How Much Do Whales Weigh?

Explaining exactly how much a whale weighs is quite a difficult question to answer because there are currently about 80 – 90 different species of cetacea and each species is a different size and weight.

First of all the cetacean species is divided into two groups known as the toothed whale and baleen whale suborders.

The large or great/true whales belong to the baleen whale suborder and possess baleen plates and bristles while those that are smaller and possess teeth are part of the toothed whale suborder.

All species of dolphin and porpoise also belong to the toothed whale suborder.

While we don’t have figures on every animal in the cetacean family luckily there are a few facts that can help clarify this topic, and at the end of the article we’ll share some stats regarding the weights of some of the most popular whale species on the planet.

To give you a better comparison first we’ll talk about the smallest and lightest of the whale species, the dwarf sperm whale.

The dwarf sperm whale gets its name from its small size and its spermaceti organ, which is located in its head and is believed to help it stabilize in the water, and yes this whale does belong to the sperm whale family which also consists of the sperm whale (the largest marine mammal in the toothed whale suborder).

This whale on average grows to be around 9 ft. long and when fully matured will weigh between 400 – 600 pounds.

In comparison the blue whale (the worlds largest living animal) can grow to a length of over 100 ft. and weigh in excess of 150 tons.

The blue whales heart alone can weigh as much if not more than a fully grown dwarf sperm whale.

In fact some of the largest blue whales have had hearts that weigh as much as 2,500 lbs., which is equivalent to the weight of a small car.

The blue whales name comes from the fact that when it is fully submerged in water it appears a purely blue color despite that fact that has a grayish blue skin tone when it isn’t submerged.

In general toothed whales are significantly smaller than their baleen whale counterparts with the exception of the incredibly large sperm whale.

To give you a few more comparisons here are some more statistics regarding size and weight of various whales:

  • The blue whale is the largest living animal on this planet and can grow to be over 90 ft. and weigh 150 tons or more.
  • The dwarf sperm whale is smallest of the whale species and can grow up to 9 ft. in length and weigh up to 600 pounds.
  • The sperm whale is the largest of the toothed whale suborder and can grow as long as 65 ft. and weigh over 62 short tons.
  • Baird’s beaked whale in comparison is the second largest of the toothed whale suborder and can grow to a length of 42 ft. and weigh around 15 tons.
  • The killer whale  “aka Orca” is actually a dolphin. In fact the killer whale happens to be the largest of the dolphin species (hence the name whale) and can grow to be larger than 25 ft. long and weigh over 6 tons.
  • Maui’s dolphin is considered the smallest marine mammal in the dolphin family as it can measure 4 – 6 ft. long and weigh between 95 – 115 lbs.

As you can see the length and weight of whales can vary significantly depending on its species.

Factors affecting a whales weight and size

When it comes to a whales overall weight there are a number of factors that help determine how much a whale will weigh.

Some of these factors include:

  • How healthy, genetically fit and large the whales parents were/are
  • Growth abnormalities – In some cases a whale may grow to an abnormally large size despite their genes
  • The thickness and density of the whales blubber (some whales have been observed to have as much as 40% of their total body weight made up of blubber
  • Whether or not food is abundant and easily obtainable in their environment
  • The types of foods that are available for consumption (cetaceans that live in different habitats may consume different prey)
  • The overall health and age of the whale

All of these varying factors can contribute significantly to the overall size and weight of a whale.

In fact whales of the same species have been known to have large differences in terms of size and weight.

For example the average size of a blue whale is 70 – 90 ft., however there have been cases of abnormally large blue whales measuring in at over 105 ft. long with an unconfirmed record of around 115 ft.

Other cetaceans have also noted for having large differences in size despite being of the same species and sex.

Size isn’t everything

The size and weight of a cetacean (whale, dolphin and porpoise) doesn’t necessarily determine its status in the food chain.

For example the killer whale which is a toothed whale and part of the dolphin family is smaller than many of the baleen whale species, however it is one of the only cetaceans known to hunt and kill other cetaceans including whales that are larger than them.

In fact despite the fact that baleen whales are typically larger than toothed whales the types of foods these marine mammals often consume are often made up of very small prey that can be significantly smaller than some of the foods toothed whales eat.

For instance the blue whale is the largest of the baleen whale suborder yet its primary diet consists of tiny krill that typically measure no more than 2 centimeters long.

The sperm whale on the other hand is the largest of the toothed whale species.

While these marine mammals are significantly smaller than the blue whale (20 – 50 ft. smaller) they are known for hunting and consuming large squid that can measure up to 40 ft. long.

One area where size may be important is in the area of being able to defend themselves or stave off attacks from potential.

Whales that aren’t particularly fast need to rely on their large size to protect them.

When a group of hungry killer whales is in the mood to attack a marine mammal they will often look for smaller weaker whales that can be easily defeated as opposed to trying to take down a behemoth sized whale.

Even thought their large size and weight may help deter predators it is often the ability to form a strong social group/network that helps prevent them from being successfully attacked rather than size alone.