Collaborative Research: ULTRA-Data: Harmonizing at-sea seabird surveys at three marine LTER sites to uncover community responses from the subarctic to Antarctic

About This Grant

Use and reuse of long-term ecological data is needed for understanding how biological communities are responding to a changing world. In marine environments, key data includes large-scale patterns such as El Niño, ocean conditions such as sea surface temperature and winds, and biological data such as the distribution and abundance of food resources and marine wildlife. These core data are often collected in non-standardized ways, which makes it a challenge to compare patterns of biological response across different regions or marine ecosystems. The Long-Term Ecological Research (LTER) network provides an opportunity to make comparisons between sites as they share similarities in conceptual design and data collection procedures. In this ULTRA-Data project, a team of scientists is harmonizing ecological data from three different LTER sites representing temperate (California Current), subpolar (Northern Gulf of Alaska) and polar (Antarctic Peninsula) marine ecosystems. These three sites are influenced by global-scale processes and each provides comparable local data on ocean conditions, lower trophic level planktonic food resources (euphausiid crustaceans, also known as “krill”), and upper trophic level consumers (seabirds). The investigators are testing the idea that seabird populations and community structure are affected by local ocean conditions (habitat quality) and food resource availability, affected by larger-scale processes as observed during El Niño. Results from this study are helping scientists and marine stakeholders understand how changing ocean conditions and food availability affect marine biological communities. This study is revealing whether large-scale environmental variability is affecting disparate marine ecosystems similarly or if response mechanisms differ between regions. This research is supplying cross-ecosystem knowledge to help inform management and conservation. The scientists are also training younger researchers, including early-career scientists, graduate students, and an undergraduate intern. This project addresses a gap in our understanding of how marine biological communities respond to environmental change by conducting cross-ecosystem syntheses on the climate responses of geographically disparate but functionally analogous prey and predator communities. Seabird communities are an ideal metric for regional comparisons, as their local distribution and abundance can reflect both short-term and long-term ecosystem dynamics, and geographically unrelated seabird communities retain similar functional compositions (e.g. divers vs. fliers, planktivores vs. piscivores, etc.). By leveraging data available from three different Long-Term Ecological Research (LTER) sites, this project is testing how local ocean conditions affect seabird abundance, diversity, and community composition across the California Current Ecosystem (CCE), Northern Gulf of Alaska (NGA), and Antarctic Peninsula (PAL). These three regions represent temperate, subpolar and polar ecosystems, yet are structurally linked by large-scale Pacific climate modes including the El Niño Southern Oscillation, Pacific Decadal Oscillation, and Southern Annular Mode. The three LTER sites have collected similar long-term datasets on oceanography (hydrographic casts), prey (net-sampled euphausiids), and seabirds (at-sea visual observation surveys). Data are thus being harmonized into 30+ year datasets to investigate bottom-up linkages between climate modes, local oceanographic patterns, and local prey/predator variability. Generalized Additive Mixed Models (GAMMs) and Hierarchical Modeling of Species Communities (HMSC) are being used to test biophysical relationships, including the evaluation of temporal effects such as direct and lagged effects of climate mode variability. The integrative and cross-ecosystem framework utilizes valuable data provided by LTER sites, identifies unknown dynamics underlying ecosystem synchrony and divergence, and provides mechanistic perspectives on how regional biophysical processes contribute to productive and globally important ecosystems. 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.