The causes of free-living chelonian mortality events are often unknown because of infrequent recovery of remains and rapid postmortem decomposition. This study describes a technique to harvest bone marrow and detect frog virus 3-like ranavirus (FV3) using quantitative polymerase chain reaction in skeletonized eastern box turtles (Terrapene carolina carolina) (N = 87), and assesses agreement with concurrent perimortem samples (N = 14). FV3 was detected in bone marrow samples from 12 turtle shells (14%). Three of 14 turtles had detectable FV3 loads in both bone marrow and perimortem samples, two turtles had detectable FV3 in bone marrow only, and nine turtles tested FV3 negative in both bone marrow and concurrent perimortem samples. There was substantial agreement between FV3 testing of bone marrow and other tissues (κ = 0.658). Harvesting bone marrow from shells is easily performed and can serve as a means for biologists and wildlife veterinarians to improve postmortem surveillance for systemically distributed pathogens, including FV3.