Our Submerged Past: Exploring Inundated Late Pleistocene (10,600 – 17,000 years ago) Caves in Southeast Alaska with Sunfish

Overview

From May 24-June 10, 2023, a team of Indigenous Alaskans, local community members, and scientists explored the continental shelf west of Prince of Wales Island in southeast Alaska, as the second part of a multi-year project. Their goal was to locate and explore submerged caves and rock shelters that would have been accessible to early inhabitants of the region.

The team searched for submerged caves and rock shelter entrances using the SUNFISH® autonomous underwater vehicle (AUV) from aboard Fishing Vessel Showtime. This second part of the expedition project to explore southeast Alaska within the United States Exclusive Economic Zone followed an initial survey in May-June 2022 to identify target areas of interest for further exploration. Since the location of these submerged caves and rock shelters on the continental shelf places them closer to the coastlines of late Pleistocene Alaska (10,600 – 17,000 years ago), the project had the potential to transform our understanding of how and when people migrated to the Americas.

In 2023, the expedition team returned to areas identified in side-scan sonar last year to confirm whether features in the data represent true cave entrances or rock shelters. The team used the SUNFISH® vehicle to investigate these features and gathered detailed multibeam and camera data that was processed into maps. After reviewing this detailed data, an experienced dive team used the maps to perform sampling of targeted sites, bringing back sediment that was analyzed by the archaeology team.

New caves identified during the project were named by the local southeast Alaskan communities to honor the significance of these sites to their heritage. Archaeological locations were recorded and submitted to the Alaska Office of History and Archaeology. The data generated by this project was archived at the data warehouse of NOAA’s National Centers for Environmental Information.

Our Submerged Past adopted what is known as “Two-Eyed Seeing” as the guiding principle of operation to bring together western and Indigenous knowledge and ways of knowing. Members of the team represent local Indigenous knowledge including Haida and Tlingit, local fishing and community knowledge, and western science. Together, the team worked to build a better understanding of our past.