In the previous post, I introduced macroplastics and microplastics. For today, let us focus on its effects on animals. Some effects of plastics, especially that of macroplastics, are quite straightforward. These effects are easily observable with the naked eye.
(1) Entanglement
Macroplastics such as fishing gear, fishing nets, etc are often the cause of entanglements. Entanglements poses many potential problems. It can cause damage to body parts of animals such as deformations, skin lesions and even amputations over time (Werner et al., 2016). It could also cause long term impacts such as compromised mobility and other further impacts on the animal’s natural abilities. Notably, the most severe outcome of entanglement would be death.
(2) Ingestion
Plastics, both macro and micro, are consumed by animals frequently. Why do they do so? One possible explanation is that they do not know the difference between food and non-food since plastic coexists with food sources (Daly, 2019). Thus, often animals’ inability to detect the presence of plastic among food leads to the ingestion of plastics which lead to negative effects on it appetite mainly or damage to organs.
Some of you might be wondering ‘Don’t plastics float? Marine animals can just forage for food below surface’. Well, that is not entirely true. Many types of plastics naturally sink at some point of time. and even if they were to float, the growth of algae or barnacles on it would cause it to sink (Daly, 2019). Hence, plastic is found at a range of depths of oceans and is in the environment of many marine species which are unable to distinguish it from food.
(3) DEATH !!!
Often entanglement and ingestion can lead to death overtime. For instance, when entangled and unable to untangle itself, animals are unable to forage for food which then leads to starvation. Or, the animals might not be able to escape from predators. Furthermore, when animals are unable to excrete ingested plastics naturally, they accumulate in the animals’ stomachs. This can reduce their appetite and lead to starvation overtime (Parker, 2019). Lastly, plastics could also cause immediate deaths by blocking digestive tracts or impaling organs (Parker, 2019).
Apart from the obvious effects stated above, there are probably other effects that go unnoticed by the human eye at a glance. Hope you have understood the general impacts of plastics for animals.
What’s next?
Do microplastics cause the same effects? Any different effects due to microplastics?
Stay tuned for the next post to find out! 🙂
References
Daly, N. (2019). Why do ocean animals eat plastic? [online] Nationalgeographic.com. Available at: https://www.nationalgeographic.com/animals/2019/12/whales-eating-plastic-pollution/ [Accessed 28 Aug. 2020].
Hart, M.F., 2020. Ocean plastics, digital image, Available at: https://chinadialogueocean.net/14200-how-does-plastic-pollution-affect-the-ocean/ [Accessed August 30, 2020].
Parker, L. (2019). The world’s plastic pollution crisis explained. [online] Nationalgeographic.com. Available at: https://www.nationalgeographic.com/environment/habitats/plastic-pollution/ [Accessed 28 Aug. 2020].
Werner, S., Budziak, A., Franeker, J. van, Galgani, F., Hanke, G., Maes, T., Matiddi, M., Nilsson, P., Oosterbaan, L., Priestlans, E., Thompson, R., Veiga, J. and Vlatchogianni, T. (2016). Harm caused by marine litter. MSFD GES TG Marine Litter – Thematic Report. doi:10.2788/690366, European Union, pp.10–13.