Oceans And Their Threats

by Hrushitaa Murali (She/Her)

Oceans, or Marine Ecosystems, provide the perfect home for several phenomenal species groups, and are a source for nourishment, growth, development, and, gradually, evolution in response to changing circumstances. Given their vast global coverage, oceans are able to host over 175,000 species and are thus an integral factor to consider when framing and implementing policy decisions on biodiversity conservation [1].

This article provides an overview of the various threats oceans face, from two points of view: threats to the marine ecosystems, and threats as a result of marine ecosystem degradation to Indigenous Communities and Displaced Persons.

Perspective One: Oceanic disruption causing ecosystemic catastrophes

Plastic pollution is a major contributor to the emergence of large-scale resource deprivation in marine ecosystems. The most significant evidence of the negative impacts of plastic pollution is located in the middle of Earth’s largest ocean  – commonly known as the Great Pacific Garbage Patch, or GPGP. The gravity of the perils of plastic pollution in our oceanic bodies is accurately depicted by this 100 feet deep mass of accumulated plastics, with a total expansion of over 1.5 times the area of the United States of America [2, 3].

Another major peril to marine habitats is the phenomenon of eutrophication, which entails the washing off of excessive plant nutrients, such as phosphorus and nitrogen. An uncontrolled or unmonitored eutrophication can lead to an exponential increase of the harmful marine algae population, which harms the general quality of life of other organisms in marine ecosystems [4]. A key contributor to eutrophication is agricultural activity, such as excessive irrigation (required for cultivation of crops such as rice) and the washing off of pesticides from a harvested field. Increased human interventions can damage the natural progression of eutrophication, delaying (or in the worst case inhibiting) the recovery of habitats to their original state.

Perspective Two: Are we truly safe if our home is slowly decaying?

The rapid pace of marine habitat destruction is set to pose a massive threat to human food supplies in various ways:

  • Abrupt shifts in food chains, acutely recognised to endanger the top predator (humans, as a result of activities including hunting and poaching for commercial purposes)
  • Higher medical risks to humans due to biomagnification; biomagnification is the subsequent overall increase in toxins as energy passes upwards along a food chain [5]. As top predators and at the top of the food chain, human beings are the most susceptible to the harms from biomagnification.
  • Marine habitats in particular are a major source of water as a resource for human consumption. Without accessible potable water, water-borne diseases and epidemics are much more likely to spread, further decreasing human quality of life and increasing the probability of human extinction. [11]

      The ocean may be scary, but are we scarier?

      The state of marine habitats today is a result of the irreverent exploitation of natural resources by human beings [12]. Several marine ecosystems are rapidly approaching their tipping points, which when reached, can result in irreversible damage to the ecosystem’s biodiversity. In addition to the problems caused in oceanic ecosystems, there is a pervasive threat to the food sources of communities who are directly dependent on marine ecosystems for their survival: namely, indigenous groups and coastal communities. These frontline communities have witnessed catastrophic displacement, which is indirectly related to the overexploitation of natural resources by individuals and corporations entirely unrelated to these communities [13].

      How are endangered communities coping and fighting back?

      Indigenous communities and displaced persons are at the forefront of the climate crisis and are continually adapting to the changing conditions around them [13]. These communities are attempting to combat a phenomenon that was not caused by their activities or their overexploitation of the natural resources accessible to them.

      Several activist groups are focussed on obtaining a secure status of existence for these indigenous communities, through policy changes or additions to existing policies that would enable legitimate ownership of protected lands by these endangered communities [8].

      Indigenous communities have a long history of living in harmony with the marine environment and protecting its biodiversity [13]. They have developed traditional knowledge and practices that help them manage their resources sustainably and adapt to changing conditions. Some of the efforts taken by indigenous communities to protect marine habitats include [9,10]:

      • Establishing Marine Protected Areas (MPAs) that recognize and respect their rights, values and governance systems. Participating in co-management and stewardship initiatives that involve collaboration and partnership with other stakeholders, such as governments, NGOs, researchers and industry.
      • Advocating for the recognition and protection of their rights, interests and responsibilities in relation to the marine environment. Indigenous communities can use various platforms and mechanisms to assert their rights to self-determination, free prior and informed consent, access to resources, benefit-sharing, cultural expression and environmental justice.
      • Sharing their knowledge and experiences with other indigenous communities and the wider society. Indigenous communities can use various media and methods, such as storytelling, art, film, education and research, to communicate their perspectives and insights on marine conservation and management.

