The bowhead whale is one of the planet’s largest and longest-living mammals, inhabiting the cold Arctic and sub-Arctic waters. Its defining features are its immense size and a thick layer of blubber, up to 1.6 feet deep, which provides insulation and protection. The whale’s head is particularly large, constituting about a third of its total body length.
Killer Whale Predation
The primary natural predator of the bowhead whale is the killer whale, or orca. They hunt in coordinated groups to take down prey much larger than themselves. While attacks are not always successful, killer whales are the only predator in the Arctic capable of threatening an adult bowhead. Scars from their attacks are observed on many bowheads, suggesting these encounters are a regular part of their lives.
Orca hunting strategies are sophisticated. Pods work together to ram a bowhead to inflict internal injuries, or they may try to drown the whale by preventing it from surfacing for air. These hunts target younger calves or weakened individuals isolated from the group. The increasing duration of open-water seasons in the Arctic may lead to more frequent interactions between these two species.
Defensive Mechanisms
The bowhead whale has several defenses against attacks. Its size and power are a primary deterrent, as a healthy adult can weigh over 100 tons, making it a challenging target. The whale’s blubber, which can be nearly two feet thick, acts as a protective shield against impacts and orca teeth. This blubber layer is thicker than that of any other whale species.
The bowhead whale also actively uses its environment and strength to survive. It can use its bow-shaped skull to break through thick sea ice, creating an escape route where killer whales cannot easily follow. This association with sea ice is an anti-predator behavior. If cornered, a bowhead can use its large tail to deliver powerful blows to attackers.
Human Impact and Whaling
Historically, humans have been the most significant predator of the bowhead whale. From the 17th to the early 20th century, commercial whaling operations targeted bowheads for their valuable oil and baleen. Their slow speed and tendency to float when killed made them an ideal target, and unregulated whaling decimated global populations. By the 1920s, their worldwide abundance had plummeted to fewer than 3,000 individuals.
International protections and a moratorium on commercial whaling in the 20th century have allowed some populations to recover. The Western Arctic stock has shown considerable growth and is now the largest population in the world. Today, subsistence hunting by Indigenous communities continues on a managed and sustainable basis.