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Scientists call partially protected areas the “Red Herrings” of marine conservation

New Studies Explore the Effectiveness, or rather Ineffectiveness, of Partially Protected Marine Areas

By Eleri Griffiths, Blue Parks Intern


Marine protected areas (MPAs) are vital tools for protecting, conserving, and restoring marine ecosystems. Leading experts in marine science and conservation across the globe are advocating for protection of 30% of the global ocean by 2030 [1]; yet currently, only about 7% of the ocean is protected. In addition, the level of protection afforded by an MPA, based on the strength of its regulations, varies widely between MPAs. Fully protected areas (FPAs), which do not allow any extractive activities, cover less than 2% of the global ocean [2]. Meanwhile, partially protected areas (PPAs), which allow some fishing, make up 69% of existing MPA coverage. Two new studies of Australian MPAs evaluate the effectiveness of PPAs compared to FPAs and highlight the conservation value of full protection [3][4].

Turnbull et al. (2021) studied 56 sites along Australia’s coastline (19 in FPAs, 18 in PPAs, and 19 in unprotected areas) to assess and compare their social and ecological attributes. The authors used Reef Life Survey data, surveys and interviews to analyze the marine communities and the human uses, perceptions, and values surrounding them [3]. The results showed that FPAs had significantly higher levels of species richness, abundance, and biomass than PPAs. FPAs were also more positively perceived, more highly valued, and their regulations better understood than PPAs. In fact, the study found that PPAs offered no advantage relative to unprotected areas in terms of fish abundance as well as human perceptions of attractiveness, quality of marine life, or level of understanding. To put this in perspective, 40% of people surveyed in PPAs thought they were in an FPA, 23% thought they were in an unprotected area, and about 15% said they didn’t know. In comparison, 79% of people surveyed in FPAs correctly identified the level of protection [3]. From these results, it seems that FPAs, with clearer restrictions on fishing, are more effective in achieving conservation goals.

So why in the world do we have so many PPAs? The study highlights several contributing factors. One is the socioeconomics and politics of regulating human use. Prohibiting extractive activities may spark controversy with industry interests and not seem politically viable, while doing nothing costs the support of environmental advocates. Cost is another factor that might also be used to justify a PPA over an FPA. Significant financial resources are required to design, plan, implement, manage, and enforce MPAs, and it seems logical that full protection would use more resources than partial protection. However, the study asserts that this is a misconception and PPAs offer no clear financial advantage over FPAs; so actually, using these resources to provide a higher level of protection to important marine ecosystems makes even more sense [3].

There are circumstances in which PPAs can be effective, like when they are a part of a wider management framework that places them adjacent to FPAs, or when they allow lower-impact traditional fishing practices. Another recent, smaller-scale study (Hall et al. 2021) provides evidence of the effectiveness of complementary PPAs and FPAs in the Great Barrier Reef Marine Park. Although reductions in target species abundance were found in the PPAs compared to the adjacent FPAs, these species were still found in moderate numbers, showing, the authors argue, that PPAs provide intermediate conservation value and can allow for conservative, sustainable fishing practices, especially when PPAs put stringent limits on fishing activities and are located next to FPAs.

However, it is important to emphasize that the results of this study are relevant only to adjacent PPAs and FPAs within a single well-managed MPA. On a larger scale, and when stand-alone PPAs were included, Turnbull et al. argue that PPAs are “red herrings,” posing as an attractive compromise but in reality using valuable conservation resources without providing real benefits [3]. In both studies, it seems clear that FPAs are invaluable to effective marine conservation.

Effective MPAs have higher species richness, abundance, and biomass because the strong restrictions conserve marine habitats and prevent species from being targeted by humans. Open areas that have no restrictions can be extremely destructive to marine life. PPAs struggle to bridge this gap and often fall short of offering the level of protection that marine ecosystems need to stay vibrant and healthy. Source: Ocean Conservancy

So, what does this mean, as across the globe we look for the solution to better marine protection? It means we clearly need to focus on creating more well-managed, fully and highly protected MPAs and strengthening existing PPAs to reach full / high protection. We must use PPAs to supplement fully and highly protected areas, rather than as a standalone solution in most cases. This is where organizations like Marine Conservation Institute and our Blue Parks initiative come in. By awarding MPAs that meet the rigorous science-based standards for effective marine protection, Blue Parks incentivizes implementing MPAs that uphold high quality levels of protection. Blue Park awards are beneficial to the local communities, governments, and NGOs involved in these successful MPAs because not only do they celebrate the hard work of everyone involved, they also attract tourists, investors, and support, and they connect MPA efforts around the world, helping to standardize what effective protection looks like. And with another year of outstanding Blue Parks nominees, the goal of 30×30 comes a little closer into reach.

[1] O’Leary et al. (2019) 30X30: A blueprint for ocean protection. Greenpeace report, 94 pp.

[2] Marine Conservation Institute, 2021. “The Marine Protection Atlas”. Retrieved April 2021 from https://mpatlas.org.

[3] Turnbull et al. 2021. Evaluating the social and ecological effectiveness of partially protected marine areas. Conservation Biology 0: 1-12.

[4] Hall et al. 2021. Partially protected areas as a management tool on inshore reefs. Rev Fish Biol Fisheries.