Behavioral responses to weak electric fields and a lanthanide metal in two shark species

► A standardized test of metal shark deterrents for bycatch reduction is provided. ► Sensitivity to electric fields is similar for Squalus acanthias and Mustelus canis. ► S. acanthias avoided neodymium, M. canis avoided it (alone) or preferred it (group). ► Observed differences may be due to feeding motivation and competitive interactions. ► Results demonstrate variable response to lanthanide metal across and within species.