Depending on a whale’s size, environment, and species, their diets can vary from small aquatic life forms such as fish, shrimp, larvae, plankton, crabs, krill, and large squid to marine mammals such as sea lions, walruses, seals, seabirds and even large whales.
To help whales hunt for food, some species hunt together in collaborative groups using sophisticated team-oriented hunting methods to stalk, isolate and capture their prey. Others rely on their large size and filter-feeding method to capture most of their food.
Toothed whales often use a method known as echolocation to help them locate food sources that may be difficult to find in dark light fewer environments. Below you will learn about the hunting methods of various whales within the baleen whale and toothed whale suborders.
Baleen whales
Baleen whales hunt for food using a technique known as filter feeding in which they swim towards their prey with their mouths open and filter food through their baleen bristles, which look similar to the bristles found on a comb. The baleen bristles act as filters by trapping prey such as fish, shrimp, and krill in the baleen bristles while allowing enough space for debris and water to pass through.
Gray whales are unique because they are one of the only species of whales that consistently eat from the bottom of the ocean. To capture food, gray whales swim to the bottom of the ocean and roll on their side, causing the water and sand to lift various sea sediments as well as their prey, and they will eat everything that comes up from crabs and larvae to plankton and small fish.
Humpback whales use a hunting technique known as bubble netting or lunge netting. Bubble (lunge) netting takes a group effort, and each whale plays a specific role in capturing fish.
Some whales will swim around the fish and blow bubbles, which causes the fish to form into a tight group, while others make loud noises scaring the fish and causing them to move towards the surface of the water. Once the fish move to the surface, they lunge towards the fish with their mouths open and try to eat as many as they possibly can.
Toothed whales
Toothed whales are active hunters and can sometimes eat larger prey than baleen whales. Killer whales (this species belongs to the dolphin family), for example, hunt in well-organized groups. These dolphins eat various foods such as fish, squid, sea lions, walruses, seals, sharks, and even large whales. They are also extremely social, and relationships between killer whales can last a lifetime.
The sperm whale (the largest of the toothed whales) typically prefers a diet containing octopus, large squid, and some fish. These whales can dive over 3,000 feet underwater and can remain submerged for over an hour when hunting for prey. When observed up close, circular marks can be found on and around the whale’s head from confrontations with octopus and large squid latching onto its head in an attempt to keep from being eaten.
Compared to the social structure of killer whales, sperm whales live solitary lives, often leaving their pods to travel alone or move to other small pods. Unfortunately, not much information is known about how sperm whales hunt for squid due to the whale’s deep-diving excursions, making it difficult for scientists and marine biologists to study their hunting methods effectively.
Diets of various whale species
- Beluga whale – Beluga whales live on a diet of fish, crustaceans (such as krill), squid, octopus, crabs, sandworms, and other small prey.
- Blue whale – Blue whales primarily eat krill, although other small ocean creatures such as copepods can be ingested as well.
- Bowhead whale – The typical diet of a bowhead whale contains small prey such as plankton, krill, copepods, and mysids (tiny crustaceans).
- Gray whale – Gray whales primarily eat krill, small baitfish larvae, shrimp, and herring.
- Humpback whale – Humpback whales are known for eating various small fish, krill, salmon, herring, mackerel, and capelin.
- Killer whale – Killer whales feast on small aquatic life forms such as fish and squid and larger mammals like sea lions, seals, and whales.
- Minke whale – Minke whales are known for eating small fish, krill, copepods, cod, herring, capelin, and pollock, among other small sea creatures.
- Narwhal whale – Narwhals can be found hunting flatfish, cod, shrimp, Gonatus squid, and other forms of benthic prey.
- Southern whale – The primary diet of southern right whales consists of copepods, krill, mysids, and plankton, among other tiny crustaceans.
- Sperm whale – A standard diet for sperm whales consists of medium to large squid and octopus with occasional fish consumption.