Florida Institute of Technology
Supporting Stations: RV/IB Nathaniel B. Palmer
Research Locations: Marguerite Bay
The Antarctic benthos, living at the lower thermal limit to marine life, serves as a natural laboratory for understanding the impacts of climate change on marine systems in general. The endemic marine fauna of Antarctica currently lacks the durophagous (skeleton-breaking) predators that structure benthic food webs in nearshore habitats at tropical, temperate and Arctic latitudes. A cooling trend beginning about 41 million years ago in the Eocene eliminated modern bony fish, crabs, lobsters, and other benthic walking forms, and almost all modern sharks, rays, and skates from Antarctic waters. Since that time, the benthos has evolved toward an archaic, quasi-Paleozoic community structure in the absence of that upper trophic level. Now, climate change appears destined to reconfigure subtidal marine communities in Antarctica. Rapid warming of the Southern Ocean is removing physiological barriers to the reinvasion of durophagous predators, and the larval and adult stages of crabs are reappearing. The goal of this study is to assess the status, viability and ecological impacts of populations of potentially invading, predatory king crabs in the Bellingshausen Sea. The data will provide a baseline for large-scale, long-term monitoring programs to track benthic assemblages in Antarctica over the coming decades of climate change.
Field Season Overview:
On this cruise field team members will use a towed-camera vehicle to record benthic transects on the continental shelf at various depths. The quality of these images will be high enough to identify, size, and enumerate king crabs and any other decapods to the species level. Once crabs are located, the science party will deploy five bottom lines with 10 baited traps each. Upon retrieval, each living crab will be sexed and measured. After the crabs are inspected externally for parasites and, for females, reproductive state, their stomachs will be removed for dietary analysis. Following removal of the stomachs, the crabs will be frozen and shipped to the home institution for further analysis.
Deploying Team Members: