Updated project metadata. One of the greatest cyclical patterns in the pelagic ecosystem is the daily vertical migration of various zooplankton and fish to depth, a process referred to as diel vertical migration (DVM). DVM is considered to be energetically costly as tiny plankton migrate hundreds of meters in a 24 hour period. To study the metabolic demands of DVM, the copepod Pleuromamma xiphias was collected during upwards and downwards migration off of Bermuda. Data-dependent acquisition on the Q-Exactive detected >1600 proteins, 180 of which were differentially abundant between the two sampling periods.