Ringed Seal (Phoca hispida) And The Shrinking Arctic Sea Ice

It is now a common belief that global warming is the main cause for the melting of the sea ice of our planet Earth. The Arctic Sea ice is no exception. Evidences of scientific exploration and research with the aid of satellite technology reveal that the Arctic sea ice is continuously shrinking.

ABSTRACT

It is now a common belief that global warming is the main cause for the melting of the sea ice of our planet Earth. The Arctic Sea ice is no exception. Evidences of scientific exploration and research with the aid of satellite technology reveal that the Arctic sea ice is continuously shrinking. Our study aims to answer some specific questions related to the shrinking of the Arctic Sea ice, its current trend, what researchers project for the future trend and its impact on the ringed seal in particular. Scientific studies show that the Arctic sea ice extent significantly reduced from 1950 to 2010 from about 13 square km to 11 sq km (Fig 3). This melting is related to sea level rise which shows a linear rate of 3.17+/-o.4 mm/yr from 1993 to 2013(Fig 1B). Such observations come along with the threatened species that depend on the icy world, the ringed seal being one of them. Ice- loving ringed seal have started to experience loss of habitat. Apparent proof is the destruction of their ice caves which allow them to escape from their prey and most important are the vulnerable conditions of their pups during breeding season. As a response, the federal government has listed the ringed seal in the endangered species act. Other geo-engineering alternatives to save the sea ice are being proposed by scientists and analysts to block heat sources and carbon dioxide emissions and other causes of global warming (Wadhams, 2012).

Introduction

The flood that happened in our village (Kotlik, Alaska) on November 11, 2013, caused serious damages to the ground structures and buildings due to the chunks of sea ice that rushed landward from the Bering Sea. Houses were swept from foundations, water and sewer systems were destroyed, power blacked out, pets were lost and the community was evacuated to the school building. Normal operations halted. The aftermath revealed the impact of one of the threatening phenomena of our times – the dislocations of the components of a given habitat due to the consequences of environmental change include the melted and fragmented sea ice. Being in the north polar region, we are concerned with the Arctic sea ice. The sea ice insulates the ocean below it, prevents heat and moisture from moving into the atmosphere, and reflects incoming solar energy coming to our planet Earth. Seven percent of our planet’s oceans is covered with sea ice. Now, based on satellite images the Arctic sea ice is showing alarming changes that are believed to be a result of global warming. Some specialists project it is possible that the Arctic may be completely free of sea ice in the very near future. With this situation, the creatures that depend on the ice and their sympagic (ice specific) food web are at risk. Within the sea ice itself are algae, fungus, bacteria and viruses. Melting ice releases organisms and nutrients into the water below providing an energy source for the polar food chain. Below the sea ice are communities of zooplankton that feed on the sea ice algae. Fish, squid, and sea mammals feed on these zooplankton. Seals are among the sea mammals that rely on the sea ice food chain to survive. We then aim to study the effect of this diminishing sea ice on one species of these creatures, the ringed seals.

Objectives of the Study

Our study focuses on the impact of shrinking Arctic sea ice on seal survival, specifically the ringed seals of Alaska. There are 5 questions that we aim to answer. First, what is the trend of sea ice extent from 1950 and beyond? Second, how do these changes affect the survival of ringed seals in Alaska? Third, what are the threats to their survival? Fourth, What are the implications of these threats? Finally, what alternatives are possible to protect the ringed seals and to possibly reverse the trend of shrinking Arctic Sea ice?

Figure 1A. Global heat distribution Figure 1B. Mean Sea Level Rising Trend

Figure 1. When scientists add up all of the heat warming the oceans, land, and atmosphere and melting the ice, they calculate that our planet is accumulating heat at a rate of 2.5×1014 watts since 1998 which to some alarmists would equate to 4 Hiroshima bombs per second. (Cook and Lacatena, 2012)

This melting is related to sea level rise which shows a linear rate of 3.17+/-o.4 mm/yr from 1993 to 2013 (Fig 1B).

