Identifying VMEs on Cobb Seamount using visual data

We identify vulnerable marine ecosystems (VMEs) on Cobb Seamount by applying a quantitative approach to assessing the Food and Agriculture Organization (FAO) criterion of structural complexity for identifying VMEs (FAO 2009) developed by Rowden et al. (2020). VMEs are identified using visual data as outlined in the North Pacific Fisheries Commission’s (NPFC’s) framework for identifying data to identify VMEs (See Annex 2.3 in NPFC 2023a and NPFC 2023b). Using Rowden et al.’s (2020) approach, we calculated a VME density threshold of 0.6 VME indicator taxa colonies m^-2. Applying our threshold to visual data from autonomous underwater vehicle (AUV) transects on Cobb Seamount, we identify five areas as VMEs ranging in size from 50 – 200 m². Using the NPFC’s move-on distance of 1 nautical mile following a VME encounter (NPFC 2023a; NPFC 2023b), we propose a fisheries closure area of 1 nautical mile around the identified VMEs to protect them from potential significant adverse impacts (SAIs). We propose two areas as VME protection sites on Cobb Seamount: one in the northwest corner and one in the northeast corner with areas of 24.7 km² and 13.7 km², respectively.