Dataset: Fecal pellet elemental composition (CHN), production rates, and morphometrics from zooplankton incubation experiments collected during R/V Atlantic Explorer cruise AE2306 at the Bermuda Atlantic Time-series Study (BATS) site in Mar 2023

Zooplankton Collection

Live zooplankton were collected during the March 2023 cruise (AE2306) using a 1-m², 150-µm mesh Reeve net for fecal pellet elemental analysis experiments.

Fecal Pellet Incubation and Collection

Target zooplankton taxa were incubated individually in 1-L acid-washed plastic containers ("Copepotties") filled with 0.2-µm filtered seawater. Each container included an inner insert constructed from a 1-mm mesh-bottomed plastic cup to allow separation of fecal pellets from the zooplankton. Incubations were conducted in the dark at approximately 20°C for 8–12 hours. Following incubation, fecal pellets were collected under a dissection microscope using glass pipettes and rinsed three times with nuclease-free water. Pellets were imaged at 63× magnification under a stereomicroscope, and morphometric measurements were obtained using INFINITY ANALYZE 7 software (Teledyne Technologies, Inc).

Fecal Pellet Elemental Analysis

Individual fecal pellets were placed onto pre-combusted, pre-weighed GF/F filters (0.7-µm pore size). Filters were dried, and changes in mass were used to estimate pellet dry weight. Filters containing fecal pellets were acidified by exposure to concentrated HCl fumes for 16 hours to remove inorganic carbon and then dried prior to analysis. Carbon, hydrogen, and nitrogen content was quantified using a Costech ECS 4010 elemental combustion system. Pellet carbon density and C:N ratios were calculated using measured pellet dimensions and elemental data.