The Arctic Sea Ice: Now and the Future

The Arctic is a polar region located at the northernmost part of the Earth. It consists of the Arctic Ocean and parts of Alaska, Canada, Finland, Greenland, Iceland, Norway, Russia, and Sweden. (Figure 2) http://n.wikipedia.org/wiki/Arctic

Figure 2: The Arctic Figure 3: The Arctic Sea Ice Shrinking, 1950 -2010

Surrounded by land, at one end of the globe (North Pole), the Arctic receives no sunlight a part of the year, while for another part it receives daylight at times for 24 hours a day. Since 1979, scientists have been using satellites to track the ice extent, which is erratically but systematically shrinking (Figure 3). Before 1979 tide gauges were used. Satellite radar altimetry and satellite laser altimetry find that Arctic sea ice has also been thinning. Arctic sea ice extent significantly reduced from 1950 to 2010 from about 13 square km to 11 sq km (Fig 3). The Arctic is expected to have a completely ice- free summer within this century. This means that each winter the ice is not re-freezing to the winter extent of the previous winter. Year after year, the Arctic is losing ice mass. According to Dudley Robinson of Ireland, researchers were astounded when, in the fall of 2007, they discovered that the year-round ice pack in the Arctic Ocean had lost some 20 percent of its mass in just two years, lower since satellite imagery of1978. Some scientists believe that, at that rate, the Arctic could be gone by as early as 2030.

Figure 4. “Arctic sea ice has receded dramatically faster than the mean of IPCC models projected, reaching levels not expected until 2065.” (Ramez, 2012)

The graph shows dramatic shrinking Arctic Sea ice in both projections.

The Biology of Seals

There are at least six types of seals in the Arctic. They are the spotted seals, harp seals, bearded seals, hooded seals, ringed seals, and ribbon seals. The melting of the arctic sea ice has endangered the habitat of those that live near the outer reaches of the ice. Efforts to save these beautiful animals are underway, and public awareness is key in the struggle.

Bearded Seal

Ringed Seal

Ribbon Seal

Spotted Seal

Hooded Seal

Harp Seal

Figure 5. The six types of seals of Alaska

The spotted seals are like other predators and any other seals that that inhabit the ice. They use ice for for feeding, resting, and pupping. These types of seals are the smart ones that dive in water for a while. He spotted seals are larger than the bearded and ribbon seals. They are seen seen around the Bering Sea. Harp seals usually swim around the cold Arctic waters and they eat fish and crustaceans. Not like bearded seals they move to the south to the warmer waters. Harp seals are bigger then spotted seals, and they are smaller then the bearded seals. The harp seals are polar bears favorite prey because the seal is fluffy with white fur of the young. But the Alaska Eskimo’s always hunt bearded seals for meat, oil, and hides. Hooded seals are migratory species that have been mostly found far south as the Caribbean. Their name refers to the elastic sac that extends from their noses to their forehead. It seems like they are hardly found in Alaska, but they are hunted for pelts. Ribbon seals are the most unusual of the Arctic seals. It’s very easy to identify them.

The adult seal has four different identifying features. One of them is that one ribbon encircles their neck, one encircles their posterior, and two encircle their fore- flippers. They are beautiful. These seals are also used for fancy outdoor clothing.

Ringed seals are migratory and live wherever they find sea ice. They are the smallest seals weighing up to 150 pounds, and are about five feet in length. The beautiful ones are the most common in the Arctic, and they are very important to the Alaskan economy. For the coastal Eskimos they provide food, and consumable products. There are more than 250,00 ringed seals in the Arctic area. Polar bears, killer whales, and walruses also all prey on ringed seals. (Anders, www.eHow.com )

The Seal Life Cycle

In a seal’s life cycle begins with breeding. During this time the hormone levels of a male seals change. They tend to become more protective of their mate, and aggressive. With the females they develop a fluid-filled sack containing an egg. A successful female mates the biggest and strongest male. The breeding season, which may last for several weeks, is one long, continuous battle to keep other males away. Common seal mating takes place in the water, and it is hard to see how many times a female is mated. All seals have to molt their old fur each year. When their hormones change the seal go to the molting grounds. During this time the grey seals gather in a large noisy group. The ones that usually molt first are the juvenile, followed by the females. This molting season usually takes as long as six weeks to complete. After that their new hair is grown and they go to the sea to resume feeing.

