Fishermen's Knowledge: A Valuable Resource for Improving Our Understanding of the Habitat Preferences of Atlantic Halibut Off the Coast of Maine

The Atlantic halibut (Hippoglossus hippoglossus) is considered a data-poor species in the Gulf of Maine. Biannual fisheries-independent trawl surveys catch very few halibut each year and very rarely capture adults, which can outswim trawl nets. The Maine Department of Marine Resources carried out a cooperative research survey from 2000-2004 and 2007-2008 using longline gear that is better suited for catching halibut. We re-examined this and other data to evaluate the habitat preferences of halibut off the coast of Maine. The habitat preferences of Atlantic halibut in the Gulf of Maine are not well understood. When looking for key environmental drivers of halibut distribution off the coast of Maine, we found some limitations to the usefulness of currently existing datasets and so we collected additional information from a largely-untapped source: Maine’s commercial halibut fishermen. Fishermen provided valuable information on the biology, behavior, and distribution of halibut that could not be addressed in our statistical analysis. By examining both quantitative datasets and fishermen’s knowledge we brought to light new information on halibut behavior and their distribution off the coast of Maine, including flexible sediment type preferences, a varied diet, size-segregation, and evidence of year-round coastal residency.