Detailed methodology for MOCNESS tows can be found in Wishner et al. (2018). Briefly,  a 1 m² MOCNESS fitted with 222 micron nets was used to collect vertically stratified environmental data and plankton samples (9 nets per tow, 0-1000 m, 25-100 m intervals).  Some tows also targeted oxygen minimum zone features. Nets were rinsed with filtered seawater and whole samples were preserved in 4% sodium-borate buffered formaldehyde. 

Detailed methodology for sample preparation and analysis can be found in Davis et al. (2023). Foraminifera with intact cytoplasm were isolated from tow material to ensure samples were living at the time of collection. Shells of G. hexagonus were subjected to oxidative cleaning: shells were bathed individually in a 1:1 mixture of NaOH and H₂O₂ for 10 minutes, then rinsed in deionized water. Shells were then mounted on carbon conductive tape on a glass slide. Trace element analysis was completed at the College of Earth, Ocean, and Atmospheric Sciences at Oregon State University using a laser ablation system (Photon Machines 193 nm ArF laser with an ANU HelEx dual-volume laser ablation cell, 65 mm spot size, a 4 Hz rep rate, and a fluence of 0.85 J cm^-2) coupled to an iCAP quadrupole ICP-MS. Standards NIST 610 and NIST 612 were ablated every 10 samples.