Video observations of a bathypelagic cirrate octopod Cirroteuthis muelleri

These data are video observations of a bathypelagic cirrate octopod C. muelleri performed by remote operating vehicles (ROVs) and PELAGIOS towed camera system. Supplementary videos 1, 2 and 8 were recorded by ROV 'Aurora Borealis' during the cruise on R/V 'Kronprins Haakon' in the Fram Strait in October 2021. Supplementary videos 15–18 were recorded by PELAGIOS during the cruise PS126 on R/V 'Polarstern' in the Fram Strait in May and June 2021. Supplementary video 3 was recorded by ROV 'PHOCA' during the cruise PS121 on R/V 'Polarstern' in the Fram Strait in August 2019. Supplementary videos 9–14 were recorded by PELAGIOS during the cruise PS121 on R/V 'Polarstern' in the Fram Strait in August and September 2019. Supplementary videos 4–7 were recorded by ROV 'KIEL6000' during the SO276 cruise on R/V 'Sonne' off the Iceland–Faroe Ridge in July 2020. Supplementary videos 19–22 were recorded by ROV 'KIEL6000' during the SO276 cruise on R/V 'Sonne' off the Iceland–Faroe Ridge in June and July 2020. Majority of the videos (Supplementary videos 9–22) were recorded during the routine transects. Supplementary videos 1–8 are recorded when cirrate octopods were accidentally encountered on the seafloor.