Whales are some of the most fascinating animals on planet earth. They live in the ocean, but they also breathe air and give birth to live young. They are also some of the biggest animals living today. The blue whale, weighing up to 200 tons and measuring as long as 100 feet, is the largest animal in the world.
Due to their underwater habitats, whales are difficult to study. Therefore, scientists continue to learn more about these elusive creatures with the advancement of technology. Much of today’s research relies on radio tags, which are attached to a whale’s back, allowing scientists to track their movements via satellite.
What is the Average Lifespan of Whales
So, how long do whales live? Whales live an average of 40-70 years, depending on the species. Smaller species may have a life expectancy of 20 years, while larger species may reach 100 years.
Lifespan in Captivity
Whales in captivity have much lower life expectancies compared to their wild counterparts. For example, killer whales in captivity rarely live past their early twenties. On the other hand, wild specimens have been recorded to survive into their fifties and sixties.
Lifecycle of Whales
Although there are dozens of species of whales, they share some of the same characteristics when it comes to their life cycles. Many species follow a migratory pattern, feeding in cooler waters before traveling to warmer waters to mate.
Pregnant females have a gestational period of 10-17 months. Then, they will give birth to live young, called calves. Calves nurse on milk produced by their mothers for 1-2 years. Once they’re fully grown, calves may remain with their original pod or swim off to find one of their own. This will depend on the typical behavior of the whale species.
Causes of Death in Whales
Due to their massive size, whales don’t have many predators to fear. However, that doesn’t protect them from the other threats that are out there. There are multiple circumstances that can cut a whale’s life short.
Getting struck by ships or becoming tangled in fishing nets are the two most common human-related causes of whale death. Pollution and overfishing can also indirectly contribute to whale mortality by reducing the overall availability of food in the oceans, forcing whales to starve.
Beaching occurs when a whale swims into a shallow area and finds itself unable to retreat to deeper waters. Once a whale finds itself stuck, it has a few hours at most until it dies from drowning, suffocation, dehydration, or overheating.
Just like any other animal, whales can be vulnerable to illness and disease. Open wounds can become infected, causing premature whale death. Whales can also die from diseases they catch from other whales, from ingesting contaminated food, or from birthing complications.
Rising global temperatures and warmer oceans have led to toxic algae blooms, reduction of prey species, and loss of habitat, all of which impact whale life expectancies. Warmer currents can also influence whales’ migratory patterns, affecting birth rates or increasing the risk of beached whales.
Oldest Known Whale
The bowhead whale is known to be the longest-living mammal on earth with a life expectancy of over 200 years. This species of whale lives in cold Arctic waters, where it feeds on plankton, krill, and other small shellfish.
In 2019, Australian researchers sequenced the genome of the bowhead whale and estimated its “lifespan clock” to be an astonishing 268 years. Due to their longevity, bowhead whale DNA continues to be studied today.