        Indigenous communities have long been stewards of the marine habitats that sustain their livelihoods and cultures [13]. Despite facing historical and ongoing challenges such as colonisation, dispossession, and marginalisation, they have shown remarkable resilience and innovation in protecting and restoring the health of the oceans. Indigenous communities have demonstrated their commitment and leadership in safeguarding the marine environment for present and future generations.


        [1] https://obis.org/, Accessed on 16th February 2023
        [2] Thomas M. Kostigen, The World’s Largest Dump: The Great Pacific Garbage Patch, Discover Magazine, https://www.discovermagazine.com/environment/the-worlds-largest-dump-the-great-pacific-garbage-patch, Accessed on 16th February 2023
        [3] Grant Harse, 2011, Plastic, the Great Pacific Garbage Patch, and International Misfires at a Cure, UCLA Journal of Environmental Law and Policy, DOI:10.5070/L5292019968
        [4] Patricia M. Gilbert, Eutrophication, harmful algae and biodiversity — Challenging paradigms in a world of complex nutrient changes, Marine Pollution Bulletin, DOI: https://doi.org/10.1016/j.marpolbul.2017.04.027
        [5] M. Nendza et al., Potential for secondary poisoning and biomagnification in marine organisms, Chemosphere Journal, DOI: https://doi.org/10.1016/S0045-6535(97)00239-7
        [6] Tien Ming Lee et al., 2023, Growing disparity in global conservation research capacity and its impact on biodiversity conservation, One Earth Journal, DOI: https://doi.org/10.1016/j.oneear.2023.01.003
        [7] S.C Gall and R.C Thompson, The impact of debris on marine life, Marine Pollution Bulletin, DOI: https://doi.org/10.1016/j.marpolbul.2014.12.041
        [8] United Nations Department of Economic and Social Affairs. Challenges and Opportunities for Indigenous Peoples’ Sustainability, United Nations Website, https://www.un.org/development/desa/dspd/2021/04/indigenous-peoples-sustainability/, Accessed on 2nd March 2023
        [9] North, Potter, Potter, Huntington, Huntington, Westdal, & Westdal. (2023). Indigenous Protected Areas & Marine Conservation. Retrieved 11th March 2023, from https://www.oceansnorth.org/en/what-we-do/indigenous-protected-areas-marine-conservation/
        [10] Owen-Burge, C. (2022). Marine Protected Areas: Restoring, preserving, and protecting the integrity and resilience of our ocean for future generations – Climate Champions. Retrieved 12th March 2023, from https://climatechampions.unfccc.int/marine-protected-areas-restoring-preserving-and-protecting-the-integrity-and-resilience-of-our-ocean-for-future-generations/
        [11] Mora, C., Wei, C., Rollo, A., Amaro, T., Baco, A., & Billett, D. et al. (2013). Biotic and Human Vulnerability to Projected Changes in Ocean Biogeochemistry over the 21st Century. Plos Biology, 11(10), e1001682, DOIL https://doi.org/10.1371/journal.pbio.1001682
        [12] Crain, C. M., Halpern, B. S., Beck, M. W., & Kappel, C. V. (2009). Understanding and Managing Human Threats to the Coastal Marine Environment. Annals of the New York Academy of Sciences, 1162(1), 39-62. https://doi.org/10.1111/j.1749-6632.2009.04496.
        [13] Lauer, M., & Aswani, S. (2010). Indigenous Knowledge and Long-term Ecological Change: Detection, Interpretation, and Responses to Changing Ecological Conditions in Pacific Island Communities. Environmental Management, 45(5), 985-997. doi: https://doi.org/10.1007/s00267-010-9471-9
            Categories Biodiversity/Uncategorized

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