Dataset: NanoSIMS measurements of skeletal organic matrix and aragonite extension in lab-grown scleractinian cold-water corals from February of 2022 to July 2023

Cameca NanoSIMS 50L at the Environmental Molecular Sciences Laboratory at the Pacific Northwest National Lab (PNNL). In addition to NanoSIMS analyses of our experimental and control samples, we also analyzed regions of samples that were only naturally grown. Using both O^-  (RF-plasma) and Cs⁺ source beams, we reconstructed 35 x 35 μm² maps of elemental and isotope ratios. Specifically, negative ions collected included ¹²C¹⁴N^-, ¹²C¹⁵N^-, ¹²C^-, ¹²C₂^-, and ³²S^-. Positive ions included ⁶Li⁺, ²³Na⁺, ²⁴Mg⁺, ³⁹K⁺, ⁴⁴Ca⁺, ⁵⁵Mn⁺, and ⁸⁸Sr⁺. The primary beam current was 3pA for Cs⁺ and 10 pA for O^- with a 3 ms dwell time per pixel. In order to standardize the N isotope composition of measured corals, natural abundance yeast standards were measured at the beginning of each day of Cs⁺ analyses. No presputtering was used, but data were collected in a series of 6-8 planes, such that it was possible to remove frames associated with gold coating or with signs of surface contamination (usually indicated by high Na signals or low ¹²C signals). Each NanoSIMS image stack consisted of 3-8 planes, depending on the number removed due to surface contamination, which were drift-corrected and summed to generate a single image for each secondary ion species detected. 

Live B. elegans adults for this study were collected near Friday Harbor Labs, San Juan Island, Washington, USA in December 2020 at a depth of ~10 m by divers. Individuals were secured using flexible PVC tubes in seawater-filled plastic containers and shipped overnight with ice packs to Minnesota for coral culturing. Upon arrival at St. Olaf College, corals were kept in artificial seawater-filled bottles and planulae appeared in bottles almost immediately. After larvae settled and metamorphosed, both juvenile corals and adults were allowed to recover for ~6 months in plastic, artificial seawater-filled bottles and fed Artemia salina nauplii 2x weekly.