Design and Evaluation of a Trap for Tracking the Settling Preferences of Adolescent Crabs

Overview

The purpose of this study was to design a trap that would be used to track whether or not crabs during their megalopa stage had a settlement preference. Knowing their settlement preferences helps allow population tracking, as crabs are a keystone species and have a large role in the fishing industry in this region. This was tested at Titlow Ma rine Preserve, making this different from past research as it is open water rather than being in a contained and controlled environment. We hypothesized that the larger rocks would provide a more suitable shelter as they are more stable. We placed 3 bins, each with a different substrate, into the Marine Preserve, and collected them after a few weeks. We would then collect the species found and analyze this data. We found that the vast majority of micro-species (all belonging to the Arthropoda phylum) preferred to settle in the cobbles, followed by the large rocks, with few preferring the sand substrate. We found that the larger species tended to vary more, with the large rocks bins containing more larger species than any of the others. These results can be used for future studies as a baseline that shows the settlement preferences of Arthropods, which could be used to track populations.