The project focuses on assessing the conservation status of penguins in the region, which are considered sentinel species and bioindicators of the health of marine ecosystems.
Penguins, considered symbols of the marine ecosystems of the southern hemisphere, play a fundamental role not only as emblematic species, but also as essential indicators of environmental health. Recent studies have shed light on these birds' multifaceted role as ambassadors for conservation efforts in the face of various stressors affecting their habitats and as bioindicators of environmental pollution, especially mercury contamination.
These studies are part of an international initiative led by the Institut de Ciències del Mar (ICM-CSIC) in Barcelona, in collaboration with scientists from France, United Kingdom, Australia and New Zealand. The study takes advantage of the extensive datasets of the Global Biodiversity Information Facility (GBIF) to perform a pioneering spatial analysis of penguin distribution and the multiple stressors they face.
The results are reported in a study recently published in the prestigious Global Change Biology journal. The study covers all 18-penguin species worldwide and reveals fundamental data on the uneven spatial distribution of stressors - including climate-driven environmental changes at sea, industrial fisheries and human disturbances on land - within the ranges of the different species.
"Certain regions, such as the coast of Peru, the Patagonian shelf, the Benguela upwelling region and the coasts of Australia and New Zealand, are significantly affected by multiple stress factors, which put different pressures on penguin populations", contextualizes ICM-CSIC PhD student Míriam Gimeno, who led the study together with her thesis supervisors Dr Marta Coll and Dr Francisco Ramírez.
The study shows that the Humboldt penguin (Spheniscus humboldti), the African penguin (Spheniscus demersus) and the chinstrap penguin (Pygoscelis antarcticus) stand out as the species most at risk to these stress factors, underlining the urgent need for specific conservation strategies for each of these species.
This is the first work to spatially assess the main impacts faced by the global penguin community, identifying changes in food availability due to the impact of these stressors on the penguin community.
On the other hand, the study highlights that the different stressors do not act independently, but often interact synergistically. Therefore, studies such as this one aimed at assessing the accumulation of multiple impacts are particularly relevant in the current context of global change.
"The objectives of this work are in line with those of large organizations such as the International Union for Conservation of Nature (IUCN) when it comes to raising major issues on penguin conservation today and in the future," added Associate Professor André Chiaradia, from Phillip Island Nature Parks (Australia) and Professor Phil Seddon, from the University of Otago (New Zealand). Both are members of the IUCN penguin expert group and participated in the study.
Penguins, bioindicators of pollution
In parallel, another study recently published in Environmental Pollution and led by the same ICM-CSIC research team highlights the important role of penguins as bioindicators of the state of mercury contamination of marine ecosystems in the southern hemisphere.
The results of the study show how penguins allow us to obtain large-scale information on the state of pollution in the oceans; which helps us to identify particularly polluted areas; as well as to define research targets for the future.
"Mercury is a particularly persistent and widely distributed pollutant in the marine environment. However, we observed that areas such as Australia, Tierra del Fuego (Argentina) and the Indian Ocean are particularly affected by this type of pollution", highlights Dr. Carola Sanpera, from the University of Barcelona and co-author of the study.
"In the context of assessing the effectiveness of the Minamata Convention on Mercury Pollution, it is urgent and important to be able to assess pollution in the global ocean. However, the data available to us are often fragmentary and refer to a specific species or area," explains Dr Paco Bustamante, professor at the University of La Rochelle (France), who also participated as a co-author of the study.
Against this backdrop, both studies, framed within the SOSPEN, SEASentinels and PROOCEANS projects, funded by the State Research Agency (AEI), underline the critical need for further research and international collaboration; identifying knowledge gaps in species such as Fiordland, Snares, upright-crested, royal, yellow-eyed and Galapagos penguins, as well as in geographic regions such as the Galapagos Islands, South Africa and the coast of Chile.
Assessing the distribution of the multiple impacts that may affect these and many other marine species is essential to identify particularly threatened species and populations that require special attention. This would allow management and mitigation measures to be focused where urgent and necessary. The experts therefore call for coordinated data acquisition and sharing efforts, which are essential to comprehensively understand and address the threats that multiple stressors pose to these vulnerable species and their habitats.
All in all, these findings not only reinforce the role of penguins as sentinels of environmental change, but also highlight the urgency for concerted global action to preserve their habitats and mitigate the impacts of overfishing and pollution, ensuring the continued well-being of these iconic seabirds and the marine ecosystems they inhabit.