Distinct Patterns in Historical Mobility and Catch Flexibility Underscore Intra-Port Variation in Potential Adaptive Capacity to Climate Change.

Selden, Rebecca¹, Zoe Kitchel², Kaycee Coleman², Borja Nogue³, Leo Calzado², Kevin St. Martin², ¹Wellesley College, ²Rutgers University, ³Nogue, Borja Institut de Ciència i Tecnologia Ambientals Universitat Autònoma de Barcelona

As oceans warm, marine species are shifting their distributions to stay within preferred temperatures. For coastal fishing communities, these shifts in availability can result in loss of important historical species or gains of species not traditionally harvested. In our past research with trawl fishing communities, we observed that fishing communities have responded to past change by altering where they fish or what they catch. To understand the relative vulnerability and adaptive capacity of fishing communities throughout the Northeast, we extended our analysis to the entire coast across gear types. We used the degree of mobility in fishing grounds and the extent of flexibility in their catch composition as a metric of potential future adaptive capacity. We find that gear types had predictable differences in interannual variability in catch composition or fishing grounds. Gear types that were more selective for a small number of species had lower flexibility in catch composition than less selective gear types like bottom trawl. Lobster and small trawl fishing communities were dominated by those that utilized a consistent fishing ground, while many large trawl and dredge communities varied widely in the areas harvested. However, ports within a gear type could demonstrate substantial variation around these averages, suggesting distinct constraints or opportunities for adaptation that vary by port. Likewise, within a port, different gear groups varied substantially in their mobility and catch flexibility. This highlights the potential power for considering distinct fleets within a port that can complement port-level social vulnerability metrics.