Using taxonomically-relevant condition proxies when estimating the conservation impact of wildlife tourism effects

Meyer et al (2019) recently proposed that the nutritional condition of white sharks is unaffected by cage diving tourism. This conclusion was reached after analysing changes in the fatty acid profile of muscle samples collected from sharks that had spent more time around cage diving and contrasting them to sharks relatively unexposed to these activities. Here we want to caution on the interpretation of these results which do not fully take into consideration the way energy metabolism functions in elasmobranchs. We provide some alternative metabolic targets which could be retrieved from the field and would be more relevant to estimate the potential population consequences of tourism disturbances on white sharks.