The Expedition

The original objective of the work was to investigate an area of the Arctic Pacific from which few data had been published by previous Russian expeditions. Due to current constraints preventing work near Russia, we now propose to move the planned research from the western to the eastern Aleutian Trench to the EEZ of the United States.

We will analyze seafloor topography (bathymetry), biogeochemistry, and microbiology, and analyze the systematic composition, species diversity, biogeography, and evolution of fauna of all size classes from protists to meio-, macro-, and megafauna in the Aleutian Trench. We will therefore expand the sampling area to the east and provide samples for molecular approaches.

To best characterize the study area, we will first map the seafloor with the multibeam echo sounder and then conduct biogeochemical and microbiological analyses with a free-fall lander system. To better understand the range and biogeography of the organisms of the Aleutian Trench, we plan to collect animals from the water column and seafloor and, if possible, identify them to species.

We plan to compare our new biological samples from the eastern Aleutian Trench with the biological samples from the sampling areas of the KuramBio I and II expeditions and from previous Russian expeditions. We plan integrative taxonomic work on key species that may be critical to understanding and clarifying relationships. In addition, we will use standard molecular techniques as the basis for phylogeographic surveys and connectivity studies, as well as state-of-the-art genomic techniques to integrate the data into in-depth phylogenetic analyses as well. We rely on freshly frozen material from new samples. In shallow bathyal waters, faunal links between passages to the Bering Sea have also been demonstrated.

We plan to work in both the Bering Sea (at least 2 stations) and the East Aleutian Trench at abyssal and hadal depths. This will allow both a comparison of species connectivity and biogeography between samples previously collected in the Kuril-Kamchatka Trench and the new samples in the East Aleutian Trench and, using the Bering Sea stations, an estimate of migrations into and out of the Bering Sea to the Arctic.