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Blue Whale: Why Is It Endangered?

Are you aware there is an animal on Earth that is bigger than the largest dinosaur and longer than a full-size basketball court? This gigantic animal is the blue whale!

In our oceans today, there are approximately 10,000 and 25,000 blue whales. Although this may seem like plenty, blue whales are endangered. Today, blue whales are listed as endangered under the Endangered Species Act and protected under the Marine Mammal Protection Act.

This is because, since the late 1800s, many blue whales have perished because of human activities.

Blue whales are among the biggest animals that have ever existed on our planet. Their population has fallen by 98% over the past century due to human overfishing, whaling, pollution, and other reasons. 

  • Status: Endangered 
  • Known as: Blue Whale.
  • Estimated numbers left in the wild: 10,000 to 25,000.

Blue whales were first sighted by Europeans in 1758. But it wasn’t until 1904 that samples of whale organs were first recorded by marine biologists. They are currently listed as endangered by the International Union for Conservation of Nature (IUCN). 

Blue Whale

Let us take a closer look and discover why blue whales are endangered. And how people can help save these animals from extinction.


The Blue whale is the largest animal on Earth. It can grow as long as a Boeing 737-100 airplane (about 30 meters). They have grey and have a distinct mustache-like pattern.

Blue whales filter seawater through massive, slatted plates in their mouths, known as baleen. Large amounts of water are taken in and then squeezed out forcefully through the gaps in the baleen by their tongue.

It allows these massive creatures to harvest vast numbers of tiny animals called krill, similar to shrimp, which make up most of their diet. One adult whale has a feeding ability of around 3.6 tonnes of krill daily. A whale’s mouth can hold 90 tonnes of water, and its tongue weighs 2.7 tonnes.

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Blue Whale Population

The blue whale is not a common animal. Its population currently in the world is dangerously low and in grave danger due to various reasons.

Some reasons are ocean pollutionhabitat degradation, and being hunted by hungry humans. Whales have been going extinct for a long time, but it has been much worse recently.

Since the 1970s, the global blue whale population has dropped from 20 million to only 500. Their population decreased by 98% during that period.

See Related: What is Overfishing? Examples & Solutions to Prevent


Most blue whales are concentrated in most oceans, including the North Atlantic Ocean, the Eastern North Pacific, the Indian Ocean, and the Antarctic Ocean. Blue whales can only live in deep oceanic areas, preferring cold regions with abundant krill, except during breeding season, when they migrate closer to the equator.

See Related: Reasons Why Biodiversity Important to Ecosystems

Blue Whale Distribution

Blue whales migrate to different areas at different times of the year. They usually live in colder waters, but their migration depends on their summer feeding grounds and winter breeding grounds.

Role in the Ecosystem

Blue whales play a crucial role in the ecosystem as they recycle nutrients and oxygen. These creatures are a significant part of the marine ecosystem

They help balance the ocean’s ecosystems by eating krill and plankton. They eat about four tons of krill and plankton a day to help keep the population in check.

Blue whales are still part of the human food chain (and even the pet food chain) as they are hunted for meat and whale oil. Unfortunately, these events depopulated them because of commercial hunting before 1966. Other threats that endanger blue whales are vessel disturbance and fishing gear entanglements.

Blue Whale vs Other Whale Species

For starters, blue whales are much larger than other whales. They can range from 100 to 110 feet and weigh as much as 200 tons, while the next largest species are between 60 and 80 feet.

Blue whales are often confused with humpback whales, but they are different species. Humpback whales have huge mouths, humps under their heads, and long tails full of large baleen plates at the bottom.

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Blue Whale and Human Relationship

Blue whales and humans have had a relationship for centuries. Blue whales are known to be gentle, but they were hunted by humans who used their meat for food, their oil for lamps, and their bones for fashion.

With the outside possibility of these gentle giants tipping over small boats, these creatures don’t endanger humans. On the contrary, they are endangered because of humans. Human-whale conflict is a natural phenomenon in terms of humans’ tendency to corrupt nature.

Blue whales are social animals that like to communicate with each other by making loud noises, known as whalesong, which is why they’ve earned the title “bringers of joy.”

When blue whales try to feed near shore, humans often chase them away for both parties’ safety.

Blue whales have also been hit by ships so often that whale-watching vessels must be accompanied by an escort boat to prevent these species from being injured. They face many threats, making them go extinct quicker than the average animal.

Blue Whale SubSpecies

Blue Whale

There are five currently recognized subspecies of blue whales in the world’s oceans: the Pygmy, the Antarctic, the Northern, Northern Indian Ocean, and the Chilean subspecies. There are debates about the last one, but we will enlighten you more as we go on.

1. Pygmy Blue Whales (Balaenoptera musculus brevicauda)

Pygmy subspecies are much smaller than normal blue whales, weighing only 1.5 tons. They dominate other blue whale species based on population. 

They can be found in all oceans except for the Arctic Ocean. The Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region covers the conservation of their species.

2. Antarctic Blue Whales (Balaenoptera musculus intermedia)

The Antarctic blue whales are the largest subspecies of blue whales. They are also among the most endangered whales. 

The population of Antarctic whale species has decreased by 99%. It lives in the cold waters near Antarctica and eats small fish and krill.

3. Northern Blue Whales (Balaenoptera musculus Linnaeus)

The northern blue whale can be found in the North Atlantic, the Eastern North Pacific, and the Central/Western Pacific Oceans. Some of them stay in their areas for a year.

The Northern subspecies have a thick layer of blubber, which helps to keep it warm in the cold water. The Northern subspecies also have a dark gray color, which helps to camouflage it from predators.

4. Northern Indian Ocean Blue Whales (Balaenoptera musculus indica)

The Northern Indian Ocean blue whale subspecies are smaller than other blue whales. They are found in the northern Indian Ocean and are also darker in color.

