Happy families? Insight into the coexistence between the curled octopus (Eledone cirrhosa) and common octopus (Octopus vulgaris) in waters around the UK

Abstract This case study investigated the co‐occurrence of the curled octopus (Eledone cirrhosa) and common octopus (Octopus vulgaris), in waters around the United Kingdom. The findings suggest that coexistence may be maintained because of the lack of competition for E. cirrhosa against the seemingly declining O. vulgaris populations, and that habitat and temporal partitioning are the likely mechanisms. It is contemplated whether species misidentification may an important factor in masking the accuracy of population dynamics of co‐occurring octopus species, and, as such, potential uncertainty in octopus coexistence and any future fishery management decisions. It is confidently suggested that, currently, only two octopus species are resident to UK waters. Now, further studies should include diet partitioning to determine whether diet partitioning is a mechanism for E. cirrhosa and O. vulgaris coexistence, and monitoring may make us understand their population dynamics.