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

May 15-June 4, 2022 / May 24-June 10, 2023

Year 1 Expedition Update

From May 15-June 4, a team of Indigenous Alaskans, local community members, and scientists completed the first year of fieldwork for the Our Submerged Past expedition, exploring the continental shelf west of Prince of Wales Island in southeast Alaska. Their goal was to locate submerged cave and rock shelter entrances that can be further explored in 2023, during the second year of the expedition.

We have just returned from three weeks of surveying in southeast Alaska. We had amazing weather. The image below is of Cape Addington’s Roller Bay on the southwest side of Noyes Island. The morning fog would evaporate to reveal a beautiful flat ocean, though, on this day, the ocean swell off the Pacific made things more difficult.

Southeast Noyes Island from the back of the F/V Showtime on a foggy morning during the first year of fieldwork for the Our Submerged Past expedition.
Southeast Noyes Island from the back of the F/V Showtime on a foggy morning during the first year of fieldwork for the Our Submerged Past expedition. Image courtesy of Our Submerged Past. Download largest version (jpg, 3.8 MB).
Foggy morning in Veta Bay on the northwest side of Baker Island with shore caves visible.
Foggy morning in Veta Bay on the northwest side of Baker Island with shore caves visible. Image courtesy of Our Submerged Past. Download largest version (jpg, 4.9 MB).

We worked from the north end of Prince of Wales Island (Protection Head) down to Dall Island in the south (Divers’ Bay). Our local teammates, Captain Roby Medina and Brant Baxter, knew of numerous intertidal caves along the shore and many more kept the team engaged. The strong tides and difficulty anchoring will make many of them challenging to access (see photo from Veta Bay on the northwest side of Baker Island and the cave at Diver Island on the northwest side of Dall Island). We had some technical issues with our sonar and remotely operated vehicle (ROV), but were able to resolve them as they arose. At 21 different locations (see the map), we collected over 200 gigabytes (GB) of sidescan sonar data and recorded video and pictures of the seafloor totaling over 100 GB.

Caves on the shoreline of Divers Island off the west coast of Dall Island, seen during the first year of fieldwork for the Our Submerged Past expedition.
Caves on the shoreline of Divers Island off the west coast of Dall Island, seen during the first year of fieldwork for the Our Submerged Past expedition. Image courtesy of Our Submerged Past. Download largest version (jpg, 2.5 MB).

We gained valuable understanding about the seafloor and submerged landscapes. These data provided numerous locations to explore with autonomous underwater vehicle Sunfish in 2023, as well as some potential shell middens–locations where past people lived and remains of shellfish accumulated that regularly include high preservation potential for archaeological artifacts.

Exploring with the ROV also helped us identify some interesting objects on the seafloor. While trying to relocate the wreck of the Restless, a 31-foot yawl that wrecked in the area in 1910, we found a rifle (image below). There is no indication that the rifle is associated with the wreck, which we did not relocate, unfortunately.

Rifle located on the seafloor in Shakan Bay at over 46 meters (151 feet) depth, discovered during the first year of the Our Submerged Past expedition.
Rifle located on the seafloor in Shakan Bay at over 46 meters (151 feet) depth, discovered during the first year of the Our Submerged Past expedition. Image courtesy of Our Submerged Past. Download largest version (jpg, 531 KB).

The time spent in this unique area of Alaska was hard work but also an amazing experience. Everyone is now home and the team is excited to review our sonar data and fine-tune our targets for the field campaign next year, where we hope to use AUV Sunfish to explore, create three-dimensional maps of sites, and collect samples.

The Our Submerged Past survey team at work. Dr. Kelly Monteleone reviewing sidescan sonar data as it is collected, Roby Medina driving Fishing Vessel Showtime using the kicker or small engine, and Brant Baxter watching the GPS and bottom sounder while on deck.
The Our Submerged Past survey team at work. Dr. Kelly Monteleone reviewing sidescan sonar data as it is collected, Roby Medina driving Fishing Vessel Showtime using the kicker or small engine, and Brant Baxter watching the GPS and bottom sounder while on deck. Image courtesy of Vickie Siegel, Our Submerged Past. Download largest version (jpg, 4.4 MB).
Our Submerged Past main survey team (Brant Baxter, Roby Medina, Dr. Kelly Monteleone, Vickie Siegel) in front of the survey vessel F/V Showtime.
Our Submerged Past main survey team (Brant Baxter, Roby Medina, Dr. Kelly Monteleone, Vickie Siegel) in front of the survey vessel F/V Showtime. Image courtesy of Our Submerged Past. Download largest version (jpg, 5 MB).
Vickie Siegel and Brant Baxter setting up the sidescan sonar fish for a survey during Year 1 of the Our Submerged Past expedition.
Vickie Siegel and Brant Baxter setting up the sidescan sonar fish for a survey during Year 1 of the Our Submerged Past expedition. Image courtesy of Our Submerged Past. Download largest version (jpg, 4.9 MB).
Map of survey and remotely operated vehicle dive locations for Our Submerged Past.
Map of survey and remotely operated vehicle dive locations for Our Submerged Past. Map created by Kelly Monteleone. Download largest version (jpg, 1.1 MB).

Published June 23, 2022
Relevant Expedition: Our Submerged Past: Exploring Inundated Late Pleistocene (10,600 - 17,000 years ago) Caves in Southeast Alaska with Sunfish