Climate ChangeEnvironment

The Climate Change Poster Child: A Science Review

Abstract

The last five years have been the hottest ever recorded in the 139 year history of the National Oceanic and Atmospheric Association (NOAA). The increasing trend comes from a massive surge in human industrialization around the globe, which is felt directly in the Arctic. For example, in recent years, there has been a dramatic decrease in the tundra’s ice levels. Now, in the Anthropocene era, arctic environmental shifts are occurring exponentially, faster than what has ever been recorded. This directly affects one arctic species in particular, the polar bear, which depends on a stable habitat to exhibit fundamental behaviors, like hunting and migrating. Human globalization has recently redirected its attention to the Arctic. A largely untapped cornucopia of natural resources, it has recently seen rapid industrialization, notably with oil drilling. The focus of scientists and governments has been predominantly on the effects of global warming in the Arctic, looking at the problem broadly. There is much research on the specifics of warming in the Arctic, and most of it is from the oil companies themselves. However, the current literature is widespread and focused on the larger Arctic, instead of the species populations within it. This is not an effective approach to minimizing the impact of oil drilling as it applies to one species in particular, the polar bear. Our current approaches are in fact further devastating and restraining the species.

Introduction

The Arctic is sustaining approximately 20,000 to 25,000 polar bears, with 19 subpopulations dispersed through the region [1]. Of these, approximately eight are seeing a decline. The analysis that climate warming would have a negative effect on sea ice gained popularity in the early 1990’s. It was recognized in a study of ice sensitivity that an increase in the mean temperature of just 1.0 degree C could advance ice breakup in the Hudson Bay region of Canada. This ice breakup becomes an ecological concern as polar bears are greatly dependent on ice to hunt the majority of their prey, mostly being ringed seals. The species fasts for an approximate 4 months out of the year, however, when sea ice becomes limited, polar bears fast for up to 6 months. This nutritional stress can have effects on body condition, as well as reproductive viability. A short free ice period (101 days) usually results in 96-99% survival, while a long free ice period (mean 135 days) usually gives a 73-79% survival rate [1]. For polar bears, this is a major threat, causing their populations to drastically decrease.

Drilling Concerns

Current oil drilling also adversely affects polar bear habitats. The ANWR (Arctic National Wildlife Refuge) is approximately 20 million acres of land that is set aside to be void of development. However, the U.S. government is opening the site up to drilling, which contains another host of environmental concerns for the Arctic and the polar bear. Oil drilling is a major contributor to ice break up, both from its contributions to global warming and from ships, whose routes break up ice [2], which will impact both habitat and dietary needs of polar bears.

Seismic Exploration

The habitat reduction of the 1002 area of the ANWR is 35 times more likely to pose a significant threat to the ten resident species inhabiting the area [3]. The exploration of the Arctic alone would remain detrimental to polar bear health. The primary method of oil exploration relies on 3-D seismic imaging and 4-D ground penetrating imaging, such as lidar. The imaging is obtained through exploration trips with ground and air resources, like vehicle convoys and planes.

The increased presence of humans is especially impactful to female polar bears in gestational periods. Female polar bears may leave the den area if it is disturbed, and the cubs will be left with no mother, and will die [4]. Oil companies have stated their efforts will mainly be through the winter as to minimize impact to the environment, however winter is when polar bears will den with their cubs, so the disruption will lead to den abandonment. There are regulations in place, saying exploration can only happen within 0.8km of a den to minimize exposure to the bears. However, because of the limited data, oil exploration teams have no idea where dens are located.

With both the oil excavation team’s presence and the forced displacement of the bears into Innuit villages, the human processing of the land will dramatically increase the frequency of human and polar bear interactions. Polar bear migration trends report the bears either moving farther north in search of more ice or south in search of human waste and whale carcasses from Inuit village. If the bears continue to move to these northern and southern tips where oil rigs are mostly located along the ANWR and Beaufort Sea, more bears will be killed.

What’s Already Been Spilt

The threat of an oil spill is concerning to ecologists and biologists. A 2013 BOEM (Bureau of Ocean Energy Management) analysis of oil spills in the North Slope region of the ANWR found 1,577 spills larger than 42 gallons, 10 spills larger than 21,00 gallons, and 2 spills larger than 42,000 gallons of oil. Other processed materials to run oil rigs, such as diesel, engine lube oil, gasoline, hydraulic oil are entering and altering the ecosystem. In 2017, 43,000 gallons of operational oil were spilled. In 2006, BP failed to prevent corrosivity on their oil pipes in the Prudo Bay region, which leaked 267,000 gallons of oil in the region [5].

