The aim of this work was to investigate whether increased sediment concentrations affect the physiological performance of juvenile specimens of the cold-water coral Caryophyllia (Caryophyllia) huinayesis by measuring growth, behaviour and respiration rates of the corals over a period of three months. The study consists of an in vitro experiment which included three different treatments: i) the control with the current natural sediment concentration of Chilean Comau Fjord, ii) a 100-fold sediment concentration of the control, and iii) a 1000-fold sediment concentration of the control. Coral recruits were taken from the aquarium facilities of the Alfred-Wegener-Institute (Bremerhaven, Germany). These were offspring of adults of C. huinayensis collected by scientific SCUBA divers in 2015 from Comau Fjord, which have successfully acclimatized and reproduced in the laboratory aquaria (see Laudien et al., 2018, 2019, 2021). Growth was measured with the buoyant weight technique and via the increase in calyx diameter using images. Behaviour, i.e. the expansion of the polyps, was visually observed four times a week. Pictures were taken of the lateral view of the corals to see if the animals retracted their tissue. Oxygen consumption was determined for 24 h in corals from the three-month experiment and in corals newly exposed to the natural and 1000-fold sediment concentration.

This dataset was generated within the framework of the co-operation between the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (programme: 'Changing Earth – Sustaining our Future', Topic 4.2), the Huinay Scientific Field Station, European Union's Horizon 2020 iAtlantic project (Grant Agreement No. 818123) and the Centre for Marine Environmental Sciences of the University of Bremen.