Penguin gut microbiomes are potential indicators of Antarctic ecosystems
Posted on October 30, 2024 by Dr Wen Chyin Yew
Dr Wen Chyin Yew takes us behind the scenes of their latest publication 'Seasonal variation in the stomach microbiota of two sympatrically breeding Pygoscelis penguin species at Signy Island, South Orkney Islands' published in Microbiology.
Hello, I’m Wen Yew, a senior post-doctoral research assistant in Professor Darren Smith’s laboratory at Northumbria University, Newcastle upon Tyne, UK. This study is part of my PhD research at University of Malaya, Malaysia – analysing bacterial community compositions in Adélie and chinstrap penguin stomach regurgitates, guano and rookery soils on Signy Island, Antarctica.
The population and distribution changes in Antarctic penguins have been related to changes in regional climate (in particular those affecting sea ice extent and foraging environment) and the marine ecosystem (e.g. food resources) (Forcada and Trathan, 2009). These changes may, in turn, influence the development of penguin gut microbiomes (e.g. through the incorporation of different marine and prey-associated bacteria) and subsequently influence fitness of the host birds and their chicks (Dewar et al., 2017). As penguins feed at sea, breed moult on land and input nutrients to terrestrial ecosystems through their faecal deposits (Chong et al., 2009), their gut microbes may also be transferred in the deposited guano, and thereby contribute to the microbial community developing in the surrounding terrestrial environment. However, little research is available on the stability or variability of penguin gut microbiomes over time.
On Signy Island (British Antarctic Territory), sympatrically breeding Adélie (Pygoscelis adeliae) and chinstrap (Pygoscelis antarctica) penguins share overlapping foraging areas and exploit the same food resources, and thus they served as a good model for my research. I was awarded a postgraduate scholarship by the Higher Education Ministry of Malaysia, as well as a berth support to Antarctica and two fellowships by the Sultan Mizan Antarctic Research Foundation to complete this international collaborative research with British Antarctic Survey and Northumbria University. The first aim in this research was to gain an understanding of the bacterial communities in penguin stomachs and to assess the variability between different individuals and different penguin species. We found stomach microbiota variability can occur in different species of penguins that consumed 100% Antarctic krill under a similar foraging and breeding environmental condition (Yew et al., 2017). The second aim was to identify correlations between the bacterial communities in penguin stomachs and those in their faecal deposits and the surrounding soils in the vicinity of their colonies. We observed very little in situ contribution of microbes in penguin stomach and deposited materials to the surrounding terrestrial soil microbial ecosystem (Yew et al., 2018).
In our most recent study, we investigated if the variability in penguin stomach microbiota persists across different austral summer penguin breeding seasons. We discovered distinct seasonal shifts in stomach microbiota in two different penguin species that share similar foraging patterns and environmental conditions. Our finding suggests a nuanced interplay between diet, environmental factors and microbial communities, and highlights the influence of seasonal changes on penguin gut microbiomes. In addition, we also identified specific bacterial taxa that are associated with diet preferences, and this unveils the possibility of penguin gut microbes as potential biomarkers and ecological indicators for monitoring environmental changes in Antarctica.
I believe that penguin gut microbiomes are vulnerable to regional climate change and important to the Antarctic ecosystems. In future, my research interests focus on how shifts in regional temperature and ice coverage might alter the gut microbiomes of Antarctic penguins and further effects on the host birds’ health. Understanding these interactions is key to conserving fragile polar ecosystems, especially as climate change accelerates. On the other hand, discovery of unique microbial strains from this extreme environment offers potential biomarkers, ecological indicators and applications leading to innovations in medicine, agriculture and environmental sciences.
Dr Wen Chyin Yew was also the winner of our AC25 prize draw, winning free registration for Annual Conference 2025.