The Environmental Protection Agency has recently published research addressing smaller scaled spills. This research showed that if the oil penetrates six to ten inches of soil, hydrocarbon eating microbes can generally remove the oil. However, for large spills there is little we can do. Shell oil company says they have a plan to clean up the oil spill in the Arctic that can get 95% of the spill up. But, in reference to Deepwater Horizon, which had a massive clean-up effort in an area where there were not icebergs everywhere, clean-up efforts only effectively cleaned 3% of the oil spilt. The U.S. coast guard has vigorously stated that the U.S. does not have the resources to clean any oil spill in the arctic, “zero spill response capability.” [3]. This shows the U.S.’s complete lack of accountability and capability in dealing with an oil spill.

As it applies to Polar Bears

If an oil spill did occur, the effects would be catastrophic. Oil is less dense than water, so most of it would float on the surface; however, swimming would become impossible for animals who mainly swim on the surface, like the polar bear. Aerosols are released when oil comes into contact with the air, which can make breathing difficult for many animals. In the Arctic, thermoregulation is also paramount to the survival of most animals there, but when oil covers an organism, it can make thermoregulation largely impossible [6]. The oil that would break down would turn into compounds that mix with the water, which would be detrimental to the fish and krill that survive in the arctic ecosystem. Krill are the primary consumer of the arctic food chain, which are then eaten by arctic cod, holding the secondary consumer position. Cod are eaten by a number of tertiary consumers, like the ringed seal and arctic fox, both of which are a part of the polar bears diet. Oil spills would mean catastrophic cut offs at the primary and secondary levels, who make up the fundamental predation in the ocean. It would mean devastation to seals and eventually would mean continued devastation to the polar bear. Yet, this research is still rather limited. Current knowledge about Arctic flora and fauna and their interactions is incredibly baseline and is not enough to actually reach a consensus on how this would specifically affect polar bears.

Dietary Strains

Similar to other species of carnivores, polar bears exhibit much higher RMR (resting metabolic rates) than many other terrestrial mammals, including other members of ursids. A study on captive male polar bears over six study sessions measured an average RMR value of 0.34 ml O2, with a post of absorptive or fasting value of 0.30 ml O2, which converts to 37.1 MJ/day. Based on the post absorptive RMR, the results were within 0.5-11.4% of previously reported subadult polar bears. While comparatively to other ursids it was 2-21% greater while resting or denning. The nutritional cost needs to satisfy energetic balance requirements of the species is rather high [7]. This caloric need is met with ringed seals, which are preferential in a polar bear diet due to their energy-dense blubber. This research shows a dramatic increase in what scientists previously thought was needed to sustain polar bears.

90% of the bears’ time is spent stalking, with 10% actually hunting. However, bears recently have displayed patterns of scavenging. Polar bears who scavenge on bowhead whale carcasses and previously killed seals have displayed no significant loss in mass. The foraging nature of the bear is becoming more predominant as the bear shifts to scavenging approach. Ultimately, the energy balance of the bear is controlled by the relationship of metabolizable energy versus the expenditure from the basal metabolism. This is dependent on various external and internal factors like thermoregulation, reproduction, and activity. This relationship is largely dependent on the activity of the bear. Bears who moved more (greater than 1.0 km/h) had 1.5 times greater FMR rate than those who moved less (less than 1.0 km/h). The activity caps are largely specific to individual bears in individual sub populations of the species. [7].

This research shows us that the dietary needs of bears are incredibly individualized, so much so, that entire activity behaviors can be different across different sub populations in the Arctic. Yet, we still have minuscule data on the actual location and numbers of bears in these populations. Current research isn’t enough to validate the oil companies claim that their effects will be limited on polar bear species. The further nutritional strain imposed from oil drilling in the Arctic would be devastating to the polar bear species.

Approaches

Scientists are currently trying to gather benchmark data for key species in the Arctic. This includes numbers on abundance of fish and their distribution, bird lime, marine mammals and apex predator needs, like the polar bear. However, there is a need for community driven observation, because current scientific measures of observation are not sufficient. We do not have a comprehensive view of the arctic landscape; we currently depend on satellite imaging to see what is happening in both the landscape and in polar bear populations, which doesn’t provide enough specific data. Right now, scientists cannot collar male polar bears because their shoulders are too big, and their necks are too narrow, so the collars slip off. As a result, the population of bears that are collared remains very small, and the lack of more broad data drastically limits our understanding of the effects on polar bears in the Arctic.

