13 C tracer experiments were conducted at sites spanning the steep oxygen, organic matter, and biological community gradients across the Arabian Sea oxygen minimum zone, in order to quantify the role that benthic fauna play in the short‐term processing of organic matter (OM) and to determine how this varies among different environments. Metazoan macrofauna and macrofauna‐sized foraminiferans took up as much as 56 ± 13 mg of ad...