Within the varying nature’s characteristics is a comfortable home for any creature known to man. Be it the grass savannah, tropical areas, ice glaciers, and the like. Notably, the world’s largest land animal and carnivore, the male polar bear, can reach two to three meters in length and have a weight of between 300 to 800 kilograms (Crockford, 2022). Polar bears are considered top predators of sea ice extent with typical bodies, and as such, they are susceptible to changes in pack ice extent and composition brought on by global warming and its effects on their seal food. Most polar bears live in the seas and oceans.
While their bodies are alike, they differ from other bears in that their heads are considerably narrower and they have extended necks. Their pelage (fur) is typically off-white, but because of oxidation, it frequently appears more yellow throughout the summer and occasionally might appear brown or gray. Polar bears have light-colored fur, but their skin is black. Their large forepaws make great paddles for swimming in the ocean. Their forepaws and hind paws each have fur-lined soles that act as insulation and improve traction in snow and ice. Polar bears live 25 to 30 years on average. Polar bears are known to be compatible on the land as they are in the water and are agile in both environments. The main prey species of polar bears have ringed seals and, to a lesser extent, bearded seals. Ideally, the ringed seals uphold their breathing holes that range from freeze-up in the fall to break-up in the spring. Moreover, these animals can be found on unreceptive and coastal park ice areas where they prey on the ringed and bearded seals as well as walrus, whales, birds, and fish.
Historically, polar bears are thought to have originated from brown bears, also known as Grizzly bears, around 1.3 million years ago. These species are capable of interbreeding in zoos, as the young are fertile. Polar bears live in the Arctic region and depend on ice for survival. They grow up to 1.6 meters in height, have thick white fur, and can weigh about 410-720 kilograms. They have broad feet with soles that facilitate their movement across the ice by preventing them from slipping and insulating them from injury (Laidre et al., 2022). Over the past years, scientists have shown concern over the survival of the animal they depend on seals for food, but the ice melts have posed a great danger to catching prey. In addition, others have raised issues on the loss of genetic diversity due to inbreeding caused by restricted movement caused by large areas of melted ice. As a result, environmentalists have insisted on listing them as endangered species and demanded that the US write policies protecting them against extinction (Troutman Sanders LLP, 2008). The survival of the polar bears depends on mitigating problems that cause climatic changes, which in turn lead to the loss of their homes, mates, and food.
Polar bears represent the most ice-dependent animals in the Arctic. Research has shown that the world is experiencing global warming, causing ice to melt in the cooler parts. As a result, animals like bears who depend on ice to hunt seals, get mates, or search for new habitats are experiencing problems moving in fragmented ice. As a result, the animals converge in the cooler areas as a survival tactic to protect themselves from starvation. However, the survival strategy poses a considerable problem to the genetic diversity of the majestic animals (Maduna et al., 2021). It leads to inbreeding during the mating season, thereby losing genetic diversity, a vital survival mechanism in the animal kingdom.
Genetic Diversity
Maduna (2021), conducted a study on Ursus maritimus, also called the polar bears, across two decades to analyze the genetic variation with time. They realized that there was a three to ten percent genetic diversity loss for the six hundred and twenty-six bears they studied, with a two hundred percent increase in genetic differentiation across the regions. They concluded that the climatic changes that have caused the melting of sea ice have had a negative consequence on the survival of polar bears. Maduna explains that loss of ice has caused habitat fragmentation and loss of some of their homes, thereby leading to inbreeding. The polar bears depend on ice habitats for movement, reproduction, and foraging. Therefore, they cannot move to new grounds to hunt for food or meet new mates when the ice melts. As a result, they will reproduce amongst themselves, leading to a loss of genetic diversity. The authors advise consistency in genetic monitoring to develop adaptive management strategies for ice-dependent species.
The researchers’ study seeks to analyze the genetic diversity of polar bears and discuss whether fragmentation due to climatic changes have affected gene distribution. Maduna (2021) uses polar bears from the Barents Sea that Svalbard Archipelago captured from 1995 to 2016 as their samples. Later, they collect the total genomic Deoxyribonucleic Acid (DNA) and study their genotypes. The scholars argue that sea ice has been influential in the type of polar bears and their movements. Svalbard areas have many local polar bears during winter and spring, but pelagic bears may be present. However, ice fragmentation has caused a reduction in the number and time of pelagic bears around the sea. Maduna (2021), argues that the loss of ice during spring, which is the mating season, reduces mating opportunities for pelagic bears to local bears, thereby causing an in breeding. Ice melt has caused a significant loss of genetic diversity over the last two decades and may continue to worsen as the world keeps experiencing warm springs.
