Benthic habitat influences sea scallop distributions and swimming behavior based on underwater imagery and machine learning

Understanding the drivers of Atlantic sea scallop distribution and abundance is a priority for fisheries management. While factors influencing scallop habitat selection and recruitment remain poorly understood, the increasing use of optical surveys for scallop assessment has opened new opportunities for studying juvenile and adult scallop distributions. Yet manual image annotation is time-consuming, limiting the potential of these datasets. Automating this process could improve biomass estimates and advance research on scallop ecology by enabling the analysis of larger datasets in a fraction of the time required for manual annotation. This study aimed to (1) use automated scallop detectors and benthic habitat classifiers to generate accurate scallop plus habitat datasets for large numbers of images from Habitat Mapping Camera surveys of scallop grounds and (2) use these datasets to develop models to assess how benthic habitat influences sea scallop distributions and age-specific swimming behavior. Scallop detectors and habitat classifiers were developed for the computer vision platform Video and Image Analytics for Marine Environments. Density models using automated datasets indicated that benthic habitat components (gravel, shell hash, bryozoans, sea star beds, sand dollar beds, and sand waves) influenced scallop densities, with some trends for habitat preference shifting with age. Swimming models confirmed that juvenile scallops swim more frequently than adults, particularly in areas with lower bryozoan densities. This work highlights the value of using automated tools to process large-scale optical datasets and provides new insights into habitat-specific scallop behavior across life stages. • Sea scallop and benthic habitat classifiers were developed using machine learning. • Scallop distributions and swimming behavior were modeled using automated datasets. • Benthic habitat influences scallop densities and impacts change as scallops mature. • Benthic habitat impacts on scallop swimming behavior change as scallops age. • Automated detectors can be successfully used to analyze large optical datasets.