Impacts of acute hypoxia on the short-snouted seahorse metabolism and behaviour

Abstract

AbstractSeahorses are one of the most unique and enigmatic animals, recognized as flagship species for several conservation issues. Unfortunately, seahorses’ populations have been declining worldwide and their unique lifestyle may constrain the ability of these animals to evolve in the future climate scenarios. They inhabit shallow coastal waters that display daily or seasonal environmental fluctuations, Yet, few studies have scrutinized the impacts of climate changes on these iconic species. Within this context, the objective of this work was to test the effects of an extreme hypoxia exposure (~ 27% dissolved oxygen) on the metabolism, behaviour and food intake of the temperate seahorseHippocampus hippocampus. Regarding metabolism, hypoxia exposure led to a significant reduction in metabolic and ventilation rates. Seahorses showed signs of movement lethargy under oxygen depletion. The results show that hypoxia induces metabolic and behavioural changes that may jeopardize the development and survival of these iconic organisms.