Whale Diversity

Whale Diversity

Whales are found in every single one of the world’s oceans, from polar seas, to tropical zones. They are even found in some of the freshwater lakes. Whales belong to a group known as the Cetaceans. The word ‘cetacean’ is from the Latin ‘Cetus’ which means ‘large sea creature’. It refers to over 93 different species of marine mammals that include all whales as well as their highly intelligent cousins, the dolphins and porpoises. The first whales originated about 50 million years ago. 

The order Cetacea contains animals like-

Cetaceans can be broken down into 2 groups. 

1. One that has teeth, known as Odontoceti. Creatures like Beluga Whales, Sperm Whales, Dolphins and Porpoises have teeth. 

2. The second group includes the filter feeders that have huge baleen in their mouth. They’re known as the Mysticeti. Animals like Humpbacks are Baleen whales.

Baby Humpback whales are called calves, but after they are 1 year old, they need to make the long migration from the poles to the equator all by themselves. 

Whales are related to Hippos or Sharks? - Whale history

Most people think that whales are related to sharks because both are marine animals, both are streamlined and both swim, but the huge difference is that Whales come to the surface of the water to breathe because they have lungs but sharks have gills, so they can stay underwater. Whales are warm-blooded, but sharks are cold-blooded. Also,

Whales = Mammals BUT Sharks = Fish

And Hippos are mammals. So Whales are mostly related to Hippos than to Sharks. 

The first whales originated about 50 million years ago. So if we look back at 50 million years ago, there were 4-legged furry land animals which we think took advantage of the aquatic environment. 

A little like crocodiles, we think that these furry animals got into the water, stayed submerged, possibly to exploit things in the water, possibly to grab things that come towards to feed themselves. This adapted the creatures to the water. Like, the nasal passages moved back up in the skull, the eyes moved across the skull so the organisms could stay submerged but see around clearly and little by little, the limbs started to become more amphibious to turn into an animal little like a hippo to stay in water and land at the same time and over about 8 million years, the hind limbs turned tail like and the forelimbs became more and more like ‘hydrofoils’ (lifting surface that operates in water) which made these organisms look more like Whales. But the thing is that those ancient animals didn’t have those blowholes and a big tail like present whales, but they evolved over time. 

SO THE THING IS THAT, WHALES ARE HIPPOS BEST FRIEND THAN SHARKS!

Baleens

The scientific name of Humpback whales is Megaptera Novaeangliae which means ‘big wings’ due to the fact that their ‘Pectoral Fins’ are the biggest size of any whale.

Those pectoral fins are super strong as well but not as strong as the muscles in their tails. Humpback whales get their common name from the ‘hump’ that they get when they dive and that muscle; the ‘Peduncle Muscle’ is the strongest muscle in the animal kingdom. That muscle helps them to breach out of the water, 40 tons as big a bus lurching out of the water! It is for sure a very strong muscle. 

Humpback whales are filter-feeders; they have about 400 plates of baleen that hang at the roofs of their mouths. They can filter out all of the krill and small fish they take in with huge gulps of water. 

These baleen plates are made up of the same material our fingernails and hair is made up of. It’s keratin. Their annual migration from the North Pole to Queensland in Australia takes about 6-8 months and during this time they don’t eat any food because the warmer waters don’t have much of the food that Humpbacks love, like krill. They will wait to go back to Antarctica to gorge on 1 ton of food every single day. Humpbacks communicate with a beautiful alien-like song, but only the male humpback whales sing. This song can change from year to year, from location and even from population. The males will sing these hauntingly beautiful songs for up to 30 minutes. Until they need to take a breath, they come to the surface, take a deep breath, dive back in and start all over again. It’s kind of like playing your favourite song on repeat all morning. Whales hunt in different ways, and the Humpback whale lunges into its prey and jumps at them and feeds on them. That lunging technique is known as lunge feeding. They lunge into swarms of krill with their mouths open. They all have a way to hunt with a bubble technique called bubble-netting.  

Bubble-Netting

Humpbacks are mostly found in Alaska. A group of whales work as a team to make bubbles and noise to trick their prey to the surface. 

