RIASSUNTO
All commercial fishery species harvested globally either live on or near the seabed (also referred to as the benthos or benthic environment) or employ life history strategies or behaviors linked to benthic processes. The act of pursuing and catching benthic and demersal species requires operating fishing gear on or very near the seabed, resulting in direct gear-seabed contact. It is essential to further quantify bottom contact, given that contact made by commercial fishing gear with the benthos is considered one of the most significant human impacts on the oceanic environment. There are several devices that measure bottom contact; these devices, however, usually address only one point of contact, such as the center of the footrope, when other components of the fishing gear may be making contact as well. An NPRB-funded study by Rose et al. (2016) used multiple bottom contact sensors (accelerometers) hung from the footrope of a trawl net to quantify bottom contact; however, this study was not conducted under real fishing conditions (the codend was open). Rose et al. provided statistical analyses of the gear configurations as they relate to habitat susceptibility, but examination in terms of components, material, and clearance was beyond the scope of the work. Here I propose an algorithm to examine these covariates as estimators of habitat susceptibility by reassessing the imagery/data from the field, constructing quantitative models based on these covariates, re-running the applicable models, and examining the spatial distribution of seabed clearance for each material and component combination. These data, along with an assessment of the current state of science and technology in bottom contact sensors, will aid in determining the best methods for measuring bottom contact and/orseabed clearance in future field-based portions of this study.