The species diversity of deep sea corals is almost completely different between the Aleutians and Hawaii, with species transition occurring somewhere along the Emperor Seamount chain. Professor Les Watling and his team hypothesize that this boundary is determined by the flow of North Pacific Intermediate Water that comes from the Gulf of Alaska and the northwest coast of North America and crosses the Emperor Seamount chain at the Main Gap. This zonal water movement could function as a moderate to strong barrier to north-south species dispersal and may be responsible for the observed faunal differences. The team will sample seamounts on each side of the Emperor Seamount Chain Main Gap to differentiate the coral fauna and the water conditions where the corals live. During the expedition, scientists will collect high resolution video with ROV SuBastian that will help fisheries commissions and other management authorities identify vulnerable habitat. In addition to video, reliable biogeographic data will help to assess octocoral distribution, which can be used for natural resource management and policy making.

ROV SuBastian Dive 280 – Hess Rise
Date: 8/1/2019
Location: Pacific Ocean, in transit from Honolulu to Emperor Seamount Zone
Depth: about 1700m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap.

ROV SuBastian Dive 282 – Suiko Seamount
Date: 8/8/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: about 1500m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap.

ROV SuBastian Dive 283 – Yomie Seamount
Date: 8/9/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: about 1500m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.

ROV SuBastian Dive 284 – Godaigo Seamount
Date: 8/10/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: 1800m to 2200m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.

ROV SuBastian Dive 285 – Nintoku Seamount
Date: 8/11/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: 1800m to 2400m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.

ROV SuBastian Dive 286 – Nintoku Seamount
Date: 8/12/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: 1500m to 1100m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.

ROV SuBastian Dive 287 – Jingu Seamount
Date: 8/13/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: 1200m to 1500m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.

ROV SuBastian Dive 288 – Annei Seamount
Date: 8/14/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: 1700m to 2100m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.

ROV SuBastian Dive 289 – Annei Seamount
Date: 8/16/2019
Location: Pacific Ocean, Emperor Seamount Zone
Depth: 1100m to 1500m depth
Work Completed: The team was looking for deep sea corals and sponges to fill in a large biogeographic gap. They are taking deep sea coral samples and water samples.