Frequent Questions: 2019 Ice Seal Unusual Mortality Event
Since June 1, 2018, elevated ice seal strandings have occurred in the Bering and Chukchi seas in Alaska. This event has been declared an Unusual Mortality Event (UME).
Why is NOAA involved in declaring a UME?
Conserving and restoring protected marine species is a core mission for NOAA Fisheries. NOAA Fisheries is responsible for the protection and conservation of all whales, dolphins, porpoises, seals, and sea lions under the Marine Mammal Protection Act. NOAA Fisheries relies on the best available science to implement the Marine Mammal Protection Act, including reducing the negative effects of human activities on protected species and their habitats. We develop and implement plans to guide species recovery and conservation, enforce regulations against harming protected species, and conduct high-quality science focused on conservation.
What are you announcing today?
Under the Marine Mammal Act of 1972 (as amended), NOAA is declaring an Unusual Mortality Event for bearded, ringed, and spotted seals from June 1, 2018-present in the Bering and Chukchi Seas.
What is an Unusual Mortality Event?
An Unusual Mortality Event is defined under the Marine Mammal Protection Act as a stranding event that is unexpected, involves a significant die-off of any marine mammal population, and demands an immediate response. Seven criteria determine whether a mortality event is “unusual.” If the Working Group on Marine Mammal Unusual Mortality Events (Working Group), a group of external marine mammal health experts, determines that an event meets one or more of the criteria, it forwards a recommendation to NOAA’s Assistant Administrator for Fisheries to declare an UME.
What criteria have been met?
In this case, the Working Group concluded that one of the seven criteria have been met:
1. A marked increase in the magnitude or a marked change in the nature of morbidity, mortality, or strandings when compared with prior records.
How widespread is this UME? Did the UME begin in 2018?
The Working Group recommended the UME be declared for bearded, ringed, and spotted seals in the Bering and Chukchi Seas from June 1, 2018 to present. Since June 1, 2018, NOAA Fisheries has confirmed at least 282 ice seal strandings in the Bering and Chukchi seas, along the northwest coast of Alaska. There were 119 strandings in 2018, and 163 in 2019.
Strandings from 2018 had delayed and limited supporting documentation, so the level of the increase in dead seals last year was not recognized in real-time.
Why was supporting documentation for the 2018 strandings delayed and limited?
The many stranding reports from the Bering Strait Region were delayed when they were shared with only a few people associated with the Alaska Marine Mammal Stranding Network. These stranding reports were brought to the attention of NOAA Fisheries, but mostly without pictures or specific documentation (dates, species, age class, location, etc.), and any field assessment (and sampling) would have been weeks after the stranding event. It took weeks to correctly document and sort these stranding reports as individual events leading to the delay in recognizing the increase in seal strandings in 2018.
How are stranding reports confirmed? Why are so many reports not confirmed?
Stranding reports are confirmed via documentation (specific information on the animal), photos, samples, and/or surveys by agency staff or members of our marine mammal stranding network.
Many stranded ice seals were observed by the general public. Some stranded seals were reported in a timely manner, and other strandings were reported weeks after the fact. The 130 stranded seals are an estimated total when NOAA Fisheries is told, “about a couple dozen were observed,” “we saw about 30-40 seals,’ and “I heard there were about 30 seals along that stretch of beach.” Sometimes a portion of these estimated stranded seals were confirmed. Other times NOAA Fisheries was unable to send a local expert or veterinarian to the location because the report was old.
How did the agency collect samples from the stranded seals, given that the carcasses were located in remote western Alaska locations? What samples were collected?
NOAA Fisheries Alaska Marine Mammal Stranding Network members live in or were flown to Kivalina, Kotlik, Kotzebue, Nome, Point Hope, Shishmaref, and Wales to investigate reports about stranded ice seals. Samples were collected, but usually only claws, skin, and whiskers. The ice seals decomposed rapidly with the abnormally high temperatures in northern Alaska.
What are the findings in stranded seals?
Many stranded seals exhibited bony protuberances, with very low fat thickness, indicating possible emaciation.
What is causing this UME? Are the seals running out of food?
There are many thoughts about the ice free Bering and Chukchi seas. However, at this point, we do not know the actual cause of the ice seal strandings. All age classes have been reported, and a subset of seals have been sampled for genetics and harmful algal bloom exposure. A few have had histopathology collected. Results are pending. As part of the UME process an investigative team will be established to work to try to determine the cause of this UME.
What impact did the abnormally high temperatures have on these species of ice seals?
