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Climate Change to Cause Polar Bear Population Declines

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By Laura Vander Meiden, SRC Intern

Over the next 35-40 years polar bear populations have the potential to decrease by more than 30% according to an assessment by the International Union for Conservation of Nature (IUCN). The report cites climate change and the resulting loss of sea ice as the cause of this probable decline.

Photo by Ansgar Walk vie Wikimedia Commons.

Photo by Ansgar Walk vie Wikimedia Commons.

 

Polar bears are specifically built to survive the harsh conditions of the arctic. Their adaptations include two types of insulating fur, a deep layer of fat to keep warm while in the water, bumps called papillae on the bottom of their feet for grip on ice, and feeding behaviors designed for living on the ice. Ironically it is these adaptations that make polar bears most vulnerable as the climate changes.

Scientist’s primary concern is the effect melting sea ice has on the eating habits of the bears. Though polar bears have been seen to opportunistically feed on a variety of organisms, their primary source of food is ring seals which live on the edge of the ice. The seals have a very high calorie content, particularly in their blubber, which is necessary for the polar bear’s frigid lifestyle. This allows the bears to build up large fat reserves which are critical as the bears can only hunt seals when there is ice. When seasonal ice melts in the summer, the bears typically must fast, living off their fat reserves, until the ice returns in the winter.

As climate change continues the ice will melt more quickly each summer and take a much longer time to return each winter. This extends the length of time polar bears must fast, resulting in higher chances of starvation. Melting ice and the subsequent reduced access to food can also lead to an overall decrease in body condition, reduced survival rates of cubs, loss of denning habitat and increased drowning as the bears attempt to swim between ice floes.

Polar bears are found on four different sea ice regions. The populations found in the region where ice is the most seasonal are at present in the most danger from climate change. Also vulnerable are populations in the divergent ice region where ice forms along the shore, but is not always connected to pack ice further out to sea. Safest are populations in the region where convergent ice connects the bears to pack ice and the archipelago region where ice remains year round. The latter region is expected to be the final refuge of the bears, but unless carbon dioxide emissions are reduced even this ice will be melted in 100 years.

Of 19 subpopulations 3 are declining, 6 are stable, 1 is increasing, and 9 have insufficient data to make a determination. Map via Norwegian Polar Institute.

Of 19 subpopulations 3 are declining, 6 are stable, 1 is increasing, and 9 have insufficient data to make a determination. Map via Norwegian Polar Institute.

While the situation for the polar bears appears dire, scientists have not completely lost hope. If significant reductions are made in greenhouse gas emissions, the amount of time before the sea ice melts could be extended. However scientists warn that action must be taken soon, since once a tipping point is reached sea ice will decrease rapidly and no amount of emission reduction will be able to stop the ice from melting.

Effects of Global Warming on Polar Bears in the Arctic

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by Dani Ferraro, RJD intern

Global warming and the loss of Arctic sea ice is affecting populations of polar bears (Ursus maritimus) in Hudson Bay. Localized rises in sea surface temperatures (SST) have lead to mortality events and habitat changes for several marine species (Dulvy et al. 2008). While some species have adaptations that allow them to tolerate warming events, the loss of habitat and consequent die-offs of prey species is devastating.  The Hudson Bay Lowlands (HBL), the second largest inland sea in the world and home to polar bears, has warmed approximately three degrees Celsius since the 1990s (Ruhland et al. 2013).  With warmer air temperatures and increasingly rising SST comes the loss of winter ice-cover and reduced snow depth. This has directly caused the mortality of polar bear cubs and their prey, the ringed seal (Phoca hispida) and the bearded seal (Erignathus barbatus). As the forage and movement patterns of ringed seals and closely linked with sea ice, loss of this habitat could explain this mortality. The latest population estimates are about 21,500-25,000 individuals throughout the circumpolar Arctic (Luque et al. 2014).

Ice formation in early November in Hudson Bay, Canada. Image Source: Wikimedia Commons

Ice formation in early November in Hudson Bay, Canada. Image Source: Wikimedia Commons

As a k-selected species, polar bears have delayed maturation and high adult survival rates, but smaller litter sizes. Sea ice acts as a polar bear’s hunting grounds, with terrestrial habitats as their maternity and breeding grounds. For female polar bears, impacts beyond loss of habitat exist. With reduced sea ice, females will have a cascading loss of adipose stores, causing lowered reproductive rates. This loss of adipose means that females have less fat to invest in their cubs throughout the winter season and subsequent fasting season. With reducing sea ice thickness, it becomes thinner and more pliable to winds and currents. Polar bears will respond with increased walking or swimming, using higher energy in order to retain their habitat range.

