Subtidal Habitat Mapping in Cook Inlet

Scope of Work:

The objectives of this study are to 1) develop benthic habitat maps in areas of sea otter use and areas currently lacking sea otters, 2) quantify biological and physical habitat attributes across a gradient of sea otter density to understand the correlation of sea otter density to benthic habitat, and 3) develop predictive maps for areas within study sites of likely sea otter utilization due to expansion within the Cook Inlet lease sale area.

Data collection will utilize Remotely Operated Vehicle (ROV) surveys. ROV surveys, equipped with single-beam sonar, will be conducted in areas of high and low sea otter density determined using previously collected data by USGS, USFWS, and NPS. Surveys will be conducted in Lake Clark National Park and Preserve, Katmai National Park and Preserve, Kamishak Bay, Kenai Fjords National Park, and Kachemak Bay. ROV imagery/video will be visually processed for substrate, vegetative cover, and invertebrate composition. Single beam sonar will be processed to produce bathymetric structural complexity models. Spatial statistics will be run on overlaid maps of sea otter locations and habitat components to correlate sea otter habitat with subtidal habitat type. The resulting correlations will be applied to ROV-mapped habitats in Cook Inlet that are not currently occupied by sea otters in order to predict potential locations of sea otter expansion.