Climate Change
Greenland bears’ adaptations give hope to the species’ extended survival. Scientists say that the bears have changed their hunting pattern to feed after 100-180 days for survival. The report says that the bears may face extinction since the climatic changes have caused the ice to melt, which is essential for their survival (Laidra, 2022). The bears depend on the ice as launch points when hunting for seals. However, when there are ice fragmentations and a large area with no ice cover, the polar bears risk starvation. Laidre (2022) mentions that their co-authors studied some polar bears in the sub-arctic zones of Greenland, which are now isolated from their Arctic cousins in North Greenland. The authors say that some bears live in one fjord for years, which is contrary to those that live in the north that can travel about twenty-five miles in a few days. They have also adapted to eating after three to four months which increases their survival rate in the future.
The article discusses the issue of climatic change and its effects on polar bears. The ice-dependent animals suffer from a lack of food and mating partners due to ice fragmentation. The catastrophe restricts their movements as they cannot swim on open water for long distances and are not skilled in hunting the elusive seals inside the sea. However, some polar bears living in Greenland have adapted to living in one fjord for many years as opposed to their cousins in the northern arctic, who roam for several miles in a few days (Laidre et al., 2022). In addition, they can go for approximately one hundred to one hundred and eight days without food, an important survival tactic that will secure their existence in the future.
Polar Bears under the Endangered Species Act
Troutman Sanders mentions that the US Department of Interior (DOI) accepted the US Fish and Wildlife Services (FWS) proposal to list the polar bears as threatened under the Endangered Species Act (ESA) due to the impacts of climatic changes. The FWS proposed the polar bear listing in January 2007 over concerns that climatic changes have immensely affected their Alaskan habitat. Troutman Sanders says that several studies reveal a possibility of a ninety-seven percent loss of the September ice by the end of a century, which may lead to polar bear extinction in the US within the next forty-five years. And since it has been a decade and a half since the proposal took effect, drastic measures have been witnessed in favor of polar bears. The author mentions that listing the polar bears under endangered species will impose regulations that will reduce further loss of the species. However, other interest groups have been keen on terming the endangered animals to avoid using the ESA to impend future energy acts in affected countries.
The article, Troutman Sanders discusses how the national governments are ready to protect animals from extinction. Global warming has been a major contributor to climatic changes worldwide. Scholars have mentioned the release of Green House Gasses (GHG) as a significant contributing factor to climate change. As a result, many environmentalists have risen against energy companies that accelerate GHG released in the air and have demanded the country make policies that control their release.
Polar Bear Populations and Climatic Threat
Ideally, sea ice is known to be essential habitat for polar bears whereby they use the ice to travel, hunt, mate, and den. However, based on the research, as the polar bear melts across the Arctic due to climatic change, more female polar bears emanating from the Southern Beaufort Sea are making their maternal dens on land rather than the ice. According to Stirling (2009), polar bears are less abundant in regions of extensive multi-year ice and the immediate locale of polynyas, especially due to the density of ringed seals, which is lower in such areas. With the climatic change and ice becoming unstable, the population of bears that den on the seas and oceans has been declining tremendously. Additionally, adding to the pressure on the climatic crisis, one of the justifications given by the Fish and Wildlife Service to its failure to do proper assessments on the impacts of oil and gas projects on polar bears is based on the uncertainty of how these species will respond and survive to the climatic change.
Behavior and Psychological Aspects of Polar Bears
Polar bears with continuous access to ocean ice continue to hunt throughout. Ideally, the hunting approaches of polar bears and success rates are based on the seasonal variations in different regions (Crockford, 2022). Furthermore, the most common hunting approach as applied by the polar bears is lying beside a breathing hole, then waiting for a seal to surface and breath. Contrary to the most common myth, polar bears never cover their noses with paws when aggravating. Additionally, they do keep their heads low while slowly and solidly. Finally, it is worth mentioning that the largest population of polar bears’ annual caloric uptake for the year usually occurs during the spring and early summer seasons, whereby newly weaned ring pups are approximately 50% fat through wet weight (Crockford, 2022). Superlatively, the specific ocean ice habitats that the polar bears in the spring seasons hunt are considered stable with profound snowdrifts across pressure ridges that are charming for ringed seal birth and breathing holes.
