USAP-DC

Non-technical abstract Adélie penguins are an early indicator of change in Antarctica. One study population in the Ross Sea is stable or growing, while another near the Antarctic Peninsula is declining quickly, even though both face a warming climate. This project asks a question that matters for conservation and for our broader understanding of how species adapt to environmental change: what allows some penguin populations to cope while others do not? Researchers will follow penguins from the two regions through the parts of their lives that are hardest to observe. Small tracking tags placed on young penguins just before they leave their colonies will reveal where they travel on their first trips to sea and how many survive. Recording devices retrieved from adult penguins will show where and when they molt their feathers and how deep and how often they dive for food through the winter. Blood samples will map how penguins from the two regions are related ancestrally and whether the populations mix regularly. Together these measurements show how each population feeds, travels, and survives, and whether differences in behavior help explain why the two are heading in opposite directions, informing how Antarctic wildlife is understood and protected as the region changes. The tracking and recording devices collect temperature and other ocean data from a remote region during the season when it is most difficult to study, adding to the information available for understanding and managing the Southern Ocean. The project also trains the next generation of polar scientists, supporting a doctoral student and a field apprentice, and it continues long-term monitoring that reaches back decades. Education and public outreach will include "Live From the Penguins" video calls and updates on penguin colony and breeding behavior through the PenguinScience.com website and social media. Technical abstract Adélie penguins are a key Antarctic mesopredator and a useful model for studying the limits of biological adaptation under rapid environmental change. This two-year project unites two of the longest-running United States Adélie penguin research programs (a stable-to-increasing population in the Ross Sea and a declining population near Palmer Station on the western Antarctic Peninsula) as a natural experiment in adaptive capacity. The work centers on three traits measurable from one intensive field season combined with existing biologging and multi-decadal monitoring data. Satellite-linked transmitters deployed on fledglings before colony departure in both regions will quantify juvenile dispersal routes, habitat use, and at-sea survival. Archival geolocating dive recorders recovered from adults will characterize molt timing and location (sea ice versus land). The same instruments yield year-long dive, light, and temperature profiles, allowing foraging performance and environmental thresholds to be compared across contrasting breeding and wintering regions. A genetic component addresses population structure: whether mitochondrial lineages sort by colony, how genetically contained the Ross Sea population is, and how prevalent the Ross Sea lineage is in the under-sampled Palmer region. Together these provide a framework against which trait differences can be interpreted. A second field season supports instrument retrieval and continued long-term monitoring. The project trains one doctoral student and one field apprentice and extends datasets that reach back decades in both regions. This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.

Person	Role
Ballard, Grant	Investigator and contact
Schmidt, Annie	Co-Investigator
Lescroel, Amelie	Co-Investigator
Cimino, Megan	Investigator
Varsani, Arvind	Investigator

Antarctic Organisms and Ecosystems	Award # 2535124
Antarctic Organisms and Ecosystems	Award # 2535122
Antarctic Organisms and Ecosystems	Award # 2535121
Antarctic Organisms and Ecosystems	Award # 2535120

USAP-2535120_1

Deployment	Type
Cape Crozier	field camp
Cape Royds	field camp
McMurdo Station	general deployment
Palmer Station	general deployment

None in the Database