So did you read the previous post and go “Come on Priya can you give me more details.. My brain can handle more information you know…”? Well, here I am, back with a post discussing some journal articles to give you some technical information.
Remember I talked about microplastics in fin whales? Well, I went to search out a journal article about it to give you more information about it. In the study, phthalates were detected and measured in surface neustonic/planktonic and water column samples as well as stranded whale specimens (their blubber actually) from the coasts of Italy (Fossi et al., 2012). If you were wondering why this particular chemical compound was measured, it is because phthalates (DEHP & MEHP) is basically the chemical component that is used to estimate the concentrations of microplastics.
As seen in the table of the results above, 13 of the samples contained microplastic particles. Such results was key during this period of time to provide evidence that harmful chemicals are present in Mediterranean fin whales due to ingestion of microplastics. Furthermore, such amounts of plastics could potentially be due to commercial activities in the seas such as tourism, vessels and fishing. However, as we all know, plastics can be transported over great distances due to ocean currents. Thus, it is not possible to conclude that the abundance of microplastics in the area consumed by whales were solely due to human activities in the region (though it may be a huge contributor). It was predicted that such levels of chemicals in the fin whales could disrupt endocrine systems, affecting the whales’ hormones, reproduction and development (Fossi et al., 2012). However, there is still insufficient research to prove these effects. There might be other long-term effects from the exposure to the chemicals in microplastics.
Now let us look at another whale species that is a filter feeder as well. In this journal article, we will be talking about the Megaptera novaeangliae, which is a type of baleen whale . Upon studying the gastrointestinal tracts of one particular female humpback whale, 4 polymer types were identified. Let us take a look at the table of findings for the exact information about the types of polymers found.
There was a great variation in the plastics found where mesoplastics was the highest proportion, followed by microplastics and then macroplastics (Besseling et al., 2015). The different categories of plastics were ingested due to humpback whales being lunge feeders, meaning they swallow a large amount of water at one go. However, I was very disappointed with this article. It only investigated one whale, which meant that the findings could not be generalized to humpback whales in the area. Also, due to the extremely small sample size, it also meant that we could not compare the across species.
Both the articles did not investigate the effects of plastic ingestion in whales. This just highlights how limited research can be. Most research in the previous years, tend to focus on finding evidence that plastics are being consumed by whales. It is very difficult to monitor and investigate the effects due to reasons such as cost, manpower and reliable methods. We can only hope that one day someone will be able to initiate such research to provide us with a better understanding.
References
Besseling, E., Foekema, E.M., Van Franeker, J.A., Leopold, M.F., Kühn, S., Bravo Rebolledo, E.L., Heße, E., Mielke, L., IJzer, J., Kamminga, P. & Koelmans, A.A. (2015) Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae, Marine pollution bulletin, vol. 95, no. 1, pp. 248-252.
Fossi, M.C., Panti, C., Guerranti, C., Coppola, D., Giannetti, M., Marsili, L. & Minutoli, R.(2012) Are baleen whales exposed to the threat of microplastics? A case study of the Mediterranean fin whale (Balaenoptera physalus), Marine pollution bulletin, vol. 64, no. 11, pp. 2374-2379.
Enough about animals.. What about humans? What are we doing?
Check out the next post !!!