how donations can be made to the Fund. The fund: “shall be available only for use by the Secretary of Commerce, in consultation with the Secretary of the Interior:

The National Contingency Plan for Response to Unusual Marine Mammal Mortality Events outlines the types of expenses that are reimbursable under the fund and the process for requesting reimbursement.

Additional information on the Unusual Mortality Event Contingency Fund can be found on our UME website.

Q: How can deposits be made into the Unusual Mortality Event Contingency Fund?

A: Deposits can be made into Fund by the following:

Updated: January 8, 2015