It’s important to acknowledge the differences in sea ice thickness and location. Polar bears prefer the annual sea ice located over the inter-island archipelagos and continental shelf surrounding the polar basis. This sea ice has declined in near shore areas and in amount of multiyear ice. With this decline comes the decrease in preferred habitat locations for polar bears, as well as other pagophilic species throughout the arctic marine ecosystem. Large expanses of open water due to melting sea ice often separates terrestrial maternity dens from residential pack ice. Pregnant females have a tendency to leave their residential areas during ice break-up and remain separated throughout the summer. In order to endure the summer before they can return to sea ice to feed, females need to have built up sufficient fat stores to sustain themselves for at least 8 months. However, considering the preferred location of polar bears: the deep polar basin, where there is a lower seal density, females will find difficulties obtaining sufficient fat stores. Without having accumulated adequate adipose stores, females have fewer nutrients to pass along to nursing cubs. Due to lower energy and fat stores, females are more likely to give birth to single cub litters, often with low survival rates caused by small body mass (Derocher).

Image 2 Ferraro

Polar Bear (Ursus maritimus) Image Source: Wikimedia Commons

 

 

With increasing SST and breaking sea ice, polar bears use more energy moving against the direction of ice drift. If ice moves more quickly, more energy is needed to move and hunt accordingly. Once sea ice concentration falls below 50%, polar bears tend to stick to terrestrial environments. Hunting and hauling prey onto land is energetically costly, requiring older polar bears to consume more, leaving fewer scraps for juveniles to scavenge. Combined with lower female productivity, the loss of food for juveniles doesn’t bode well for polar bear populations in the future. The impacts of climate change and global warming are already being seen with increasing sea surface temperature and decreasing sea ice depth. These habitat changes cause a cascading shift down the Arctic ecosystem, from habitat loss to mass mortality and reduced productivity. There will be shifts in survival rates, maturation age, and reproductive rates in populations of polar bears as well as that of its prey, both the bearded seals and ringed seals. With such a limited habitat in the circumpolar Arctic, global warming and climate change have a drastic effect on their populations, environments, and breeding habits.

 

 

Derocher, A. (2004). Polar Bears In A Warming Climate. Integrative and Comparative Biology, 163-176.

Dulvy, N.K., Rogers, S.I., Jennings, S., Stelzenmuller, V., Dye, S.R. & Skjoldal, H.R. (2008) Climate change and deepening of the North Sea fish assemblage: a biotic indicator of warming seas. Journal of Applied Ecology, 45, 1029–1039.

Luque, S., Ferguson, S., & Breed, G. (2014). Spatial behaviour of a keystone Arctic marine predator and implications of climate warming in Hudson Bay. Journal of Experimental Marine Biology and Ecology, 504-515.

Ruhland, K., Paterson, A., Keller, W., Michelutti, N., & Smol, J. (2013). Global warming triggers the loss of a key Arctic refugium. Proceedings of the Royal Society B: Biological Sciences, 20131887-20131887.

Climate Change and Corals: Is it too late?

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By Jacob Jerome, RJD Graduate Student and Intern

There have been numerous studies that focus on the alterations that climate change can have on the marine environment and how those alterations affect corals. In the marine science field coral bleaching and the disappearance of coral reefs is widely discussed. One of the primary debates centers around whether or not it is too late to save coral reefs. But is this doom and gloom viewpoint how we should be looking at this situation? Many scientists argue that there is still hope for coral reefs.

It is important to first understand the threats that climate change pose to corals. There are two main threats: a rise in ocean temperatures and a lowering of the ocean’s pH, a process known as ocean acidification.

Higher temperatures stress corals and cause them to lose their symbiotic algae, or zooxanthellae (NOAA,2011). These symbiotic algae are what give corals their color and without them the corals turn white, an event known as coral bleaching. This bleaching can have several negative impacts on the coral polyps. Corals and their symbiotic algae have what is called a mutualistic symbiotic relationship; this is a relationship where both species benefit from interacting with one another. Corals provide their symbiotic algae with a protected environment and compounds they need for photosynthesis. The symbiotic algae, in return, provide corals with the products of photosynthesis, a suite of compounds that provide food for the corals and aid in the production of calcium carbonate. Although still alive, by losing their symbiotic algae, corals experience increased stress and are more prone to disease (NOAA, 2011).

