WHALE WONDERS: 13 INTERESTING WHALE FACTS

From epic migrations to whale songs and the vital role these marine giants play in keeping our oceans healthy, dive into the wonderful world of whales!

They may be hard to spot from land, but these elusive gentle giants come in all shapes, sizes and colours and can be found across the globe. Some live in groups, some are solitary, but they all play a vital role in keeping our oceans and planet healthy.

Whales at a glance: quick facts

• The Antarctic blue whale is the largest animal ever known to have lived on Earth.
• Some whales can dive more than two kilometres below the surface and remain there for over an hour.
• Whales communicate using body language and a range of sounds, including clicks, whistles and songs.
• There are over 90 species of whales, dolphins and porpoises worldwide, with around 45 in Australian waters.

1. Are whales mammals or fish?

Warm-blooded and air-breathing, whales are mammals, unlike most of the ocean’s cold-blooded residents. As marine mammals, they give birth to live young instead of laying eggs like most fish. Rather than having gills, whales breathe air when surfacing through a blowhole at the top of their heads. Baleen whales have two holes while toothed whales have one.

2. What exactly is a whale?

In fact, the term ‘whale’ isn’t a formal scientific category. All whales, dolphins and porpoises belong to a group of marine mammals called ‘cetaceans’, which are scientifically divided into toothed whales and baleen whales. In everyday language, however, ‘whale’ usually refers to the larger species such as humpbacks, sperm whales and blue whales.

3. What’s the biggest whale?

The Antarctic blue whale is the largest animal to have ever lived on Earth. Reaching up to 33m in length, blue whales tip the scales, weighing up to 180,000kg – roughly the same as 33 elephants! These marine giants migrate between frigid polar seas and warm tropical waters, with the largest animals estimated to eat up to 6 tonnes of krill per day – about the weight of a small truck.

4. How do whales sleep?

Because whales (and dolphins) must consciously surface to breathe, they rest one half of their brain at a time when sleeping. This is called unihemispheric slow-wave sleep – a bit of a mouthful, but an extraordinary adaptation. If whales were to completely shut down their brain while they sleep, they would risk drowning. Most large whales lie horizontally at the surface to rest, a behaviour commonly called logging. Sperm whales have a fascinating routine and float vertically near the surface to get some shut-eye.

5. Is it true that some whales have teeth and some don't?

Cetaceans fall into two main groups: toothed and baleen. Only toothed whales – such as the sperm whale – have teeth, and only on their bottom jaw. On the other hand (or flipper), baleen whales have hundreds of ‘baleen plates’ lining their upper jaws. These plates are made of keratin, the same material our hair and nails are made from. Soft bristles line the inner edge of the plates, acting like a sieve to filter small prey, such as krill and plankton. The fin whale, one of many baleen whales found in Australia, boasts up to 480 baleen bristles.

6. How do whales communicate?

Using a combination of clicks, whistles and songs, whales can communicate across vast distances. Each vocalisation serves a distinct purpose, from navigation to socialising. Whales living in pods even have their own ‘dialect’ to help differentiate between their own pod and others. Blue whales set the world record for the loudest animal on Earth, reaching up to 180 decibels – that’s as loud as a jet plane! Researchers believe that some whale songs can travel between groups separated by nearly 8,000km.

Communication also takes place through body language. Breaching, tail slapping and flipper slapping are all common behaviours that help whales interact and socialise. Keep an eye out for these displays in the water next time you’re whale watching to witness whale communication in action!

7. Are some whales better divers than others?

Not all species are built for extreme diving, with most whales spending much of their time within a few hundred metres of the surface. However, sperm whales are expert divers known to submerge to depths of two kilometres for up to 60 minutes, hunting for prey such as giant squid. Cuvier’s beaked whales can go even further, with recorded dives approaching three kilometres and lasting almost three and a quarter hours.

8. How do whales keep our atmosphere healthy and support the generation of oxygen?

By recycling nutrients and storing carbon, whales play a critical role in keeping our planet healthy. For instance, whales feed at depth and release their nutrient-rich waste near the surface, helping to fertilise microscopic phytoplankton. This process is crucial, as phytoplankton generate over half of Earth’s oxygen and absorb large amounts of carbon dioxide. It is thought these gentle giants help capture a huge amount of carbon over their lifetime.

