Temperature- and size-dependent growth and movement of the North Pacific giant octopus (Enteroctopus dofleini) in the Bering Sea

Abstract

ABSTRACTOctopus growth and movement occurs during all life stages and have implications for survival, food web dynamics and reproduction. From 2009 to 2011, 1714 North Pacific giant octopus (Enteroctopus dofleini) were tagged and recaptured in the eastern Bering Sea with visible implant elastomers to better understand the ecology of this data-poor species. Over this period, 246 of the tagged individuals were recaptured. In autumn, when temperatures were warmest, E. dofleini had higher growth rates and moved more than in the colder winter months. For both short- and long-term recaptures, small octopus grew faster than large octopus. Movement of octopus over short- and long-term periods was low for very small and very large octopus and high for median-sized octopus, which is likely to be a function of maturity status and reproductive activities. Approximately 80% of recaptures moved less than 2 km from the initial tagging location for time periods up to a year, suggesting long-term site fidelity. As temperature and size may be tightly linked to growth and movement rates for E. dofleini in the eastern Bering Sea, predicted climate warming will likely alter ecological processes for the species and impact their distribution.