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Adélie penguins (Pygoscelis adeliae) are bioindicators for the rapidly changing Antarctic environment, making understanding their population dynamics and behavior of high research priority. However, collecting detailed population data throughout the breeding season on many colonies is difficult due to Antarctica’s harsh conditions and remote location. The colonial breeding ecology of Adélie penguins has led to the evolution of a highly vocal species with individualized calls, making them well-suited for passive acoustic monitoring (PAM) with autonomous recording. PAM units can potentially provide an easily deployable and scalable way to collect fine-scale data on population estimates and breeding phenology. Here I present a framework for using acoustic indices to monitor phenology of dense penguin colonies even under high wind conditions. I evaluate the relationship between acoustic indices such as RMS amplitude and penguin colony size between distinct breeding stages (incubation, guard, crèche, and fledge) on Torgersen and Humble Islands in the West Antarctic Peninsula with an automated pipeline implemented in R. Using PAM to interpret penguin vocalizations for population size and breeding phenology estimates could lead to the development of a real-time remote monitoring system over a large spatial footprint, revealing Adélie penguin responses to climate change.
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Long-term, landscape- and wind-driven snow conditions influence Adélie penguin colony extinctions
Abstract ContextThe interaction between topography and wind influences snow cover patterns, which can determine the distribution of species reliant on snow-free habitats. Past studies suggest snow accumulation creates suboptimal breeding habitats for Adélie penguins, leading to colony extinctions. However, evidence linking snow cover to landscape features is lacking. ObjectivesWe aimed to model landscape-driven snow cover patterns, identify long-term weather changes, and determine the impact of geomorphology and snow conditions on penguin colony persistence. MethodsWe combined remotely sensed imagery, digital surface models, and > 30 years of weather data with penguin population monitoring from 1975 to 2022 near Palmer Station, west Antarctic Peninsula. Using a multi-model approach, we identified landscape factors driving snow distribution on two islands. Historic and current penguin sub-colony perimeters were used to understand habitat selection, optimal habitat features, and factors associated with extinctions. ResultsDecadal and long-term trends in wind and snow conditions were detected. Snow accumulated on lower elevations and south-facing slopes driven by the north-northeasterly winds while Adélie penguins occupied higher elevations and more north-facing slopes. On Torgersen Island, sub-colonies on south aspects have gone extinct, and only five of the 23 historic sub-colonies remain active, containing 7% of the 1975 population. Adélie penguins will likely be extinct on this island in < 25 years. ConclusionsAdélie penguin populations are in decline throughout the west Antarctic Peninsula with multiple climate and human impacts likely driving Adélie penguins towards extinction in this region. We demonstrate precipitation has detrimental effects on penguins, an often overlooked yet crucial factor for bird studies.
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- PAR ID:
- 10581202
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Landscape Ecology
- Volume:
- 40
- Issue:
- 4
- ISSN:
- 1572-9761
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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