Governments are also stepping in to get more research. The EU funded a research project, known as ACCESS, which viewed the anticipated effects in the Arctic [2]. The problem with this study is that it largely worked off of previous research and found little data itself. The study did, however, publish that monitoring of coastal states for enforcement of oil regulations is widely limited, and the oil companies largely operate with no oversight. Most of the data about the Arctic landscape is actually coming from these oil companies who claim they have plans in place to negate disturbance to the bears. However, the research has found this to be false, or to be based on limited observations.

Scientific data is largely coming from university biological departments and Alaskan and Canadian geological centers [7]. These scientists tag and observe polar bears over long periods of time, which has allowed the collection of new data about diet restrictions and trends. However, largely the arctic is still unknown [8].

Future Direction

Oil rigs in the habitat of polar bears is clearly a controversial matter. Therefore, an increase of research and knowledge of how this species functions is a vital baseline into negating the effects of oil drilling on the species. Ice data charts need to be researched, so that in the event of an oil spill, we know concentrations of ice and can effectively maneuver clean up teams. Research also needs to be implemented on oil pipes and the nature of oil when it is -34 degrees fahrenheit. We know that oil pipes become brittle in this temperature, so what can we do to make sure they do not burst? We also need further knowledge of polar bear migration patterns, as it is the only way to effectively know if there is drilling in an area harboring a den. This can be done through increased coloring and with increased research like that of the ACCESS project, where specific bears were traced and monitored. This allows us to gain a better understanding of this species on an individual level. The U.S. Coast Guard also needs to increase their presence during winter, as these are the times oil drilling is most prevalent. Right now, their presence in the Arctic and their oversight is incredibly limited, which does little to help polar bears [8]. An increased understanding and heightened oversight is the best way to make applicable changes, ensure the safety of the polar bears, and minimize our impact on an already teetering ecosystem.

Conclusion

The overall trend of Arctic destruction is increasing, which presents cataclysmic problems for polar bears and their habitats. The problem is that research as of now is too limited and too focused on the melting ice. While the ice does pose a risk to the polar bears, previous literature suggests that oil drilling and its effects are more devastating to the polar bears right now. More funding and research is necessary going forward to address the effects of oil drilling on polar bears.

References

  1. Stirling, A. Derocher. “Effects of climate warming on polar bears: a review of the evidence.” Wiley online library, no. 10.111 ( 2012). https://onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2486.2012.02753.x.
  2. Crépin. et al. 2017. “Arctic climate change, economy and society (ACCESS): integrated perspectives.” NCBI, no. 10.1007 (2017): 341-354.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5673869/.

  1. L. Bettino. Et al. “Impacts of drilling in the arctic national wildlife refuge,” UMASS. https://blogs.umass.edu/natsci397a-eross/impacts-of-oil-drilling-in-the-arctic-national-wildlife-refuge/.
  2. The Congressional Digest. Oil drilling in Alaska. no. 80-6 (2001): 161-192. http://unc.summon.serialssolutions.com.libproxy.lib.unc.edu/.
  3. E. Alison. Et al. “Oil and gas in the arctic.” American Geosciences, no. 12-1:12-4 (2018). https://www.americangeosciences.org/sites/default/files/AGI_PE_Arctic_web_final.pdf.
  4. Environmental Pollutions Center. “Environmental Effects of Oil Spill.” Environmental Pollutions Center, 2017.

https://www.environmentalpollutioncenters.org/oil-spill/effects/.

  1. A.M. Pagano. Et all. “High energy, high fat lifestyle challenges an artic apex predator, the polar bear.” Sciencemag, no. 10.1126 (2018). https://science.sciencemag.org/content/359/6375/568.abstract.
  2. Glickson. Et all. “Responding to oil spills in the U.S. arctic marine environment.” National Academies of Science , Engineering and Medicine, no. 10.17226 (2014). http://dels.nas.edu/Report/Responding-Spills/18625.

About the author

He attends the University of North Carolina at Chapel Hill, majoring in Biology and History. He has a passion for climate change and climate activism. One day, he hopes to attend medical school using his schooling to pursue equality in medical treatment around the world, while still continuing climate discussion.

Leave a Reply

Your email address will not be published. Required fields are marked *