OLYMPUS DIGITAL CAMERA

A clear depiction of coral bleaching (Joe Bartoszek 2010/Marine Photobank)

Ocean acidification occurs due to the overwhelming amount of carbon dioxide that is absorbed into the ocean from the Earth’s atmosphere. When carbon dioxide is absorbed into the water, the pH of the water decreases and the water becomes more acidic. Low pH waters limit the rate at which corals can produce calcium carbonate and also increase the rate at which calcium carbonate dissolves (Andersson et al., 2014). Corals use calcium carbonate to build their hard exoskeleton. If corals are not able to produce calcium carbonate quicker than the rate at which it dissolves, they cannot grow.

Knowing these threats, many assume that corals have little hope for surviving through the end of this century. According to the Status of Coral Reefs of the World: 2008, 19 percent of the world’s coral reefs are gone or cannot recover, 15 percent are seriously threatened, and 20 percent are under the threat of loss within the next 20 to 40 years. So, is it too late for corals? Are these threats too great for us to effectively manage them? New scientific research indicates that not all corals are quite ready to give up.

Figure 2

A table summarizing the status of the world’s coral reefs in 2008 (Wilkinson, C. 2008)

Just last year, Australian scientists discovered that coral animals alone are able to produce dimethylsulphoniopropionate (DMSP), a sulphur-based molecule with properties that can provide protection on a cellular level to corals in times of heat stress (Raina et al., 2013). This was the first time that an animal had been discovered to produce DMSP. They also found that corals increased their production of DMSP when subjected to higher water temperatures (Raina et al., 2013). This new information illustrates that corals, even without their symbiotic algae, can “fight” against temperature shifts. While this does not mean that corals can entirely defend themselves against rising temperatures, it does indicate an ability to adapt, to an extent, to these changes.

In addition, a study in the Cayman Islands revealed that a coral reef system that suffered a 40 percent reduction in corals due to bleaching and diseases was able to recover seven years later (Manfrino et al., 2013). The corals in the Cayman Islands are known to be healthy and are afforded some protection from fishing and anchoring. This protection definitely aided in their recovery along with their isolation, a small human population, and a generally healthy ecology (Manfrino et al., 2013). Nonetheless, the Cayman Islands can serve as an example of what can happen when reef management is taken seriously.

In Palau, something remarkable has been discovered. By taking water samples from 9 different locations that stretched from open ocean, across a barrier reef, and into a lagoon and bays, scientists discovered that the sea water became increasingly acidic as they moved toward land (Shamberger et al., 2014). What was even more surprising was that the level of acidity was as high as scientists had predicted for the open ocean by the end of this century. Even so, healthy and diverse coral reefs were found in these areas. In fact, the corals appeared healthier in the more acidic areas than they did in the less acidic areas (Shamberger et al., 2014). While these results are incredible, caution should be taken when interpreting them. The environment surrounding the corals of Palau might create a “perfect storm” for environmental conditions that allow the corals to survive in the acidic waters. Even so, this area has been functioning the same way for thousands of years and may have unintentionally modified the corals in that area genetically. If this is the case, those corals can essentially be put in other acidic environments and survive. This discovery could have huge implications for the survival of corals.

It is important that we do not lose sight of the fact that these new discoveries do not mean that corals are safe under ocean conditions that have resulted from climate change. It does mean, however, that there is still hope for some corals. Climate change is difficult to prevent and changing human habits can be even harder. But if we can release the myriad of other stresses that are put on corals and think about our carbon footprint, corals just might stand a chance for their beauty to be enjoyed for generations to come.

 

References

Andersson, A. J., Yeakel, K. L., Bates, N. R., de Putron, S. J. (2014). “Partial offsets in ocean acidification from changing coral reef biogeochemistry.” Nature Climate Change, 4(1): 56–61.

“Coral Bleaching And Ocean Acidification Are Two Climate-Related Impacts to Coral Reefs.” How Is Climate Change Affecting Coral Reefs? Ed. National Ocean Service. NOAA, 8 Dec. 2011. Web. 10 Mar. 2014. <http://floridakeys.noaa.gov/corals/climatethreat.html>.

Manfrino, C., Jacoby, C.A., Camp, E., Frazer, T.K. (2013). “A Positive Trajectory for Corals at Little Cayman Island.” PLoS ONE, 8(10): e75432.

