Chinstrap penguin (Pygoscelis Antarcticus) foraging habitat model for the South Orkney Islands

• Main Author: Fabrizio Manco
• Format: Thesis
• Language: unknown
• Published: 2023
• Subjects: Pygoscelis antarcticus; foraging habitat modelling; tracking data; GIS; machine learning; South Orkney Islands; Southern Ocean; Antarc*; Antarctica; antarcticus; Chinstrap penguin
• Online Access: https://figshare.com/articles/thesis/Chinstrap_penguin_Pygoscelis_Antarcticus_foraging_habitat_model_for_the_South_Orkney_Islands/23761623

The Southern Ocean is under several threats due to global human activities but also to local resource exploitation. The chinstrap penguin (Pygoscelis antarcticus) is a key species in the Antarctica marine food web. Along with other predators, it has been impacted, albeit mostly indirectly, by harvesting in the past. The recent overlap and competition with krill fisheries necessitates constant attention and a better understanding of how this species utilises its environment; this can be achieved partly by developing a model of their foraging habitat. In this context, birds from two different colonies in the South Orkney Islands have been tracked with GPS devices and TDR loggers during the breeding season. The resulting dataset allowed me to create a three dimensional representation of their foraging trips. The different methodological approaches I designed allowed me to assess how the birds use their environment across space and time. By studying changes in movements, I was able to detect when the birds were foraging. Linking these foraging locations with explanatory environmental variables, I was then able to develop a foraging habitat model for this species around the South Orkney Islands. The model went through a series of performance measurements and validation processes. The final resulting map offers a picture of where chinstrap penguins forage from their colonies. The range of foraging, the density of birds, the hotspot areas, the depths of foraging and how these parameters change with time can be used to support policies and management targets. I believe these results can also be useful for further studies.