Analysis of Potential Interaction Whale-Lobster Gear Interaction

Using interviews and imagery to map the timing and location of lobster fishing on the Maine Coast

As part of a two-year effort to identify potential interaction between lobster fishing gear and endangered whales along the coast of Maine, we are mapping fishing effort. The goal of stage 1 if the project is to create a spatially and temporally accurate representation of lobster fishing activity along the Maine coast. Previous research by the author has demonstrated that frequently used lobster fishing areas are generally associated with discontinuities in the seafloor, such as shallow undersea ridges and deep canyons. Fishing patterns can vary among communities based on other variables such as tides, substrate types and local variations in the arrangement of coastal features.

In order to capture as much variation in lobster fishing patterns as possible, individuals from dozens of Maine fishing communities were invited to participate in a series of small group interviews. During these sessions, fishers are asked to demarcate their seasonal fishing grounds on hard-copy NOAA nautical charts.

Lobster gear are arranged in various combinations of vertical and ground line. Singles result in more vertical line in the water, while trawls of 4+ traps result in more ground line. Both types of line may interfere with whales in different ways, so combinations of gear types can be modeled to see which has the greatest potential for avoiding entanglements of endangered whales.

Using a dasymetric mapping technique, seafloor imagery-derived products including bathymetry and surficial geology, will be used to extrapolate the fishing data to finer levels of spatial aggregation.

The outcome of this work will be the most complete representation to date of where and when lobster fishing takes place, and will become a critical input to a model of potential whale-lobster gear interactions.