During the pupping season the fetus grows for about nine months, and this event the female returns to the breeding grounds. When the baby arrives, they look for a place to stay. The pup will be long and spindle-shaped and breech births are common during that time. When the pup is born, the female sniffs it and calls it. They call it the mother bond, learning each other’s smell and voices within a few minutes of the birth. The pups are helpless and rely on their mother’s milk for the first few weeks. During this time the pups grow very quickly and they have a thick layer of blubber that will help them with the water. But the seals are different. They also can swim with their mothers just for a few hours, and this will become an adaptation to avoid dangerous predators. This happens because it helps them to be 7 away from their mothers. Not all pups survive after they are born. Some get lost before they learn to smell and call. If the mother doesn’t notice which one her pup is, she will not suckle them. Females can become pregnant when they are young or when they are three or four, and deliver the pup a year later. Some of the mothers can have twins, but it makes it difficult for them because the mother may not have enough milk. After she becomes pregnant, the mother gets mated at the breeding site. After that she hauls out, and sheds her a new coat and its ready. When the male is six years of age the male seal is more mature. When seals are 10 years of age that’s when they are able to fight and attack. But, when they are six or seven that’s when they are strong enough to mate. But once mating season is over males molt few weeks later, and females haul out to rest between fishing forays.

If the pups survive during pup season, then these seals are long-lived animals. Both of the seals often live longer then 30 years, and female grey seals live until up to 46 years. It is hard to find out because they tend to die in the sea. Pollution, and the drowning in fishing nets are some of the main causes.

The Alaska Ringed Seal

Out of all the seals in Alaska the ringed seals are the smallest. These small creatures make a hole with their claws in the ice, and live under the water. For the females they make snow caves with holes so they can rest and give birth. Males tend to get a strong smell that smells like gas, and their faces turn black in breeding season. Among the general population, the ringed seals get most preyed on. Almost every two to six days polar bears kill them. Pups are prey for polar bears, arctic foxes, red 9 foxes, and ravens. Arctic Foxes and polar bears can locate seal snow caves by smell. Females give birth to a single pup within a snow covered birth lair. Pups are born covered in a coat of white wooly hair that covers them until they can build fat. The cover sheds at 2 to 3 weeks. The average weight of pups at birth is 10 pounds Females nurse their pups for about two months and during that time the pup doubles its birth weight. Weaning usually takes place at ice breakup. Most females breed again within a month after giving birth. Most female ringed seals first ovulate at 5–6 years of age and first give birth at 6–8 years. Males become sexually mature at the same age. Breeding season takes place in April to May. During this period the males begin their aggressive behavior and have a strong scent from their faces. Polar bears also avoid male ringed seals at this time of year. ( Burke, 2012)

Threats to Ringed Seal Survival

The climate changes endanger the survival of seals in general and the ringed seal in particular. Dramatic climate change models predict that the continuing sea ice decline may soon lead to harsh conditions to support seals. Ringed seals come ashore, depending almost exclusively on sea ice for their reproduction and lives. These are conditions that limit hunting of seals by Alaska natives for subsistence and handicraft purposes. Ringed seals are also threatened by reduced snowfall. Their pups are born and spend the first few weeks of life in snow dens, which protect them from predators and freezing. The decreased snowfall, earlier snow melts, and winter rains are pushing more pups out of their shelters before they are able to survive in the open.

An additional challenge is that ringed seals have only one pup per year, making them especially vulnerable to environmental changes.

Figure 6. Hundreds of seal pups were washed up on the shore of Prince Edward Island in 2011 due to warmer winter climate. The image above is a young seal suffering from lack of ice cover.

As shown in the graph in Figure 3, the Arctic sea ice continues to shrink in this century, more than two thirds is snow cover for ringed seals to reproduce. The ringed seal apparently builds caves on the sea ice to protect itself from a threatening situation. The sea ice will pile up and disappear as it melts, and the area where the seals raise their pups disappear. Ringed seals are threatened because of their dependence on sea ice; thus affecting their habitat. Changes in sea ice thickness, coverage, formation timing, and duration of coverage due to climate change may basically alter the quality and amount of sea ice and snow necessary for resting, molting, and pupping. Activities associated with offshore oil exploration and recovery could affect ringed seal 11 distribution and the prey they feed on. However, the effects of direct contact with oil on ringed seals have not been studied ( Cammen and Soulen, 2013).

