Lumpfish, Cyclopterus lumpus, distribution in the Gulf of Maine, USA: observations from fisheries independent and dependent catch data

The Gulf of Maine (GoM) is one of the fastest-warming parts of the world’s oceans. Some species’ distributional shifts have already been documented, especially for commercially-important species. Less is known about species that are not currently exploited but may become so in the future. As a case study into these issues, we focus on lumpfish (Cyclopterus lumpus) because of the recognized and timely need to understand wild lumpfish population dynamics to support sustainable fisheries and aquaculture developments. Using occurrence data from five different fisheries-dependent and -independent surveys, we examined lumpfish distribution over time in the GoM. We found that lumpfish presence was more likely in spring and correlated with deeper waters but not bottom temperature. Since 1980, lumpfish presence has increased over time, moved farther offshore, and shifted northward. Our work provides preliminary information for resource managers to ensure that lumpfish are harvested sustainably for use in emergent lumpfish aquaculture facilities. An understanding of lumpfish occurrence patterns may enable lumpfish aquaculturists to utilize the most local populations, thus maintaining the local genetic integrity of fish slated for release into net pen salmonid farms.