Localization of octopus drill holes on cowries

Octopus localize their drill holes on prey but it remains unclear how this is accomplished. Asymmetrical prey such as snails and crabs would provide cues to the octopus but the nominally symmetrical cowry presents a unique drill hole localization scenario. To investigate how octopus drill cowries we collected their shells from octopus middens in Bonaire and surveyed drilled specimens in shell collections. Cowry drill holes were predominantly localized to the ventral-posterior-lateral region of the shell, the attachment point of the columellar muscle. Cowries with multiple drill holes suggest a trial-and-error learning process leading to localization. Further studies with naive octopuses are proposed to determine the role of learning in this feeding behavior.