Figure 7. Scanning the ice to avoid its predator, the polar bears, a ringed seal tries to get some air. Now, this seal’s biggest threat is not a predator but the changing climate.

Threatened ringed and bearded seal populations gain protection. The listing of the polar bear in 2008 has brought them into climate conditions. Mammals are having a more difficult time living because the sea ice is shrinking year by year. (Alaska Dispatch News, 2012).

Implications

The consequences of the loss of seals are attributed to global warming which causes the sea ice to melt, rising sea levels, then the seals are left not having the resources they need to survive. Seal pups are forced into the water before they are ready to fend for themselves. They need the ice platforms for nursing and resting. If they are cast away into the ocean water, then they are likely to be at risk for hypothermia, starvation, and being crushed by moving ice in the arctic. The sea level also impacts the seals by leaving them washed up on the shores. For example past experience of flooding in the Kotlik village on November 2013, chunks of sea ice came in from the Bering Sea. The sea level rose causing a flood that affected the ground’s structure. And we also believe that these floods affect the seal’s survival. Although these issues 12 may seem out of our control, there are issues/problems that can be resolved. Such as keeping an eye out for the species that are endangered. It can be a program such as the National Oceanic and Atmospheric Administration (NOAA) that has decided to list bearded seals and ringed seals under the Endangered Species Act. The NOAA move is taken to prevent importation to the U.S from other countries of those seals or their parts. In the future, 100 years from now scientist believe that climate change might affect the species in Alaska. Another problem that has been listed is what the ocean contains, from animals, to oil spills, and waste. The killer whales mainly target stranded baby seals on icebergs, and polar bears target the seals when they swim up to the ice’s surface, where they previously made a breathing hole. Also the polar bear pounds the ice and stays on guard waiting for the seal to pop up. Obviously there is not much we can do about this, because the need of other arctic animals is also important. But in certain cases if the baby seals weren’t left astray they could have had the chance to survive. Things that we as people can control however can help the seals survive. That means preventing oil spills, and not being careless about the waste that goes into the ocean. There has already been a major event that took place on March 24, 1989. And that is the Exxon-Valdez oil spill that had long lasting affects on Alaska’s environment, animals, and way of life. The harbor seal was just one species drastically affected by the tragic oil spill of 1989. Even after two decades, in 2007-the National Oceanic and Atmospheric Administration reported that 21,000 gallons of crude oil still pollutes the ecosystem within a 450-mile radius-and the oil continues to kill animals within its sphere. Hazardous waste is also something that needs to be discussed. Because Greenland, for example has plastic bags, fishing nets, barbed wire, fuel tanks and beer bottles that are found washed up on shores seldom visited by humans. Also on Alaska’s Seward Peninsula local people have discovered corroding aircraft batteries in rivers which provide drinking water for summer fishing camps, vehicles dumped by the United States military, and canisters of mustard gas half buried in the tundra. This is very toxic for the environment, and the people/living species. Some scientists have also voiced that people who hunt seals should cut down on hunting them. Although 13 this is an option, we believe if people would prevent the damage being done to the ocean, we wouldn’t have to worry about loosing one of our subsistence foods here in Alaska, the ringed seals. Focusing on the implications of something that affects the ocean/climate, animals, and people can give us awareness of what should be done.

Some Alternatives To Save The Arctic Sea Ice

So we ask: Are there things that can be done to reverse the complicated processes that are believed to be causing the Arctic sea ice to melt. We thank the creative human minds that invented high technology such as the satellites to detect what is happening on our planet Earth. This invention plus the work of scientists, researchers and concerned citizens has made us aware of the threats to the organisms that live on this planet. The case of the ring seal is not an isolated case.

What affects it affects all the other species of the ice ecosystem where they dwell, including the human species. There is no single solution but here are some programs and thoughts.

