The global aim to protect Earth’s biodiversity, outlined in the Kunming-Montreal Global Biodiversity Framework (GBF), includes an ambitious target of conserving at least 30% of oceans. However, a recent extensive study tracking highly mobile marine megafauna, including species critical to polar ecosystems, suggests that this 30% spatial protection alone may not be sufficient for effectively conserving these animals. The implications for the polar regions, which are undergoing rapid environmental shifts, highlight the need for a comprehensive approach that extends beyond area-based protection.
The study, which compiled an extensive dataset of 11 million geopositions from nearly 16,000 tracked individuals across 121 species, provides a global assessment of marine megafauna space use. Among the species analyzed are polar bears, penguins, and various seals, all of which are iconic groups for polar marine environments. The findings indicate that these species utilize vast areas, often traversing multiple exclusive economic zones (EEZs) and areas beyond national jurisdiction (ABNJ). Notably, polar bears spent only 0.3% of their tracked time within existing Marine Protected Areas (MPAs), and while penguins spent 23.9% of their time in MPAs, this still leaves a substantial proportion of their movements unaddressed by current protections. This suggests a limitation of current MPAs, which were predominantly designed to protect specific habitats rather than accounting for the extensive and dynamic space use of mobile marine megafauna.
Anthropogenic Pressures in Polar Environments
The study identifies several major anthropogenic threats with a global footprint, including fishing, shipping, plastic pollution, and ocean warming. These threats are pervasive, with over 96% of identified Important Marine Megafauna Areas (IMMegAs) globally exposed to plastic pollution, shipping, and warming, and approximately 75% exposed to fishing activities. In polar regions, these pressures manifest with particular urgency. Climate change, marked by rapid warming in the Arctic at approximately four times the global average, contributes to sea ice loss, directly impacting polar bear habitat and influencing the foraging access of seals, thereby affecting their survival. Shipping activity in the Arctic, which saw a 37% increase in the Polar Code area between 2013 and 2019, primarily due to fishing vessels, enhances the risk of vessel strikes for marine megafauna. Noise pollution is also a factor, potentially disturbing critical behaviors such as foraging in whales or maternal denning in polar bears due to seismic surveys. Furthermore, plastic pollution, including abandoned, lost, or discarded fishing gear (ALDFG), presents an entanglement hazard for seals in the Southern Ocean, and biofouling on vessels raises concerns about the introduction of invasive species. Grey water discharge from ships also contributes to marine pollution in these sensitive environments.
Polar MPAs: Progress and Implementation Challenges
Despite these challenges, efforts to establish MPAs in polar regions are progressing. The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), established in 1982, operates with an ecosystem-based approach and has been committed to developing a network of MPAs in the Southern Ocean since 2002. Significant achievements include the establishment of the Ross Sea Region MPA in 2016, a vast protected area of 1.55 million square kilometers, predominantly managed as a no-commercial-fishing zone to conserve diverse marine life. The South Orkney Islands South Shelf MPA, established by CCAMLR in 2009, was notable as the first MPA entirely beyond national jurisdiction. However, the establishment and effective management of polar MPAs face several hurdles. These include the sparse availability of biological data to inform conservation planning in the Antarctic, the complexities of achieving international consensus within governance bodies like CCAMLR, and the ongoing need for robust enforcement and cross-border coordination. The rapid environmental changes in polar regions also pose a challenge, as species distributions and behaviors may shift in ways that outpace static protected area designations.
Although the 30 percent protection goal is seen as a helpful target, our analysis indicates it will be insufficient to protect all important areas…
Professor David Sims, Co-Author
A Comprehensive Approach to Polar Marine Conservation
The study emphasizes that a 30% area protection target, even if optimally configured to include IMMegAs, would still leave approximately 60% of these important areas unprotected. Regarding these findings, David Sims, a co-author of the paper, stated, “We were concerned to find that these key areas overlap substantially with human-driven threats like industrialized fishing and busy shipping, which can lead to lethal collisions with many already threatened megafauna species. Although the 30 percent protection goal is seen as a helpful target, our analysis indicates it will be insufficient to protect all important areas, meaning that additional mitigation strategies are needed to reduce pressures on marine megafauna beyond areas that will be protected”.
For polar regions, this indicates that relying solely on spatial protection targets is insufficient. The research advocates for an integrated conservation strategy that couples increased area protection with direct mitigation measures to reduce anthropogenic pressures. Such measures include implementing fishing thresholds, mandating modifications to fishing gear, and developing wildlife-ship traffic separation schemes. Addressing the sources of plastic pollution and managing noise from human activities are also crucial.
While MPAs can contribute to species resilience against climate change, global efforts to reduce greenhouse gas emissions remain fundamental to mitigating ocean warming and acidification. Given that marine megafauna spend a substantial portion of their time within national EEZs, there is an opportunity for individual nations to implement immediate and effective mitigation measures within their jurisdictions. Concurrently, enhanced international cooperation and integration into agreements like the United Nations High Seas Treaty are essential for the protection of megafauna in areas beyond national jurisdiction. This treaty has made a significant step forward last week, when 19 additional countries had ratified the treaty, bringing it to 50 out of 60 needed to come into effect.
Overall, a systematic conservation planning framework that considers all facets of marine biodiversity and incorporates principles of environmental justice will be vital in achieving effective conservation outcomes for marine megafauna, both in the polar regions as well as in the rest of the world.
Link to the study: Sequeira et al (2025) Science 388 (6751) Global tracking of marine megafauna space use reveals how to achieve conservation targets