Climate change is having major ecological impacts on apex predators. Rising temperatures are causing sea ice to melt, which is destroying Arctic habitats for polar bears and reducing their ability to hunt seals. Warming oceans are also causing some aquatic predators like narwhals to shift their ranges northward or face local extinction. Increased wildfires due to climate change have burned over 70% of jaguar habitat in the Pantanal wetlands. Range shifts in predators and mismatches between predator/prey interactions will have cascading effects throughout ecosystems. Conserving apex predators will require expanding protected areas to allow range shifts and reconnecting fragmented habitats.

1. Ecological Impacts of Climate
Change on Apex Predators
Presenter:
Amit Chaudhary
Faculty of Forestry
Agriculture and Forestry University

2. OUTLINE
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1. Introduction
2. Literature Review
3. Discussion
4. Conclusion
5. References

3. ARCTIC FOOD WEB
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Source:
https://dribbble.com/shots/4021598-Arctic-Food-
Web

4. INTRODUCTION
 Apex Predators: The highest ranking predator in a food web of an ecosystem that
has no natural predators (Wallach et al., 2015).
 They influence their associated ecosystems through top-down forcings and
trophic cascades with their removal (Estes et al., 2011; Rod-Eriksen et al., 2022).
 Multitude of Ecological Impacts: Range shifts, habitat quality, the health of the
population, and change in consumer-resource interactions (IPCC, 2022b;
Parmesan et al., 2022).
 Climate change-intensified drastic conditions: droughts and sea ice melting,
intense bushfires, etc. disrupting the food chain in the Arctic fauna and contiguous
habitat of Jaguars in Pantanal (Laidre et al., 2020 Barros et al., 2022).
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5. MAJOR IMPACTS
1. Sea-ice decline, loss of habitat (hunting grounds) for arctic apex predators
like Polar bears (Ursus maritimus) (Atwood et al., 2017; PBSG, 2021).
2. Warming-related species range shifts and decline Narwhals (Modon
monoceros) (Chambault et al., 2020); Snow leopard (Panthera uncia) (Aryal
et al., 2016); Tiger (Panthera tigris) (Mukul et al., 2019).
3. Altered timing of seasonal species interactions Arctic Charr (Salvelinus
umbla) (Setzer & Jhonson, 2015).
4. Gradual or sudden decline in the population of tundra herbivores and
reciprocal effects on predators (Vulpes vulpes) (Rod-eriksen et al., 2022).
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6. MELTING SEA ICE:
Marine Heat Waves (MHW) and rise
in oceanic temperature are causing
cascading effects on sea-ice-dependent
polar bear food chains (IPCC, 2022b).
Untimely melting of sea ice and late
formation is causing disruption in the
hunting of seals (Phoca hispida and
Erignathus barbatus) in the Arctic.
Three subpopulations are at a
declining rate (PBSG, 2021).
They are forced to be onshore in the
Baffin bay population for additional
30 days in the 2000s compared to the
1990s causing starvation (Laidre, et
al., 2020).
Sea ice melting made predation
difficult and higher energy expenditure
in foraging activity led to a decline in
body condition. However, it couldn’t
be linked to the reproductive success
of polar bears (Pagano et al., 2018).
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7. AQUATIC PREDATORS
 The Pacific MHW of 2014 – 2016, when the abundance and quality of key
forage species like Capelin (Mallotus catervarius); Herrings (Clupea pallasii)
in the Gulf of Alaska reduced causing trophic disruptions in higher predators
and marine mammals (Arimitsu et al., 2021).
 A case of trophic mismatch was studied in the case of Arctic charr (Salvelinus
umbla) suggesting a difference in dates of emergence of fish fries and
zooplanktons caused the population decline due to resultant nutritional stress
(Setzer & Jhonson, 2015).
Sea ice melt also has reduced the krill numbers with altered distribution
causing an impact on major elements of the Southern Ocean food web including
whales, seals, penguins and albatrosses (Convey & Peck, 2019).
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8. ALTITUDINAL & LATITUDINAL
SHIFT
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Species of the terrestrial and aquatic ecosystems, have shifted their geographical
ranges to higher latitudes in response to the warming (Pörtner et al., 2022).
Expansion of snow leopard habitat in Central Asia (Li et al., 2016).
Bowhead whales (Balaena mysticetus) and other sub-arctic whales have benefitted
them in regards to better nutritional conditions (Post et al., 2019).
Warming causes physiological as well as nutritional stress in Narwhals causing
them to migrate further North of Green land Sea or locally go extinct with rising
oceanic temperatures (Chambault et al., 2022).
These were not an option for apex predators in the arctic and the other marginal
habitats like Sundarbans.