Raina, J.B., Tapiolas, D.M., Forêt, S., Lutz, A., Abrego, D., Ceh, J., Seneca, F.O., Clode, P.L., Bourne, D.G. Willis, B.L., Motti, C.L. (2013). “DMSP biosynthesis by an animal and its role in coral thermal stress response.” Nature, 502: 677-680.

Shamberger, K. E. F. Cohen, A.L., Golbuu, Y., McCorkle, D.C., Lentz, S.J., Barkley, H.C. (2014). “Diverse coral communities in naturally acidified waters of a Western Pacific Reef.” Geophysical Research Letters, 41: 499–504.

Wilkinson, C. (2008). Status of the Coral Reefs of the World: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Centre, Townsville, Australia, 296p. Reefcheck.org 3/10/2014.

Seafloor Biomass and Climate Change

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By: Patrick Goebel, RJD Intern

The bottom of the ocean is a dark and mysterious place. It was first believed that this was a lifeless barren dessert. However, in recent years our understanding of this wasteland has changed. Submersible submarines, baited cameras and core samples have shown that life can survive at these deep depths. Animals and organisms have adapted to low temperatures, extreme pressure and minimal food. On the ocean seafloor, there is a plethora of organisms that play a vital role in the marine ecosystem. The vast majority of these organisms depend on the upper ocean as a source of energy. Energy on the seafloor is derived from particulate organic carbon (POC) from the upper ocean.

A recent article, Global reductions in seafloor biomass in response to climate change, predicts that biomass will decrease in response to climate change. Eight fully coupled earth system models were used to construct a multi-model mean of export flux. The model used two different Representative Concentration Pathways, one moderate and one high. The export flux estimates are used in conjunction with published empirical relationships to predict changes in benthic biomass (Jones et al 2013).

The article predicts that the upper ocean biomass will decrease in response to climate change, which will result in a decrease of POC that is transferred to the ocean floor.  Benthic communities are already limited by food supply and further depletion could change the diversity and structure of these communities. The total seafloor biomass is predicted to decrease by 5.2%. There will also be a shift in benthic infauna toward smaller size classes. Macrofauna will decrease far more than meiofuanal and megafaunal. This is most likely due to the greater energy demand of macrofauna.

Goebel figure 1

Change in Biomass % over 90 yrs (Jones et al 2013)

Since not all oceans are the same, some will experience a decrease while others will experience an increase. The Atlantic, Pacific and Indian oceans are predicted to see a reduction in POC flux and biomass. However, the Southern and Artic Ocean are projected to experience biomass increases. There are many canyons, seamounts and cold-water corals located in these oceans that will largely be affected. More than 80% of potential deep-water biodiversity hotspots known around the world, including canyons, seamounts, and cold-water coral reefs, are projected to experience negative changes in biomass.

In conclusion, there will generally be a decrease in POC as a result of anthropogenically induced warming. However, there are other factors, such as, decreased oxygen, change in pH, and fishing pressure that could also have a negative impact on seafloor biomass.  These factors will likely contribute to a decrease in seafloor biomass and cause for under representation of the 5.2% decrease. The loss or decrease of benthic communities will have a negative impact on the ocean ecosystem, as these communities play a vital role in contributing to elemental cycling, benthic remineralization and carbon sequestration (Jones et al 2013).

 

Jones, D. O., Yool, A., Wei, C. L., Henson, S. A., Ruhl, H. A., Watson, R. A., & Gehlen, M. (2013). Global reductions in seafloor biomass in response to climate change. Global change biology.

How Climate Change Affects Marine Species, their Environments and the U.S. Endangered Species Act

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By Jacob Jerome, RJD Intern

Despite a frigid winter in a large portion of the U.S., global climate change is upon us and average global temperatures are increasing. Many of us think about how climate change will affect us personally, but forget that it affects marine species too, especially those that are threatened or endangered. Seney et al published a paper in 2013 that reviewed the potential effects that climate change poses on species and ecosystems, and how it effects decision making under the Endangered Species Act (ESA).

Worldwide climate change documentation indicates mean surface air temperatures are increasing, along with the upper layers of the ocean.  Due to our growing planet, the abundance of carbon dioxide in the atmosphere has caused the surface waters of the oceans to become more acidic. With this type of data, projections have been made to see how our climate will change in the 21st century.  Assuming no reduction in carbon emissions, it is predicted that surface air temperatures will increase even more, the sea level will rise, and the pH of the ocean will continue to drop.

These environmental changes can affect species through habitat loss or alteration, distribution changes, geographic isolation, or changes in predator-prey interactions. Even human adaptations to climate change such as relocation or changes in fishing and agriculture could potentially impact species through habitat conversion and ecological degradation.

