10 Things You Didn’t Know About Unusual Animal Sleep Habits

6. The Sleep Strategies of Migratory Fish

Migratory fish, such as salmon and eels, undertake epic journeys across vast distances, navigating complex aquatic environments to reach their spawning grounds. These migrations require immense energy and endurance, raising questions about how these fish manage to rest and recover during their travels. Research has shown that migratory fish employ a variety of sleep strategies to cope with the demands of migration. Some species, like the Atlantic salmon, engage in intermittent rest periods, where they reduce their activity levels and enter a state of low alertness. Others, such as the European eel, have been observed resting in sheltered areas, where they can conserve energy and avoid predators. The study of sleep in migratory fish provides valuable insights into the flexibility of sleep architecture and the ways in which animals adapt to changing environmental conditions. It highlights the importance of sleep in maintaining physical and cognitive performance and offers potential lessons for human endurance athletes and individuals who engage in prolonged physical activity.