Frequent Questions: 2018-2019 Pinniped Unusual Mortality Event

Why was the Unusual Mortality Event Closed?

Based on a closure request provided by the Onsite Coordinator, the Working Group on Marine Mammal Unusual Mortality Events recommended closing the event. Stranding rates for the three seal species are no longer elevated, and gray and harbor seals are not stranding with clinical signs of phocine distemper virus infection. 

How widespread was this Unusual Mortality Event?

Increased strandings of gray and harbor seals extended from Maine through Rhode Island. Strandings of harp seals extended from New Hampshire through New York.

What were the dates for this UME? How many seals were included?

The Unusual Mortality Event occurred between January 1, 2018, and May 31, 2019, with a total of 2,107 seals documented. Specifically, gray seal strandings occurred from January 1, 2018, through December 31, 2018, affecting 468 seals. Harbor seal strandings occurred from May 1, 2018, through December 31, 2018, affecting 1,328 seals. Harp seal strandings occurred from November 28, 2018, through May 31, 2019, affecting 311 seals.

What do scientists believe is the most likely cause of this Unusual Mortality Event?

The investigation determined different drivers impacting the three seal species. The cause of the UME for gray and harbor seals was infection with phocine distemper virus. The cause of the UME was undetermined for harp seals but may have been related to population increases and fewer ice-related deaths among the 2018 and 2019 cohort of young harp seals. 

What is the phocine distemper virus?

The phocine distemper virus is a type of morbillivirus. Morbilliviruses are in the family Paramyxoviridae and specific morbilliviruses cause measles (in people), canine distemper (in dogs, coyotes, wolves, and seals), rinderpest (in cattle), and peste-des-petits-ruminants (goats and sheep).

Five types of morbilliviruses have been detected in marine mammals in the United States: canine distemper virus and phocine distemper virus in seals and sea otters, and in cetaceans, dolphin morbillivirus, pilot whale morbillivirus, and Longman’s beaked whale morbillivirus. 

The phocine distemper virus was first recognized in marine mammals in 1988 in Europe where 60 percent of the North Sea harbor seal population and a few hundred gray seals died. Subsequent large-scale mortality events due to phocine distemper have occurred in seals in Europe.

How do phocine distemper viruses affect seals?

The most common organs affected are the lungs and brain. Sick animals may appear thin, have respiratory difficulties due to pneumonia, such as sneezing, coughing, teary eyes, and/or exhibit abnormal behavior.

When exposed to phocine distemper viruses, some animals mount an antibody response and fight the infection. This usually protects against future infections and may reduce severity of clinical disease.

What is the risk to humans from the phocine distemper virus?

The phocine distemper virus is not a zoonotic virus and therefore is not transmissible to humans. To date, there has never been a single reported case of human infection with phocine distemper virus. It is unknown if the phocine distemper virus can be transmitted to your dog, so it is best to prevent contact between your dog and seals.

More information on diseases is available from the Centers for Disease Control.

Does eating seafood pose a risk?

No, phocine distemper viruses do not cause disease in fish, so there is no risk of catching this virus by eating fish.

Has phocine distemper virus ever been detected in seals in the northeastern U.S. before?

Yes, the first cases of phocine distemper mortalities documented in harbor seals in the United States was in 1992 on Long Island. Since that time, the phocine distemper virus has been detected at low levels in seals along the northeastern U.S. coast. 

The phocine distemper virus played a role in the mortality that occurred in the northeastern United States during the 2006 seal Unusual Mortality Event involving harbor seals, harp seals, hooded seals, and gray seals.

What is next now that the Unusual Mortality Event has been closed?

The Stranding Network will continue to respond to stranded seals. They may sample some animals for phocine distemper virus and other pathogens, when feasible. Sampling will focus on live and fresh dead seals, including those euthanized in accordance with nationally approved veterinary methods. Continued monitoring of the health of stranded animals helps marine mammal conservation and may shed light on the long-term impacts of disease outbreaks such as the one documented in this UME.

Where can I find additional information on gray, harbor, and harp seals?

You can visit the national NOAA Fisheries Protected Resources species page for more information about gray seals, harbor seals, or harp seals. You can also read about seal viewing guidelines in the Northeast.

How many seal UMEs have previously occurred along the Northeast coast?

Four previous UMEs involving harbor and/or gray seals have occurred along the Northeast coast in 1991–1992, 2003, 2006–2007 and 2011–2012.

The 1991–1992 UME was localized in Massachusetts, involved approximately 24 harbor seals and the cause of this event was suspect avian influenza virus.

The 2003 UME was localized in Maine and involved an estimated 42 harbor seals and the cause was undetermined.

The 2006–2007 UME extended from Maine to Virginia, involved approximately 1,500 seals including harbor and gray seals, and the cause of that event was the phocine distemper virus.

The 2011–2012 UME extended from Maine to Massachusetts, involved an estimated 784 seals including harbor and gray seals, and the cause of that event was avian influenza.

What should I do if I encounter a dead or live-stranded seal on the beach?

If you see a marine mammal that you believe to be sick or injured, you should not attempt to approach, touch, or handle it. Instead, contact trained and authorized responders in your area. Prompt and accurate reporting to local Stranding Network responders is essential and can make all the difference to the outcome of a response. 

When reporting a stranded marine mammal, include the following information:

• Date and time
• Location
• Number of animals
• Condition of the animal (alive or dead)
• Species (if known)
• Photos and/or videos, if taken from a safe and legal distance (50 yards)

All marine mammals are protected under the Marine Mammal Protection Act, and some are also listed under the Endangered Species Act. It is illegal for the public to harass protected species, which includes touching, handling, or closely approaching stranded marine mammals. Penalties for violating these acts can include fines and/or imprisonment.

What should I do if I witness harassment or any marine mammal violation in the water or on the beach?

To report violations, please contact NOAA’s Office of Law Enforcement at (800) 853-1964.

What is the UME Contingency Fund?

The Marine Mammal Unusual Mortality Event Fund is used by the Secretary of Commerce, in consultation with the Secretary of the Interior:

• “To make advance, partial, or progress payments under contracts or other funding mechanisms for property, supplies, salaries, services, and travel costs incurred in acting in accordance with the contingency plan issued under section 1421c(b) of this title or under the direction of an Onsite Coordinator for an unusual mortality event designated under section 1421c(a)(2)(B)(iii) of this title;
• For reimbursing any stranding network participant for costs incurred in the collection, preparation, analysis, and transportation of marine mammal tissues and samples collected with respect to an unusual mortality event for the Tissue Bank; and
• For care and maintenance of marine mammals seized under section 1374(c)(2)(D) of this title.”

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.

Learn more about the UME Contingency Fund

How can deposits be made into the UME Contingency Fund?

The following can be deposited into the fund:

• Amounts appropriated to the fund
• Other amounts appropriated to the Secretary for use with respect to UMEs
• Amounts received by the United States in the form of gifts, devises, and bequests under subsection (d) (see 16 USC 1421d(d)). 

You can use Pay.gov to donate to the UME Contingency Fund for this or other UMEs and help cover costs incurred by the Marine Mammal Stranding Network.