Dolphin Feeding Habits

In a few cases, however, underwater photographers have been lucky enough to catch wild dolphins feeding and occasionally, a dolphin will catch a fish on the surface. Scientifically, much of the information about what dolphins need to survive and their physiology comes from dolphins in captivity or research institutes. Most scientists however, do not feel that the habits of captive dolphins can be compared to those in captivity.

We do know that dolphins feed mainly on fish. They are not really hunters but rather seem to be happy with the most abundant species that is available to them. Consequently, the diets of dolphins in the wild tend depend on the area in which they're living as well as the time of the year. Dolphins swallow their food whole, without chewing. They using the muscles at the back of their tongue and throat to squeeze the salt water out and the fish down. Dolphins tend to try and take their fish head first which researchers believe keeps the fins and spines folded back. That way the dolphin does not injure its throat. While adult dolphins can eat fish that weigh up to 5 kilograms, smaller, younger dolphins tend to stay with smaller fish.

When foraging for food, dolphins emit sound waves (echolocation) which reflect off the fish. The returning echo acts as radar, letting the dolphin know exactly where the fish are. Some researchers also believe that dolphins emit loud noises to stun the fish, making them easier to catch.

Dolphins usually hunt in groups, forming a circle or a U shape and herding the fish, they then simply swoop through the school picking off as many as they like. Dolphins have also been known to take fish right out of the nets of fishermen. It has also been reported that dolphins have even used humans to provide their food supplies. In Africa, bottlenose dolphins actually herd mullet to the shallow water where fishermen wait with nets to trap the fish. The cooperative effort apparently involves the fishermen allowing the dolphins to take their fill and they then take the rest.

Dolphins travel to find food. If they remained in only one small area, they woulf quickly exhaust the available food supply; therefore, they tend to leave and then revisit various feeding grounds periodically.

How much a dolphin actually need to eat really depends on what he's actually eating. Certain types of fish for example, have higher fat content than others and consequently provide more energy at a lesser quantity than the fish that have a low fat content. Most research suggests that a dolphin needs to eat approximately 1/3 of their body weight in fish on a daily basis.