Jerome Fig 1

Schematic showing the multiple interactions among species, their ecosystems, and climate effects (Seney et al., 2013).

So what does all this mean for the conservation and management of marine species? In 1973 the United States implemented the Endangered Species Act (ESA) in an effort to prevent species’ extinction and promote their recovery. While this continues to be one of the United States’ best laws protecting various species, it was not originally intended to factor in climate change. Luckily, the ESA emphasizes the importance of habitats and ecosystems to endangered and threatened species and therefore can afford protection in the event of climate change. To make this happen, climate change needs to be considered in five key ESA decisions: listing determinations, designation of critical habitat, recovery planning, accessing and mitigating effects of proposed federal actions, and issuance of incidental take permits. These decisions for marine species fall to the National Marine Fisheries Service (NMFS) of the National Oceanic and Atmospheric Administration (NOAA).

Listing determinations refers to how a species’ status is determined, whether threatened or endangered. According to the ESA, an endangered species “is in danger of extinction throughout all or a significant portion of its range” and a threatened species “is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” Climate change can affect listing decisions if it can present new threats that affect species persistence or add to existing threats.

Critical habitat of listed species is “physical or biological features essential to the conservation of the species and which may require special management considerations or protection.” The boundaries of critical habitat for species could change for those that modify their range when reacting to climate change. To better address this, agencies should look outside currently occupied spaces for essential habitat in the event of climate change.

Jerome Fig 2

Rising air temperatures are causing glaciers in the north to break apart and melt, a contributing factor to the rise in sea level. (Thomas Hallermann/Marine Photobank)

Recovery planning takes place for every species that is listed under the ESA, making it vital for agencies to provide guidelines on how to promote the recovery of species. Climate change was not addressed in past recovery plans, but since 2008, over half of the recovery plans drafted included climate change — information that is imperative when working to conserve the most endangered species.

When federal actions are proposed, conservation planners look to see how the action will affect species and their ecosystems. While it is difficult, projecting how those actions will look after climate change would help to better protect species against potentially harmful actions.

If agencies provide permits that allow the take of ESA listed species in connection with certain activities, they must consider the effects of climate change on future environmental conditions when determining the approval of a permit. This will help to ensure that the permit does not add a higher degree of risk to the species’ survival.

Through these actions, we may be able to strengthen the ESA, allowing even better protection for threatened and endangered species.

 

Reference

Seney, E.E., Rowland, M.J., Lowery, R.A., Griffis, R.B., and McClure, M.M. “Climate Change, Marine Environments, and the U.S. Endangered Species Act.” Conservation Biology. 27.6 (2013): 1138-1146.

Sea Level Rise: How bad is it really going to be?

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by Gabi Goodrich, RJD Intern

For years scientists have been discussing the effects of global warming, carbon emissions and those effects on the oceans. But how bad is it really? Currently the rate of sea-level rise is about 3.2 millimeters per year (about .13 inches per year) [1].  However, with our current output of carbon emissions, scientists say that rate will increase tenfold. This means we have “locked in” a fate of sea levels rising 1.3 – 1.9 meters (4.27 – 6.23 feet) higher than today. Anders Levermann and his team of scientists have found that the sea levels are hyper sensitive to global warming. In fact, for every degree Celsius increase in global temperature, sea levels will rise about 2.3 meters (7.55 feet).

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How will climate change affect the life cycles of fish?

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by Asta Mail, RJD Intern

In a coffee shop the other day, I overheard two teens discussing technology and how it affected their lives. “How did anyone ever grow up without cell phones?” they wondered aloud. “How did they know when and where to meet up?”

Hearing this, I began to consider the ways people navigate the world, and how differently we do so now than we did in the past. Today’s youth has quickly learned and adapted to a very different social climate than that the previous generation. Growing up in an age of rapid development, they are accustomed to regular advances in communication, travel, and social interaction. Young people encounter very different obstacles through the stages of their development than their parents once did.

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Climate change influences sea turtle nesting

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by Becca Shelton, RJD Intern

In David A Pike’s scientific paper Climate influences the global distribution of sea turtle nesting, Pike takes an in-depth look at which factors contribute to sea turtle nesting sites. There are 7 extant species of marine turtles that inhabit mainly tropical and subtropical waters and globally, are all considered to be endangered or threatened. Nesting site issues, whether they are abiotic or anthropogenic, appear to be a large contributor to sea turtle population decline. While there have been many studies on sea turtle nesting sites and conservation efforts to protect these areas, Pike’s study focuses more on the variables that attribute to the distribution of the ideal beaches for nesting and how future climate changes may affect them.

