Seaspiracy from the Perspective of a Conservation Biologist

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Seaspiracy from the Perspective of a Conservation Biologist

The recent documentary, Seaspiracy, made by British filmmaker Ali Tabrizi has quickly risen to fame, placing on Netflix’s “Top 10” and receiving lots of praise; however, it has also been faced controversy due to its dramatic cinematography and sensationalised statements. The documentary questions the notion of sustainable fisheries and aquaculture, and discusses slave labour and human rights issues linked to the fishing industry. As a conservation biologist myself, many of the bold claims, misconstrued statistics, and the use of outdated and redacted research did not sit right with me. Whilst the documentary is right to highlight the impacts of industrialised fishing on marine biodiversity and human rights, the execution of this is done poorly, presenting a bias and misleading narrative. The purpose of this article is not to bash the documentary- plenty of others have done that already- instead, I’m going to delve deeper into the issues discussed in Seaspiracy and shed some light on the misinformation shared by the documentary.

46% of Marine Plastics Are Fishing Nets

Plastic pollution has become increasingly ubiquitous in both marine and terrestrial habitats. Plastics breakdown down into small particles known as microplastics and are washed into our river systems and oceans, where they are then consumed by marine life, such as whales, marine birds, and zooplankton (Wilcox et al., 2015, Cole et al., 2013, Im et al., 2020).  When microplastics are consumed they make their way up the food chain through a process known as bioaccumulation (Goswami et al., 2020). Seaspiracy also discusses the growing issue of microplastics and goes on to state that 46% of the plastic in the oceans is from discarded fishing nets, and whilst this is somewhat correct, it is also a little misleading. This statistic originates from a paper published in 2018, assessing the plastic pollution of the Great Pacific Garbage Patch. Results indicated that mega-plastics (>50cm), such as fishing nets, represented 46% of the Great Pacific Garbage Patch when mass is considered, however when number of pieces was considered microplastics were the most prevalent, representing 94% of the Great Pacific Garbage Patch (Lebreton et al., 2018).


Empty Oceans by 2048

Among the many pervasive anthropogenic threats to marine species, such as plastic pollution, water quality degradation, and climate change, overfishing has frequently been highlighted as a leading contributor in the decline of marine biodiversity (Sadovy de Mitcheson et al., 2020, Jackson et al., 2001). Overfishing and the removal of apex predators, such as tuna and sharks, can cause the entire ecosystem to collapse. Seaspiracy does successfully highlight this issue and states that if we continue fishing at our current rate the oceans will be empty by 2048 (Worm et al., 2006). Nevertheless, this statement is based off misconstrued research (Worm et al., 2006) and has since been refuted (Worm et al., 2009, Hilborn et al., 2020). Compiled estimates of the status of global fish stocks from all the available scientific assessments, comprising of roughly 50% of the world’s harvest, indicate that fish stocks are increasing on average (Hilborn et al., 2020). Despite the improvement of some managed stocks, overfishing is still a prevalent threat to marine species and shouldn’t be overlooked due to increasing trends (Cashion et al., 2019, Ricard et al., 2012, Dulvy et al., 2014, Yan et al., 2021). 

40% of the Global Catch is Discarded as Bycatch

Bycatch is “the total catch of non-target animals.” (FAO, 2020). This definition is the wildly accepted. Bycatch can be used as an indicator of the impact fisheries are having on the ecosystem, providing valuable data that can be used to improve fishery sustainability. An important nuance to consider is that bycatch is either discarded or used, with the latter being generally approved as sustainable, provided the non-targeted species is not a threatened species (FAO, 2020). Seaspiracy states that 40% of the global catch is discarded as bycatch. This statistic originates from research proposing to redefine bycatch to include all catch from unmanaged fisheries. By following this definition, the bycatch results from this study were grossly inflated (Davies et al., 2009). This definition has since been not accepted, and more recent studies indicate that only 10% of bycatch is discarded and wasted (Zeller et al., 2017, FAO, 2020). Seaspiracy goes on to state that in the USA, 250,000 sea turtles are killed as a result of bycatch. This statistic comes from a study published in 2004 (Lewison et al., 2004), however more recent research shows that this sea turtle deaths as a result of bycatch and the fishery industry have decreased by 60% and 94%, respectively, following improved mitigation measures (Finkbeiner et al., 2011).

Sustainable Fishing Does Not Exist

The term Maximum Sustainable Yield (MSY) is frequently used when discussing sustainable fisheries. MSY is the maximum catch that can be sustainably harvested from a stock. Seaspiracy paints a picture of all fisheries being unsustainable and corrupt, however a fisheries assessment conducted by the FAO in 2017 found that only 34.2% of fish stocks were classified as overfished. The same 2017 assessment estimated that of the assessed stocks in the Western Indian Ocean, 66.7% were fished within the biologically sustainable levels, whilst 33.3% were considered unsustainable, (FAO, 2020). Despite progress in some fisheries, the number of stocks sustainably fished has decreased from 90% in 1974 to 65.8% in 2017 (FAO, 2020). Unequal fisheries management between regions highlight the necessity to replicate and re-adapt policies to ensure fisheries are sustainable and not overfished (FAO, 2020). Stocks that are sustainably managed have proven to be more productive (Hilborn et al., 2020). Intensively managed fisheries have been successful at decreasing fishing pressure and increasing stock biomass (FAO, 2020). For example, in the 1980s the Patagonian toothfish became very popular after being rebranded for menus as “Chilean sea bass”, and demand and price skyrocketed. This put large amounts of pressure on stocks. Because of how lucrative fishing Patagonian toothfish was, by the late 1990s there were more illegal catches than legal, and stocks were on the verge of collapse. The Coalition of Legal Toothfish Operators was established in 2003 to eliminate illegal toothfish fishing and promote sustainable fisheries, and Patagonian toothfish stocks have since been able to recover (Marine Stewardship Council, 2018).

People Should Stop Eating Fish

Seaspiracy’s take away point from the documentary was to stop eating fish all together. While this is an admirable sentiment, it only favours privileged groups that can afford to source their protein from elsewhere. 3.3 billion people are dependent on fish as 20% of their average per capita intake of animal-based protein, and 59.5 million people work within the primary fishing sector. Fish and fish products play an essential role in national, regional, and global food security, and are therefore essential for transforming food systems and eliminating world hunger (FAO, 2020).


In conclusion…

While I, and many other conservationists and marine biologists, may disagree with the misinformation spread by Seaspiracy, I do also acknowledge that there are many ongoing issues with the fishing industry that need to be addressed with greater urgency. Seaspiracy has brought these issues to the attention of Netflix’s massive 200 million viewership, which is fantastic. However, the documentary’s take home message that sustainable fisheries do not exist and people should stop eating fish all together, does not help the cause. Instead, we should be demanding legislative and policy changes and better law enforcement.

Seaspiracy - Netflix

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