Citation: Handley, J., Rouyer, M. M., Pearmain, E. J., Warwick-Evans, V., Teschke, K., Hinke, J. T., … & Dias, M. P. (2021). Marine Important Bird and Biodiversity Areas for Penguins in Antarctica, Targets for Conservation Action. Frontiers in Marine Science, 7, 1190. https://doi.org/10.3389/fmars.2020.602972
Marine ecosystems are often vast and in faraway places, but did you know that despite this, they are easily impacted by people and climate change? To protect marine ecosystems from the impacts of people and climate change, Marine Protected Areas (MPAs) are often created. In fact, many scientists believe that preserving 10% or more of coastal and marine areas will be needed to effectively protect marine ecosystems. This may sound like a surefire way to protect these ecosystems, but now we are realizing that focusing just on protecting a certain percentage of the ecosystem isn’t enough. Specific parts of the ecosystem are more important, ecologically speaking, than others. Therefore, focusing on protecting high-quality and ecologically important habitat, as well as an overall percentage, is likely to be more effective at protecting marine ecosystems.
You may be wondering how we would decide where to focus our conservation efforts since marine ecosystems are so big. We can turn to the species that live within those ecosystems to help us out. For example, seabirds aren’t just cool animals see, but can also help us decide exactly where is best to focus conservation efforts for an entire marine ecosystem. This is because they are an indicator species; the size and health of their populations can indicate to us the overall health of their ecosystem. Penguin species found in Antarctica are indicator species. They feed on krill, which is an important part of the food chain for all species living in Antarctica, and they live only where sea ice exists. If their populations are small, it is likely because of a lack of food which indicates overfishing, and/or because of a lack of sea ice, indicating warming temperatures due to climate change.
Antarctic penguins consume Antarctic krill, like the one pictured above. Source: WikiCommons
The Southern Ocean and other seas around Antarctica are especially threatened by climate change and fishing. To help protect these water bodies, the Commission for the Conservation of Antarctic Marine Living Resources has created two MPAs and are planning at least three more. Penguins are a good species to protect using MPAs since can only travel a certain distance from home during their breeding period to feed their children daily. If we know that a healthy penguin population indicates a healthy marine ecosystem (e.g. the presence of a healthy food chain and plenty of sea ice for habitat), focusing on protecting the areas most important to penguins is a good way to protect as many species as possible within these marine ecosystems.
To help with planning the proposed MPAs in Antarctica, an international group of researchers conducted a study to identify marine Important Bird and Biodiversity Areas (IBAs) for breeding and conserving penguins in Antarctica. The researchers used four penguin species: Adélie, Chinstrap, Gentoo, and Emperor Penguins. All of these species either breed in Antarctica or are found only in Antarctica. They also all rely on krill as a big part of or all of their dietary needs. After deciding which species to focus on, the researchers determined which specific locations in Antarctica are used by a large proportion of these species, which they identified as IBAs. They used estimated populations sizes published in other studies and determined important areas during breeding season based on population size and the foraging distance from their typical colony location during breeding season. After determining the IBAs for each species, the researchers combined them into overall important areas in Antarctica. They then compared their IBAs to the proposed MPAs and to the location of krill fisheries.
The researchers identified a total of 63 IBAs and found that between the current and proposed MPAs, over 80% of their identified IBAs are protected. However, this overlap of IBAs and MPAs mainly occurs for the Adélie and Emperor Penguins; Chinstrap and Gentoo Penguin IBAs were not accounted for as much in the MPAs. The current MPAs only protect between 0-30% of the identified IBAs, depending on the species, meaning that the proposed MPAs are needed. Based on these results, the researchers suggest that the proposed MPAs focus most on the areas that contain IBAs common to all four penguin species. These are the areas likely to be the most ecologically significant for the largest number of marine species, including whales, seals, and petrels.
Killer whales and a seal in Antarctica. Like the penguins in the study, these species also depend on a healthy krill population. Source: WikiCommons
In their comparison to the krill fishery locations, the researchers found that significantly more krill fishing occurs within the IBAs than outside of them, which means that incorporating the IBAs, especially the ones most fished, into future MPAs will help protect the Antarctic food chain and the penguins and other species that rely on it. By comparing their IBAs to the current and proposed MPAs and known krill fisheries, the researchers have shown that it is important to focus on protecting the parts of the ecosystem that are ecologically important, and that indicator species can be a tool to help us do this. Protecting the places most important to the indicator species is likely to protect the ecosystem as a whole because it ensures that the ecosystem is healthy enough and has the resources to support the species that live there. This type of conservation approach could be successfully applied to other ecosystems as well, making our conservation efforts more likely to succeed.