Platypuses are excellent swimmers and can stay submerged for varying lengths of time, depending on their activity and need for oxygen. They have the ability to hold their breath and remain underwater for extended periods. While the exact duration of time a platypus can stay underwater varies among individuals, they typically stay submerged for about 30 seconds to 2 minutes when actively foraging for food. However, they can extend this time if necessary, especially when resting or sleeping underwater. Their ability to stay submerged is aided by adaptations like webbed feet and the ability to close their nostrils and ears to keep water out.