A whale first searches for a group of small fish. Then it blows the water to produce some bubbles to confuse the fish. Then they make a noise that is unbearable for the fish and make them go up to the surface. When they reach the surface, the whales lunge into the school of fish with their mouths open and have a nice dinner.

Sperm Whale

One third of the Sperm Whale’s body is its head. Some Sperm whales can be 50 tons heavy and 20 meters long. They dive down to a depth of 2000 meters and can stay underwater for 1 hour. Sperm whales eat mostly squid. They go down 2000 meters so they need to find and hunt prey without light. They do this with a process called echolocation. They use sound to find where things are. They send out noise and when the noise echoes to them they can see the thing and find the prey and then they eat them up. But how do Sperm Whales go down 2000 meters? They have to dive down first. When they dive their lungs collapse and the air is blown in the space and that increases density and reduces buoyancy. They then glide down into the ocean. 

Whaling

Whales were captured for Whale Oil. The oil was pulled out from the whale’s head (from where it echo-locates) and that liquid was called ‘Spermaceti’. It was liquid wax found in whale heads. But Whaling was banned because of many people working to stop it. Whales were on the verge of extinction but after just a short time, whales returned.

Whales help to keep our oceans clean and healthy. How? Their manure does the job! Whale manure fertilizes the ocean and is a fuel for phytoplankton (marine algae) and the phytoplankton helps other marine animals to survive.

Why do whales matter?

Whales like Sperm Whales and Baleen whales draw carbon dioxide from the atmosphere and help us to fight climate change. These whales store tons of carbon in their fat.

CARBON SINK –WHALES AND CARBON STORAGE 

Just about 8 species of Baleen whales can sink 30,000 tons of carbon each and every year. 

But 3 countries – Iceland, Japan and Norway continue their whale hunts under scientific grounds. Entanglement in fishnets, it is estimated that 300,000 whales, dolphins and porpoises die each year. Ships sometimes go into the marine animals’ feeding ground or migratory routes. When a ship strikes a whale, it’s not the ship that loses. Not to mention that the noise that humans create disturbs their beautiful whale songs, confusing communication. Rising temperatures because of pollution from the industries and cities are changing whale migration routes, meaning that they may not find their feeding grounds. For whales, Plastic is not Fantastic. Currently over 11 million metric tons of plastic are flowing into the ocean each year. It was found that there were 135 plastic items inside One Sperm whale. These were predominantly plastic bags which may look like squid to a whale. The same thing happens with turtles. They think that plastic bags are jellyfish (jellyfish are turtles’ favourite food) and they eat them, causing buoyancy. 

North Atlantic right whales are the most endangered species of whales. They are large baleen whales of about 13 to 17 meters in length and they have white-yellowish patches on their heads.

Facts about the Indian Ocean

• The third largest ocean in the world, covering 19% of the water on Earth’s surface. 

• Known as the Indian Ocean since 1515. Before that, it was named Oceanus Orientalis Indicus (Indian Eastern Ocean). 

• It is located between Africa and Austral-Asia. 

• The deepest point is called the Java Trench. It goes down 7,258 meters. 

• Has the highest water temperature of any ocean. 

• It receives over 6,000 km of river run-off from the Ganges and Brahmaputra. 

• Has a submerged continent called Kerguelen Plateau, which was made up of volcanoes.

India has a huge range of biodiversity along its coastal communities.They rely on marine life so it needs to be protected at all costs.

Over 300 million tons of plastic is produced each year - yet only 9% of it is recycled.

Inevitably, a lot of the plastic waste ends up in the ocean and in the stomachs of fish and birds.

In recent years, the Indian and Australian governments have pledged to reduce plastic waste in the ocean. They’ll identify new technology and create circular models so plastic doesn’t go to waste, instead it gets reused and reused and reused.

Do you know your Blue Whales from your Bottlenose Dolphins?

Many species of sea life live in depths where there’s hardly light. They have to live by hearing what’s around them. It could be life or death as what is swimming near them, they could eat...or be eaten!

• Dolphins use sound to detect objects hundreds of yards away! Incredible!
• The pistol shrimp uses its claw to make compressed bolts of water to stun and kill prey.
• Whales use sound to communicate with each other, find each other and look for food.

Picture credit: Google