Octospy: What Octopus insularis do in their dens

Octopus insularis is a benthic octopod from the tropical and subtropical Western Atlantic Ocean that inhabits semi-permanent "dens" (small crevices) in hard substrate. We used visual surveys to assess den occupancy and remote cameras at den entrances to assess activity patterns of O. insularis of South Caicos (21.5112 degrees N, 71.5190 degrees W) in the Turks and Caicos Islands (May-August, 2020 and July-December, 2021). Dens were occupied for a median of 4 days, but occupancy ranged widely (1 day-2 months), indicating migration between dens at erratic intervals. The two most prevalent behaviors were Away from the Den, time presumably spent mostly foraging, and Quiescence, when the octopus was sleeping or otherwise unreactive. Our data indicate that Octopus insularis is diurnal, with time Away from the Den peaking between mid-morning (0700-1000) and late afternoon (1600-2000), and with Quiescence peaking at night (2000-0600) and also in the middle of the day (1100-1600), although adherence to this pattern was not strict. High interindividual variation and high within-individual stability in the proportions of time Away from the Den and Quiescent suggest that individuals of this species vary greatly from each other in their hunting and resting patterns, while also showing high levels of internal consistency for at least a week. These observations will guide future research with this commercially important species, further differentiates O. insularis from congeners, and demonstrate the efficacy of minimally disruptive field techniques in studying behavior.