It is possible the significant decreases in springtime ice extent in 2018 and 2019 forced a temporary northward shift in the distribution of these seals for pupping, nursing, molting, and possibly breeding. Ice-associated seals require sea ice for these important, and energetically demanding, life-history events. NOAA is also investigating whether animals were exposed to harmful algal blooms.
Is this UME caused by climate change?
We don’t know. It is difficult or impossible to manipulate variables in widespread wild populations, making the establishment of cause and effect relationships highly unlikely. Nevertheless, these ice seals do depend upon the presence of sea ice to complete their life cycles. Climate change is markedly reducing the areal extent and volume of sea ice.
Has this happened before? Is this related to the UME for ice seals in Alaska from 2011–2016?
There was an Unusual Mortality Event involving ice seals from 2011 to 2016, which was most active in 2011–2012. The minimum estimate for the total number of affected animals was 657 seals, including 233 dead stranded seals, 179 atypical subsistence harvested seals, and 245 live seals that stranded and/or were sampled during the permitted health assessments. The UME investigation determined that some of the clinical signs were due to an abnormal molt, but a definitive cause for the UME was never determined. The number of stranded ice seals in 2018–2019, and their physical characteristics, is not at all similar to the 2011–2016 UME. The seals in 2018–2019 are not exhibiting hair loss or skin lesions, which were a primary finding in the 2011-2016 UME.
What does the stranding of so many ice seals mean for the western Alaska coastal communities, where many people depend on marine mammals for food?
Marine mammal strandings have implications to marine mammal health and food safety. Therefore, they are a major concern to Alaska Native hunters and local communities. The local communities provided the necessary support to collect information that should improve our understanding on what is happening to the ice seals. We hope they will continue to assist us if seals continue to strand.
What are the next steps in the investigation now that an UME has been declared?
As part of the Unusual Mortality Event investigation process, an independent team of scientists (investigative team) is being assembled. They will coordinate with the Working Group and other scientific colleagues to review the data collected and to determine potential next steps. The investigative team will also coordinate its investigation with other on-going Unusual Mortality Event investigations. The investigation may require months, or even years, of data collection, analysis, and interpretation.
What additional resources are now available to pursue the investigation, since an UME has been declared?
A UME declaration provides additional expertise from the Working Group and additional stranding response partners. It also provides access to some additional funding through the Marine Mammal UME Contingency Fund. Finally, through the UME process all findings and interpretations undergo national and international scientific review.
Will you be collecting additional biological and environmental information?
The Stranding Network will continue to collect and analyze samples as needed to evaluate the situation regarding stranded seals. The Working Group will decide whether additional information is needed.
When will you have some results to share?
The Investigative Team will begin developing an investigative plan soon. You can track the progress of our investigation from our main UME webpage.
What is the risk to humans?
It is not known if there is any risk to human health through contact. Despite considerable contact by hunters and field personnel with seal carcasses, no known related human illness has been reported. However, because marine mammals and humans can share diseases, please stay away from marine mammals that are acting strangely or are dead. Immediately report these cases to the Alaska Marine Mammal Stranding Hotline at (877) 925-7773, or your local wildlife authorities.
Are there any risks to pets?
Pets should always be kept away from marine mammals, particularly diseased or dead marine mammals.
Where can I find additional information on ice seals and other Unusual Mortality Events?
What can I do to help the investigation?
The most important action someone can take is to report immediately a dead, injured, or stranded marine mammal by calling NOAA’s Alaska Marine Mammal Stranding Network at (877) 925-7773; or contacting local wildlife authorities at the following numbers:
North Slope Borough: North Slope Borough Department of Wildlife Management: 907-852-0350.
Bering Strait region:
- Alaska Sea Grant Marine Advisory Program: (855) 443-2397 / 907-434-1149.
- Eskimo Walrus Commission: (877) 277-4392
- Kawerak, Inc: (907) 443-4265.
Yukon-Kuskokwim delta: Alaska Sea Grant Marine Advisory Program: (855) 443-2397 / (907) 434-1149.
What is the Marine Mammal UME Contingency Fund?
The MMPA establishes the Marine Mammal Unusual Mortality Event Fund describing its purposes and how the public can donate to the fund. According to the MMPA, the fund: “shall be available only for use by the Secretary of Commerce, in consultation with the Secretary of the Interior:
- To compensate persons for special 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.
- For reimbursing any stranding network participant for costs incurred in preparing and transporting tissues collected with respect to an unusual mortality event for the Tissue Bank.
- For care and maintenance of marine mammal 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.