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Your Complete Guide to What Whales Eat

a body of water

Whales are among the largest animals on Earth. In fact, the blue whale is the largest animal that has ever lived. Obviously, an animal that large needs a lot of food to keep it going, but what do whales eat?

Whales are carnivores that live by eating the meat of other, smaller creatures. There are two main types of whales: toothed whales and baleen whales. The type of whale is the main factor that determines what kind of food it eats, but there are also other factors such as where the whale lives.

Toothed Whales

Toothed whales are more or less what they sound like: whales that have teeth in their jaws, the same as humans do. However, toothed whales do not use their teeth as humans do. They use their teeth for catching and holding food before swallowing it whole. If the food is too large to swallow whole, they can hold it in their teeth and shake it around until it breaks down into smaller pieces.

Though not as large as some of their counterparts, dolphins are considered whales. All dolphins have teeth, meaning that they are examples of toothed whales. The killer whale is also considered a dolphin, though one of an exceptionally large variety.

What Do Toothed Whales Eat?

Toothed whales hunt for food in the ocean. Therefore, for the most part, they eat fish of all different types. Because they typically swallow the food whole, the size of the whale influences the type of fish that it can eat.

Toothed whales also commonly eat squid, which is not a fish but a cephalopod. Sperm whales, in particular, are known for eating squid. They are the primary predator of the giant squid. Different types of squid come in multiple sizes, and smaller whales may eat smaller types of squid.

Where a toothed whale lives also influences what it eats. For example, killer whales, also known as orcas, are the largest dolphin species and are considered apex predators, meaning that no other animals hunt and feed on them. Like other dolphins and toothed whales, orcas feed on fish. However, because they prefer to make their homes along coastal areas, they also hunt and feed upon sea birds and seals.

How Can You Tell What a Toothed Whale Eats?

You can get a clue as to the diet of an individual whale by looking at the condition of its teeth. If the teeth look worn down, the whale probably feeds primarily on small fish, using the teeth to catch and hold its prey and breaking it down by vigorous shaking. However, if the teeth are not worn down, the whale probably feeds on large mammals, such as seals, that it is able to catch and swallow whole.

How Do Toothed Whales Find Food?

Some toothed whales live their lives in very deep water, where little light penetrates. At these depths, hunting for food by sight would be challenging at best. Therefore, whales use echolocation to find their food. They send out a series of high-pitched noises. If there are any other animals or objects in the vicinity, the sound waves bounce off them and echo back to the whale. The whale perceives the reflected sound, which gives it information about what is in its path and whether it is edible.

a close up of a fish

Baleen Whales

A baleen is a plate that hangs down from the top jaw of a whale’s mouth. Unlike teeth, a baleen is not made of bone. Rather, it is made of keratin, the same tough material found in human fingernails. The baleen is divided into thin fibers that resemble the teeth of a comb or the bristles of a brush. Baleen whales feed on very small organisms that get caught in the baleen. Examples include krill, which is a very small type of fish, and marine plankton. It is ironic that some of the largest animals in the world, such as blue whales and humpback whales, feed on some of the smallest. If small fish species, such as anchovies, get stuck in the whale’s baleen, it can swallow them as well along with its regular food.

How Does Baleen Feeding Work?

When a baleen whale locates a school of krill, it builds up its speed and swims right towards it. As it swims, it opens its mouth wide, and its speed help to draw the krill and the water in which they are swimming into the mouth of the whale.

The whale has expandable grooves in its throat that allows it to increase the size of its mouth so it can hold more water and krill. The act of opening the mouth causes the whale to slow down because of the drag it creates.

The whale closes its mouth once it is full of water in which krill are floating. Contracting the throat grooves pushes the water out the sides of the mouth through the baleen. The krill are too large to fit through the baleen and become stuck there, allowing the whale to swallow them.

Do Baleen Whales Use Echolocation?

The structure of a baleen whale’s head prevents it from using echolocation to find food the way that toothed whales do. Baleen whales are able to make sounds, but they are used primarily for communication with one another rather than locating food.

What Other Techniques Do Baleen Whales Use To Find Food?

While baleen whales tend to be solitary foragers, some hunt for food in groups. For example, humpback whales use a technique called a bubble net to catch krill or small fish. They swim in circles around the prey to gather them into a ball. One of the whales uses its blowhole to blow bubbles in a circular motion. As the bubbles rise, they give the appearance of trapping the prey within the column. Another whale produces a 180-decibel sound from the bottom of the net. The prey swim upwards to get away from the noise, and the whales swim up quickly to catch them.

Whales are fascinating creatures, and one of the best ways to learn more about them is to see them in their natural habitat.