Interaction with enrichment objects depends on color and increases after feeding in some elasmobranchs but not others (2025)

Smith, A. B., Landesman, J., Williamson, L. et al.

Abstract

Environmental enrichment is important for the long-term wellbeing of captive organisms and is an understudied topic in aquatic taxa, particularly ectothermic organisms such as elasmobranchs. This study examines how individual elasmobranchs use environmental enrichment objects before and after feeding. The species included were Heterodontus francisci (horn shark), Cephaloscyllium ventriosum (swell shark), Triakis semifasciata (leopard sharks) and Caliraja inornata (California skate). Results indicate that interaction peaks post-feeding with animals interacting with objects that have a different color relative to the surrounding environment. Interaction frequency is highest after feeding following an initial lag phase, particularly for T. semifasciata. These data suggest that environmental enrichment should take into account the optical range of elasmobranchs as well as timing of when enrichment objects are introduced to increase enrichment efficacy.