Swallowing sea water by marine mammals like the Atlantic Bottlenose Dolphin
would be harmful. Yet, water is required for survival. How is this possible in a salt water environment in the ocean or in
captivity? The dolphin obtains its fresh water from its food. Fish, squid, and crustaceans such as shrimp are composed of
approximately 70% fresh water. The dolphin's hydration (fresh water intake) is obtained entirely through its food. In captivity,
dolphins are typically fed previously frozen fish and squid. Compared to fresh foods, these frozen foods when thawed lose
a portion of their water content and additional fresh water is required by the captive dolphin to maintain proper hydration.
This is done by gently placing a lubricated gastric (stomach) tube down the dolphin's throat and into the stomach. Fresh water
is then funneled into the animal by way of this tube. The elasticity of the dolphin's esophagus makes this process
more easily tolerated by the animal. Also, because the throat leads only to the stomach and not to the lungs, there is
no chance of aspirating water into the animal's respiratory system. Hydration of captive dolphins is done after at least a
5 hour fast in order to prevent regurgitation of any undigested stomach contents. As the dolphin does not have a gag
reflex, this is easily performed. This procedure also acts to desensitize the animal to use of the gastric tube, should it
be needed at some point in the future to supply other liquids to the animal (such as medications).
Another way in which the dolphin may be hydrated is simply by injecting
its fish with small volumes of fresh water prior to feeding those fish to the dolphin.
Understanddolphins.com contains information condensed from a number of reputable technical sources,
peer reviewed journal articles, and respected dolphin research facilities, as well as from my personal experiences and
observations as a dolphin VIP Tour Guide and Educator.
I have made every attempt to support the information presented in this site with video and still
photographic images. On a regular basis I plan to produce more of these images and will continue to update the site with these
as well as with any new and scientifically verified information which becomes available.