9. WILD FIRE
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Due to rising temperature and increased aridity in the terrestrial biomes like
Pantanal; wildfires have caused a significant loss- 79% of the home range of
Jaguar (Panthera onca) with the rise in intensity of the series of fire in 2020
(Barros et al., 2022).
The fire in the Pantanal affected 31% of the whole biome. Long-term
impacts include: displacement, hunger, dehydration, territorial defense, and
lower fecundity may affect the abundance of the species and are expected to
become more intense.

10. FLOODING
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In Brazilian Paraná the Caiman (Caiman latriotris) suffered from El Niño-
related floods due to inundation of the flat floodplain in a forest area
(Herrera et al., 2014). It caused the loss of egg-laying grounds.
The loss of coastal habitat of Sundar bans, on the Bangladesh side is projected
to be a nearly complete loss (99.4%) by 2070 under the worst-case scenario of
climate change and will be unfavorable to the Bengal Tiger Population in the
area. due to climate change and sea level rise (Mukul et al., 2019).

11. DISCUSSION
Some of the apex predators are coping with climate extremities as they have
climate refugia to reside (Li et al., 2016; Thapa et al., 2022). Such climate
refugia is limited for the species living in the margin such as the polar apex
predators which would suffer range contraction.
Recovery efforts focus on the restoration of natural processes through the
reintroduction of top predators and designing larger protected areas covering a
greater part of the landscape (Li et al., 2016; Thapa et al., 2022).
With the evident northward range expansion of the Bengal tiger as well as
Striped Hyaena (Hyaena hyaena) demands an extension of the protected areas in
their microrefugia like Chure and Mahabharat hills (Thapa et al., 2022).
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12. CONCLUSION
Apex predators are susceptible to consequences of rising atmospheric
temperature melting sea ice, warming oceans, melting glaciers, rising sea
level, and intense wildfires.
It causes nutritional stress altering its physiology and reproductive function;
range contraction ultimately results in a declining population of these already
threatened species.
Apex predators are important in terms of their regulatory function in the
ecosystem. More research into the phenological changes and the resultant
prey-predator dynamics would help in developing appropriate conservation
measures.
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13. THANK YOU
FOR YOUR ATTENTION!
Requesting your valuable
feedback
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References
 Aryal, A., Shrestha, U. B., ..........., & Raubenheimer, D. (2016). Predicting the
distributions of predator ( snow leopard ) and prey ( blue sheep ) under climate
change in the Himalayas. 4065–4075. https://doi.org/10.1002/ece3.2196
 IPCC. (2022b). Climate Change 2022: Impacts, Adaptation, and Vulnerability.
Contribution of Working Group II to the Sixth Assessment Report of the
Intergovernmental Panel on Climate Change (H.-O. Pörtner, D. C. Roberts, M.
Tignor, E. S. Poloczanska, ....., & B. Rama (eds.)). Cambridge University Press.
New York NY, USA.
 Laidre, K. L., Atkinson, S., Regehr, E. V., Stern, H. L., Born, E. W., Wiig, Ø., Lunn,
N. J., & Dyck., M. (2020). Interrelated ecological impacts of climate change on an
apex predator. Ecological Applications, 30(4). https://doi.org/10.1002/eap.2071
 Post, E., Alley, R. B., ......., & Wang, M. (2019). The polar regions in a 2 ° C warmer
world. Science Advances, 5(eaaw9883), 1–12.
https://doi.org/10.1126/sciadv.aaw9883
 Thapa, K., Ambuhang, S., ..........., & Malla, S. (2022). Wildlife in climate refugia :