5. Chilean Blue Whales (Balaenoptera musculus un-named subsp)

The Chilean blue whale subspecies is the smallest of the subspecies. They are found off the coast of Chile. It is not clear why this subspecies is smaller, but the smaller size may be an adaptation to the colder waters in Chile. Their genetics and geographic separation spark debates about their distinction.

Conservation Status

Whale Tail

Blue whales are an endangered species because 98% of their population was wiped out in the last century, mainly because of hunting. Blue whale populations have been able to recover since their commercial hunting ended through an international agreement in 1966.


Whale Poaching

Whale poaching is the illegal hunting of blue whales. It is a major contributor to the current decline in blue whale populations and ocean health.

The blue whale was immune to human whalers for centuries, thanks to its size, strength, and speed. The introduction of the harpoon gun in the 19th Century started the harvesting of this giant creature.

Over 300,000 killed blue whales were recorded before the 1966 ban, with the Soviet Union continuing illegal whaling into the 1970s and Japan continuing to hunt whales in the name of science. The main reason people poach whales is for their meat. 

Ship Accidents

Blue whales are often struck accidentally in shipping lanes, which can easily injure or kill them. Whales often collide with ships in the California Current – one of the whales’ favorite feeding grounds. They can also get tangled and strangled in fishing gear.

Water Pollution

One of the main threats to Blue whales is water pollution. This pollution can come from several sources, including oil spills, agricultural runoff, and chemical pollutants. These pollutants can seriously harm Blue whales and some cases, even kill them. They may be endangered further by alterations in krill populations due to global warming, heating the oceans, making it hard for krill to breed and live.

Ocean Noise

Ships give off noise pollution, which makes it difficult for whales to communicate with each other underwater. This can cause blue whales to beach themselves.

See Related: Dusky Shark

Conservation efforts

Conservation efforts to protect blue whales began in 1966 with the passage of the ban on commercial whaling. Attempts to conserve, restore, and study these gigantic marine mammals are ongoing. Both non-profit organizations and various governments are involved in efforts to foster their recovery. 

There is cooperation between countries to help conserve whales. The United States Fishery Management Plan is one of the most successful practices used for whale conservation, with 50% of blue whales located in the USA’s Exclusive Economic Zone (EEZ). Continued research into blue whales is also essential for blue whale conservation.

Whale Sanctuaries

Many conservation efforts to save whales are in progress. Some of these include creating whale sanctuaries, acoustic deterrents, and reducing ship collisions and noise pollution.

Whale sanctuaries are areas where blue whales can live without being disturbed. Acoustic deterrents emit sounds that scare whales away from areas.

Marine Mammal Science and Research Program

This program is the most comprehensive study on blue whales. The goal is to get an accurate count of the populations of blue whales, assess their distribution and migratory habits, and learn how they communicate with each other.

Educational Programs

Educational programs for whale conservation are for everyone. You can start such activities by researching whales and the issues of blue whales in the ocean.

Whale Watching Trips

Whale-watching trips are a great way to help whale conservation. It allows people to see these beautiful animals up close and learn more about them.

It will create awareness about the need to protect them and their habitat. Whale-watching trips also provide revenue for whale conservation efforts.

Pollution control

One of the main reasons why whales are endangered is because they are affected by pollution. There are many things that people can do to help reduce pollution and protect whales. Some include reducing plastic produced, driving less and using public transportation more, recycling, and composting.

Online Campaigns

Whale online campaigns are a great way to raise awareness about the endangered blue whale. Some of the things that you can do to help blue whales include:

  • Signing petitions to get these species protected
  • Sharing information about the whales on social media using hashtag #SavetheBWs
  • Donating money to organizations that are working to protect whales
  • Volunteering your time to help with whale conservation efforts


The Hebridean Whale & Dolphin Trust

The Hebridean Whale & Dolphin Trust monitors marine mammals and their habitats off the coast of Scotland. They protect various species through outreach and educational programs.

The Hebridean Whale & Dolphin Trust is a non-profit organization established in 2008. It aims to study, conserve and protect whales and dolphins. They operate through their two research vessels, The Sea Watch Foundation, Blue Ventures, and various networks promoting sustainable fishing practices.

World Wildlife Fund

The World Wildlife Fund is a global organization that conserves animals and their habitats. One of the main focuses of WWF is the conservation of blue whales. They protect whales by developing partnerships with governments, businesses, and other organizations.

One of their ways is by teaching whalers how to use new technologies. Whaling used to be a way for people to survive, but today it is not needed as the WWF introduced more sustainable fishing practices to whalers.



Why are blue whales endangered?

Blue whales are endangered because they’ve been hunted by humans for their oil, meat, and teeth. They are also at risk from commercial fishing and shipping, as well as pollution.

Is the blue whale friendly to humans?

Blue whales are not classified as aggressive species. They have been observed to follow fishing boats around. The whales can weigh as much as 200 tons and grow as long as 100 feet! They also emit a wide range of sounds from low-frequency moans to high-pitched whistles, where the frequency is modulated by their breathing patterns.

How can I help blue whale conservation efforts?

As whales face the threat of extinction due to modern technology, you can help whale conservation efforts by being more conscious about the environmental impact your technology usage has on whales. There are many ways to help whales directly affected by the noise in the ocean. 

Our oceans are becoming noisier with boat traffic, sonar, and other tech usages. It will compromise the blue whales’ ability to communicate effectively with each other.

Why are whales becoming endangered?

Whales are becoming endangered due to a variety of human activities such as commercial whaling, pollution, and climate change. These activities have led to a decline in whale populations and threaten their survival. Additionally, some whale species are more vulnerable to these threats than others, making conservation efforts crucial to protect their populations.

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