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Ocean Acidification and Your Dinner: Impacts of Marine Seafood

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By Emily Rose Nelson
RJD Intern

Ocean acidification is a term commonly used in the world of marine science. This process can most easily be described as the lowering of oceanic pH due to increased atmospheric carbon dioxide concentrations. However, there is much more to this complicated process, which could mean great changes for the future of our oceans.

It is no surprise that atmospheric carbon dioxide levels are increasing. Since the industrial revolution atmospheric CO2 concentrations have increased from 280 ppm to 396 ppm, and this number is expected to increase to 800 ppm by the year 2100. Unfortunately, much of this excess CO2 finds its way to the ocean, changing the natural chemistry of the water. When atmospheric CO2 is added to seawater a series of chemical reactions naturally occurs. The addition of excess CO2 shifts the equilibrium of this reaction series, resulting in increased hydrogen and lower carbonate concentrations. Because pH is equal to –log [H+] increased H+ concentrations have lowered the pH from pre-industrial 8.2 to a 7.8 (projected 2100). Carbonate is essential for calcifying organisms such as mussels, shrimp, some coral species, and more. Carbonate ions combine with calcium ions naturally found in seawater to form CaCO3, the skeletal material for many organisms. Lowered carbonate concentrations make it more difficult to form this compound, thus more difficult to calcify, and in some cases survive.

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The Effects of Climate Change on Top Predator Distribution

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by Jon Dorsey, RJD Intern

Climate change is a major concern that has been facing humankind for quite some time. Sea surface temperatures are predicted to rise between 1 – 6 degrees Celsius by 2100 and the consequences of this world-wide climate alteration include a loss of species richness, habitat shifts, and certain species endangerment. To measure the potential changes in habitat shifts of marine predators, the Tagging of Pacific Predators (TOPP) program designed an experiment where they would tag different Pacific marine predator species and track their behavior and migration patterns from 2000 – 2009. Along with the species tracking, they used functions of sea surface temperatures, chlorophyll A, and bathymetries to consolidate models that could allow the prediction of major marine predator habitat changes up until the year 2100. With this collected data, baselines would be set for which species require special management and which critical ecosystems are most at risk.

This diagram depicts the relative densities of top predators from 2001 -2009 In the Eastern Pacific Ocean.

The TOPP program chose to follow top predators because of the essential role they play in their environments. These predators provide a system of top-down control of ocean food webs and chains. Therefore, when a species is removed due to an environmental change, the stability of that marine ecosystem is jeopardized due to the resulting changes in the trophic cascade. The TOPP program collected sufficient results from 15 predator species and analyzed their individual tracks. Patterns in biodiversity indicated a northward movement in the core habitat, as a result of the northward swing of the NPTZ (North Pacific Transition Zone) and the richness decreased by 20%. In order to acclimate to these habitat shifts, predators were forced to live in unfamiliar environments in which not all of the species adapted well.

Predators within the shark, marine mammal, and turtle guilds have all shown declines in their new potential core habitats. The shark guild showed the most radical pelagic habitat loss with 3 out of every 4 species showing declines. Other species such as loggerhead turtle and blue whales also exhibited declines in their core habitats. One potential explanation is that these species have a lower capacity for adaptation due to their specialized diets. Their new environments may not cater to their specific diets which can cause an improper balance of nutrients in their diets. These decreases are alarming and it forces us to come up with potential ways to maintain stable predator populations.

These graphs display the predicted quarterly changes of population density for the tagged marine predators over the next century.

A primary way to maintain a healthy ecosystem should be to implement a system of marine ecosystem conservation and manage it proactively. The effects and rates of how the climate changes will impact different ecosystems will not be uniform. Therefore, it is crucial that we identify biodiversity hotspots that are at risk. Due to the shifting habitats, protected areas that would be oriented to transient oceanic features are being proposed. What this means is that areas where eddies, fronts, and upwellings are known to exist will be under a protected law due to the unstable and ever-changing dynamics. Climate change is a phenomenon affecting the whole planet and we must take preventative actions and develop recovery plans to protect the top predators that play vital roles in maintaining equilibrium in the marine environment.

REFERENCES:

Hazel, E et al. (2012). Predicted habitat shifts of Pacific top predators in a changing climate. Nature Climate Change