Diet and Feeding Habits
The walrus is a large animal, and their feeding efforts always take place in the water. They live in shallow regions of the water where they can easily gain access to bottom dwelling organisms in the water. They rarely will dive more than 262 feet to find food. It is important for them to be able to find lots of food. Many hours each day are spent foraging for food. That amount of time though varies based on their findings and even the time of year.
They are opportunistic so they will take advantage of the various types of food that they can find. They do seem to have a preference for certain foods though when they are available. Clams are one of the sources of food that they seem to enjoy the most. When they do find them, they will dine on them heavily.
What a walrus will feed on depends on various factors. This includes their location and the time of year. They have been known to consume mollusks, sea cucumbers, tunicates, soft corals, tube worms, shrimp, and crabs. At times, they will also consume carcasses of other types of pinnipeds that are smaller than they are. They don’t have very good vision, but they do rely on vibrissae to help them identify food in the water.
The water is very murky but they seem to do well with their other senses to successfully find their food sources. Studies show that the walrus has fewer taste buds than other pinnipeds. However, those taste buds also are larger than what is found on other pinnipeds. It is still unknown what their overall sense of taste happens to be. However, since they do have food preferences it may indicate that it is significant.
They don’t chew their food, but the check teeth do show signs of wear as the walrus gets older. It is believed to be the result of sand particles that enter the mouth as they are feeding. It isn’t uncommon for small pebbles and stones to be found in the stomach contents of deceased walrus. However, experts don’t feel that this causes them any harm. It is simply a correlation that occurs with their feeding habits.
Suction is a big part of the feeding process for the walrus. For example, when consuming clams they will use their suction to remove the meaty part of it to consume. The process of clearing the murky waters with the flippers to be able to find food helps the entire ecosystem where the walrus lives. This foraging process allows for nutrients to be released into the water and it also aids in the overall movement of many small organisms that live at the bottom of the water. It is a myth that they use their tusks to dig for food in the sandy bottom of the water.
The walrus has been documented consuming the carcasses of young seals when their normal sources of food are hard to find. There are also some isolated accounts of walrus that only seem to consume seals. These are typically going to be very large male walrus. They are easy to identify as their bodies are stained with grease from the blubber of the seals they consume.
Consuming large amounts of food is important to the survival of the walrus. Each day, they will consume anywhere from 3% to 6% of their total body weight. They can consume thousands of clams in a single feeding session. Twice per day, they will fill their stomachs to capacity if the food resources are available.
They need to build up layers of fat known as blubber. This help them to stay warm both in the water and on land. It also helps them to conserve energy as they move in the water. They tend to eat more as winter approaches. They will spend a great deal of their time in the summer months eating. This helps them to get ready for the migration in the fall that takes them to the South. They will feed heavily during that migration too.
They will eat far less when they are migrating in the spring, which takes them back to the North. During breeding season, the males will reduce their feeding by up to half. Females that are pregnant may increase their feeding consumption by up to 40%. They seem to eat more and more as the birth gets closer.
The young offspring will consume milk from their mother’s body for about the first year of life. However, during that span of time they will also be introduced to various forms of food and the process of hunting for it. They will consume some types of organisms along with the milk they continue to get from their mother. Around one year of age, they will be fully weaned.