A support to the National Marine Fisheries Services (NMFS) proposal to designate critical habitat for the Arctic species ringed seal (Phoca hispida) under the Endangered Species Act (ESA) is a great move because it is soliciting the comments on all aspects to strengthen the proposal- economic, national security, and other relevant implications. The specific area of marine habitat it designates is in the northern Bering, Chukchi, and Beaufort seas. Other ways are continuing professional researches and related programs to update the status of sea ice extent and volume, supporting conservation movements, like the Ocean Conservancy, and since the melting of sea ice is already happening, it is just practical to assure safety by designing engineering works or responses to demands for search and rescue systems, coastal and inland stations for supply and people transfer. Dr. Peter Wadhams (2012), Ocean Physics Professor and Head of Polar Ocean Physics Group, University of Cambridge, said that geo-engineering may be our best chance to save the sea ice left. Wadhams refers to techniques to artificially lower surface temperatures by blocking the sun. One proposal he mentions is “whitening” low-level clouds by injecting fine sprays of water into them. Another involves releasing solid sulfates into the atmosphere from balloons to cause formation of radiation-reflecting aerosols. He mentions that a simpler step would be to paint roofs and pavements white, such measures as sticking-plaster solutions. Applications should be continuous, otherwise any gap would bring warming back at an accelerated rate. But further questions would need more time and expertise for research and modelling. Wadham further asks: Is there a geo- engineering technique that would cool the entire planet? Is there a way to cool only the Arctic in summer, to keep sea ice from disappearing? What effect would cloud whitening or chemical release over the Arctic have on precipitation patterns and on temperature? Wadham’s questions are challenges that need to be addressed with urgency.

References

  1. Arctic Sea Ice, SEARCH 2014 Sea Ice Outlook: August report Reven1.typepad.com/blog/predictions
  2. Cryoshere Science Research Portal by J.C Comiso, C.L. Parkinson, T. Markus, D.J Cavalieri and R.Gersten 11/29/2014 Neptunegsfc.nasa.gov/csb/index.Php?Section=23415
  3. Shrinking snow depth on Arctic sea ice threatens ringed seal habitat by Nancy Gohring, September 17, 2012 www.Washington.edm/news/2012/09/17/shrinking -snow-depth-on- arctic-sea-ice-threats-ringed-seal-habitat/
  4. How much will sea levels rise in the 21st century? –IPCC Projections http://www.Skepticalscience.com/sea-level-riselpredictions.htm
  5. Arctic Sea Ice Shrinks to Record Low by Terrell Johnson Published Nov 17, 2014, Weather.com
  6. Seals-The seal’s life cycle www.snh.org.uk/publicans/online/naturally scottish/seal/
  7. Types of Arctic Seals by Valerie Anders, ehow contributor ehow.com Seals in the Marine Ecosystem-WORKING TO END THE CANADIAN HARP SEAL SLAUGHTER.ORG
  8. Threatened bearded and ringed seal populations gain protection (Alaska Dispatch News by Jill Burke December 21, 2012 Jill (at) alaskadispatch.com
  9. GLOBAL WARMING AT HIROSHIMA ATOMIC BOMBS PER SECOND www.4hiroshimas.com
  10. Ice-Loving seals and the Loss of Sea Ice, by K. Cammen and B. Soulen Ocean.si.edu/blog/ice-loving-seals-and-loss-sea-ice
  11. National Snow and Ice Data Center, November 4, 2014, Nsidc.org
  12. Coast Guard, EPA Agree to Analyze How Oil Spill Clean Ups May Affect Endangered Species of Hudson River, The Center of Biological Diversity/Mollie Matteson, December 1, 2014 www.biologicaldiversity.org/news/press_releases/2014/crude-oil- transport-12-01-2014.html
  13. Largest Critical Habitat Designated in History Would Protect 226 Million Acres of Alaska’s Ringed Seals By The Center of Biological Diversity/Shaye Wolf December 2, 2014 www.biologicaldiversity.org/news/press_releases /2014/ringed-seal-12-02-2014.html
  14. NOAA proposes vast marine area as critical habitat for ringed seals by Yereth Rosen, December 2, 2014 www.Adn.com/arcticle/2014 1202/ noaa-proposes-vast-marine-area- critical-habitat-ringed-seals
  15. Scientific American Volume 307, Issue 6, 2012 http://www.scientificamerican.com/article/geoengineering- last-chance-save-sea-
  16. http://www.damtp.cam.ac.uk/people/p.wadhams/

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Ringed Seal (Phoca hispida) And The Shrinking Arctic Sea Ice

It is now a common belief that global warming is the main cause for the melting of the sea ice of our planet Earth. The Arctic Sea ice is no exception. Evidences of scientific exploration and research with the aid of satellite technology reveal that the Arctic sea ice is continuously shrinking.

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