This article discusses the development of a biocompatible hydrogel combining keratin protein and liquid metal (EGaIn) to create wearable electronics for monitoring the health of marine animals. The hydrogel, named KELM, exhibits excellent biocompatibility, high mechanical flexibility, and impressive conductivity, making it ideal for sensing applications. The authors demonstrate its successful application in monitoring the heartbeats of various aquatic organisms, highlighting its potential for marine health monitoring and other wearable electronic applications.