Additionally, polar bears are known to prey on harp and hooded seals where they are present and intermittently on walruses. Moreover, these animal species have a remarkable capacity to store and maintain many fats during preying, seals, which are present then fats for extended seasons when there is no food (Crockford, 2022). The polar bears’ metabolism automatically slows down into a hibernation mode when food is unavailable. On such occasions, the energy consumed is extremely low and is based on a lower rate.
Interactions with Human Beings
Undisputedly, polar bears are considered essential to the culture and economy of regional people in various regions. Moreover, offshore development and the production of hydrocarbons can affect polar bears negatively. Remarkably, most of the anthropogenic contaminants in the Arctic marine ecosystem environments are regarded as bioaccumulated as they progress with the food chain. With the polar bear being at the top of the ecological pyramid and living principally on fats, they can achieve a prominent level of contaminants loading in some areas. In addition, polar bears only live where it is cold around the Arctic region, though they have been able to adapt to the warmer climate (Crockford, 2022). It is unclear whether such contaminants are sustainable in interfering with the reproductive functionalities or the immune system.
Based on the recent past, ecotourism in viewing the polar bears in a few regions has increased gradually, with positive economic benefits and a considerable rise in worldwide appreciation of the polar bears. The conservation of polar bears and their specific habitats are agreed upon by a unique agreement signed by different countries with polar bears (Taylor & Lee, 1995). Population research has continued in several regions by ensuring that such populations are harnessed based on sustainable levels. Hence, the survival of the polar bears is not threatened by legal hunting; however, this needs to be regulated and controlled carefully since they have a low reproductive capacity and would require several years to recover from overharvesting. In some areas, long-term studies have shown that climatic warming can cause the ice to break up earlier, which is related to the decreasing population size in different areas (Vongraven et al., 2013). Ideally, based on the respective models of the progressively increasing temperatures in the Arctic, because of increased concentrations of emitting greenhouses gases, the current observations based on the satellite data and climatic projection models and techniques show a prediction of a continuous and significant decrease in the total amount ocean, the amount of ocean ice and rise in ocean water soon.
Conclusion
In conclusion, polar bears are considered one of the largest species of bears found globally and are completely white. Ideally, these animal species have a noteworthy capacity of storing and maintaining a large substantial amount of fats during the periods of preying, seals, which are present then fats for extended seasons when there is no adequate food or none. Additionally, with the polar bear being at the top of the ecological pyramid and since they live on fats, they can achieve an elevated level of contaminants emanating from a couple of areas. Lastly, the survival of the polar bears is not threatened by legal hunting; nevertheless, this needs to be regulated prudently because they are known to have low reproductive ability and would require many years to recover from overharvesting.
Climatic changes are causing the ice in the Arctic to melt, thereby leading to habitat loss for the polar bears. The government should work with conservation institutes to ensure they control adverse climatic changes by making policies monitoring GHG release and protecting the animal from extinction.
Polar Bear Photos
References
Crockford, S. J., 2022. The State of the Polar Bear 2021. World Warming Coverage Basis Notice, pp. 29.
Laidre, K. L., Supple, M. A., Born, E. W., Regehr, E. V., Wiig, Ø., Ugarte, F., Aars, J., Dietz, R., Sonne, C., Hegelund, P., Isaksen, C., Akse, G. B., Cohen, B., Stern, H. L., Moon, T., Vollmers, C., Corbett-Detig, R., Paetkau, D., & Shapiro, B., 2022. Glacial ice supports a distinct and undocumented polar bear subpopulation persisting in late 21st-century sea-ice conditions. Science, 376(6599), pp. 1333–1338. Web.
Maduna, S., Aars, J., Fløystad, I., Klütsch, C., Zeyl Fiskebeck, E., & Wiig, Ø. et al., 2021. Sea ice reduction drives genetic differentiation among the Barents Sea polar bears. Proceedings Of the Royal Society B: Biological Sciences, pp. 288(1958), 20211741.
Polar Bear World. (n.d). Polar Bear Predators.
Stirling, I. 2009. Polar bear: Ursus maritimus. In Encyclopedia of marine mammals. Science Direct, pp. 888-890.
Taylor, M., & Lee, J., 1995. Distribution and abundance of Canadian polar bear populations: a management perspective. The Arctic, pp. 147-154
Troutman Sanders LLP., 2008. Polar Bear Listed as “Threatened” under the Endangered Species Act. Venulex Legal Summaries. 2008 Q2, Special section p1-2. 2p.
Vongraven, D., Aars, J., Amstrup, S., Atkinson, S. N., Belikov, S., Born, E. W., & Wiig, Ø., 2012. A circumpolar monitoring framework for polar bears. Ursus, 23(sp2), pp. 1-66.