For most land animals, the carbon stored in their bodies is gradually released back into the atmosphere after death. However, when whales die, they descend to the seabed, and as they settle there, so does the carbon stored inside them. As the whale carcass is slowly consumed by deep-sea organisms, some of this carbon is cycled through the ocean ecosystem. The remainder stays at the depths of the ocean floor for centuries in a phenomenon known as ‘blue carbon’.

Find out how WWF-Australia is working to protect whales and the oceans they help sustain.

9. Do whales have multiple stomachs?

Whales have specialised digestive systems, and most have four distinct stomach chambers. Some species boast an even more complex stomach structure, such as beaked whales, which can have up to 14 stomach compartments! These different chambers help whales swallow food whole, break down tough prey and extract nutrients from it.

10. Are orcas whales or dolphins?

Orcas are ‘toothed whales’ and are the largest members of the dolphin family. Highly intelligent, with sleek, curved bodies and agile manoeuvres, orcas share many physical and behavioural traits with other dolphins, including the common bottlenose dolphin. Orcas live in pods, and work together using calculated hunting tactics, earning them their title as one of the ocean’s top predators.

11. How do whales raise their young?

Whale pregnancies last an average of 10-18 months, after which calves stay close to their mothers for protection and care. Whales feed their young milk, and calves rely on this as their main food source during early development. Pods also contribute to upbringing, teaching vital skills such as hunting and communication. Calves stay with their mothers for an average of one year before becoming independent, and depending on the species, juvenile males can join other pods (including ‘bachelor pods’ with other young juveniles)!

12. Are whales threatened around the world?

Increasing threats to whales from human activity mean seven out of fourteen great whale species are now classed as endangered or vulnerable. In Australia, whales face dangers such as ship strikes, bycatch (accidental entanglement in fishing gear), chemical, plastic and noise pollution, and climate change, which impacts their food supply. Every year, about 300,000 whales, dolphins and porpoises perish globally due to fishing gear entanglement alone. Whales play an important role in maintaining healthy marine ecosystems, so we need to do all we can now to safeguard their future.

Here’s how you can help protect whales and their ocean home.

13. What are ‘blue corridors’?

Blue corridors are the migratory routes whales follow as they move between the places where they feed, breed, raise their young and socialise. Many species travel the same paths each year from Antarctic feeding areas and along Australia’s east and west coasts. Whales rely on these critical habitats and the ocean pathways that connect them for survival. Unfortunately, these pathways often overlap with human activity, putting whale populations at risk.

WWF and our partners have used scientific evidence from years of satellite tracking data to map these ‘blue corridors’ around the world. By integrating this with the information we have on threats to whales, we can help governments identify solutions and create effective policies to protect critical whale habitats.

You can explore the blue corridors and the threats whales face in our oceans using this interactive Blue Corridors map.

What is WWF doing to protect whales?

WWF-Australia is working to protect whales by advocating for better ocean protections and we are already seeing real momentum. It’s time to care for the oceans that care for us.

We strongly support the government’s commitment to protect 30% of Australia’s oceans as marine sanctuaries by 2030. But it is critical that these sanctuaries be placed in areas with the greatest impact. As the government reviews how Australia's marine parks are managed throughout 2026, WWF-Australia will share its expertise and scientific research to guide decision-makers on where protections will be most effective.

As part of this process, we are calling on the Australian Government to safeguard blue corridors and protect whales on their migration routes.

This government’s commitment is part of an exciting global pledge, with nearly every country recognising that looking after our natural world plays a powerful role in tackling climate change, as healthy ecosystems store carbon and keep our planet in balance.

In March 2026, Australia joined the High Seas Treaty, along with 90 other countries. This is a great step forward for ocean protection as it allows countries to propose protected areas, such as marine sanctuaries, outside national borders. But there is still a lot of work to be done. Together, we have a once-in-a-generation opportunity to strengthen ocean protections and secure a safer future for whales and other marine animals.