How do salt-water mammals stay hydrated?

Although some marine mammals are known to drink seawater at least on occasion, it is not well established that they routinely do so. They have ... A marine mammal can minimize its salt and water balance problems by following the same advice my doctor gave me to keep my blood pressure down: avoid salty food. read more

These marine mammals must remove the excess salt consumed due to such salty prey. Invertebrates do, however, possess a high water content that can be provided to the mammal following digestion. marine mammals have the ability to produce water from the metabolic breakdown of food. read more

The Answer: Most sea mammals get their water from the food they eat. Their bodies are designed to absorb water using the metabolic breakdown of carbohydrates and fat from digestion. read more

In contrast, marine mammals that feed on fish consume food with a salt content similar to that of their own blood, thereby avoiding the problem entirely. Indeed, a study of California sea lions showed that, on a diet of fish, these animals can live without drinking fresh water at all. read more