Cetaceans - Frequently Asked Questions

1. What are the biggest and smallest whales in the world?
2. How fast can whales swim?
3. How does a whale breathe?
4. What causes the “blow” of a whale?
5. How deep can whales dive?
6. How do migrating whales know where they are going?
7. Why do whales strand?
8. Why do stranded whales usually die?
9. Why do whales breach?
10. How do scientists study whales in the wild?
11. How can I become a whale researcher?
12. What laws or regulations are in place in Canada to protect whales?
13. Does Canada allow commercial whaling?
14. How do I help protect whales?

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1. What are the biggest and smallest whales in the world?

The largest whale by far is the blue whale, which is also the biggest animal that has ever lived, including the dinosaurs. Blue whales in Antarctica are generally bigger than those in northern seas, reaching up to 30 meters and 160 tones. In other words, one whale can weigh about the same as 24 elephants! The smallest cetaceans are some of the coastal porpoises, which are rarely more than 2 meters and 45 kilograms.

2. How fast can whales swim?

Some dolphins and porpoises have been measured at speeds of more than 40 km/h over short distances. They may go even faster when pushed by the bow wave of a boat. Some of the large baleen whales aren’t exactly slowpokes either. Rorquals such as blue and sea whales can reach speeds of 30-35 km/h.

3. How does a whale breathe?

A whale breathes through one or two blowholes on the top of its head. When the whale is diving, a special structure known as a nasal plug stops water from coming into the blowhole. When the whale comes to the surface, muscles around the blowhole contract to open the nasal plug. The whale blows out old air and breathes in fresh air very quickly. The breath of a humpback whale, for example, can take only a few seconds. To do this, the whale blasts the old air out at more than 480 km/h! When we breathe, we usually replace only 25 per cent of the air in our lungs. But we don’t live in water. To get what they need, whales have to replace up to 90 per cent of their air supply with each breath.

4. What causes the “blow” of a whale?

Some people think the blow is caused by water from around the blowhole being forced into the air. It may be a bit more complicated than that. When warm air shoots out of the blowhole, it cools as it comes into contact with the outside air. This causes moisture droplets, or condensation, that we see as spray. It is also believed that the breath carries secretions from the whale’s respiratory tract. Whatever the explanation, there is nothing quite like the ripe and fishy smell of a whale’s breath!

5. How deep can whales dive?

The record for deep diving in whales belongs to the sperm whale as it searches for squid and deep water fish. Sperm whales have been found tangled in undersea cables at depths of 1,000 meters, and recorded by sonar at 2,000 meters. They may even go as deep as 3,000 meters. Sperm whale dives can last an hour or more, but another open ocean species, the bottlenose whale, is known to dive for up to two hours at a time.

6. How do migrating whales know where they are going?

No-one really knows. Perhaps they can recognize underwater landmarks or familiar water currents. They may use simple sonar, or passive hearing to hear sounds such as breaking surf. Or maybe they use some sense that we don’t have and therefore don’t understand. Some scientists think whales use the earth’s magnetic field to find their way. A compound called magnetite has been found in the brains of some whales, as well as in other animals known to travel great distances. Many long lines of magnetism have been found on the ocean floor. Migrating fin whales seem to follow these paths during their spring and fall migrations.

7. Why do whales strand?

This is another whale mystery. Many people have theories, but the truth is that we don’t know why large groups of whales will drive themselves up onto beaches. Even when towed back to sea, some whales will strand again. Stranding is most common among the very social toothed whales, such as pilot whales and certain dolphins and porpoises. Even killer whales can strand. One group of 20 came ashore on the west coast of Vancouver Island in 1945. They all died. Whales may strand because they are lost. Or perhaps one ill member of a group strands, and the others have followed. Necropsies of stranded whales have revealed that some were sick or injured. Some had parasite infections in their heads, perhaps making them confused. But many others seemed to have nothing wrong with them.

8. Why do stranded whales usually die?

Although whales breathe air, they are not adapted for life on land. In the ocean, a whale’s heavy body is supported by the water. On land, gravity takes over and the whale cannot breathe easily under the weight of its own body. As well, the same features which help keep the whale warm in water, work against it on land. It cannot lose heat fast enough and it begins to “cook” inside. Stranded whales are also vulnerable to sunburn and other skin problems related to being out of water for a long period of time. And stress is a big factor. Imagine how you would feel stranded in the sea for any length of time!

9. Why do whales breach?

Whales have many exciting behaviours. They can spy-hop by poking their heads out of the water, or tail-lob by smacking their flukes on the surface. There are many others, but perhaps the most breathtaking to see is a breach, when the whale jumps right out of the water. Only the whale knows for sure why it’s breaching, but we have a few theories. It may be signaling other whales nearby. It may be trying to knock off parasites, such as barnacles or lice. It could simply be taking a look around. Or maybe it’s just having fun!

10. How do scientists study whales in the wild?

Studying animals that live in the vast oceans and spend up to 95 per cent of their time underwater is not easy. Whaling used to be the source of most information. But those were dead whales. Today, we don’t need to kill or even capture whales to study them. We peek into their world using a number of techniques. Patient observation is the basic method — hours and hours of it, recording even the smallest detail. Photo-identification is another way. Killer whales, humpback whales, gray whales, and some dolphins are among the species that can be photographed and identified individually by markings, scars or colour patterns. To listen in to the noisy world of whales, researchers lower underwater microphones, or hydrophones, into the water. In some areas, such as Hawaii, researchers have special permits to take video film underwater. Some researchers in other parts of the world are trying various methods of tagging and radio tracking. Others are doing genetic studies using tiny skin samples shed or harmlessly removed from the whales. All of these techniques are designed so that the whales are disturbed as little as possible. Even whales that wash up dead on a beach can help us. Tissue samples can often give us details on such things as diet, parasites, and environmental toxins.

11. How can I become a whale researcher?

Study hard. But first be sure it’s what you really want. Being a whale researcher is not as glamorous as you often see on TV documentaries. It is not always sunny, warm and calm during field work, and whales can be very hard to find. Much time is spent in an office or lab analyzing data. And finding money to support research is often difficult. To be a biologist who specializes in whale research you must finish high school and go to university. Most whale researchers have at least a Bachelor of Science degree and many continue on to get a graduate degree (a Master’s or PhD) in biology. To get these degrees, you have to spend many years doing research under the guidance of experienced scientists. This helps you learn the special techniques used to study whales and their behaviours.

12. What laws or regulations are in place in Canada to protect whales?

In Canada, whales are protected by the Fisheries Act under the Marine Mammal Regulations. Some species also receive added protection through the Species at Risk Act.

13. Does Canada allow commercial whaling?

No. Canada stopped all commercial whaling in 1972 as a conservation measure. Some species of whales are hunted by Inuit in the north for food, social and ceremonial purposes.

14. How do I help protect whales?

Anything you do that helps to protect the environment is going to help protect whales. As we learn more about the needs of different whales and their habitats, we are better able to protect them. One way to help is to join conservation organizations who are funding or doing whale research. In many cases, you can also volunteer your time with these organizations. In this way, you will learn many new things while doing your part to protect whales and the environment in general. There is a lot of work to be done and every pair of hands counts! Check with your nearest library to find the names of some of these organizations.