About the wisdom of children (part five)

Text: Edeltraud Konradt; photos: firmm + see reference

Perhaps you have already read the other blogs in this series. Here are the best questions from 2022:

Dinos eat blue whales,

this statement came with full conviction.
No, this is not true.

Dinosaurs were long extinct when some ungulates began to evolve from land animals to marine mammals in the Eocene 30-40 million years ago.

What is a tuna?

Tuna are closely related to bonito and mackerel and belong to the mackerel family (Scombridae) and thus to the order of Perciformes with nearly 10,000 species. Tuna can reach speeds of up to 80 km/h over short distances. They are found both near the coast and in the open seas, in water depths of up to 1000 metres, and live in all polar oceans. They are highly endangered because their populations have declined by up to 90% worldwide (source WWF). They are highly migratory schooling fish that travel thousands of kilometres a year. However, bluefin tunas have only two regular spawning grounds, in the Gulf of Mexico and in the Mediterranean Sea.
The picture shows the largest tuna caught in the Strait of Gibraltar. Bluefin tuna can grow to over 4 metres and weigh over 600 kg.

That's a penguin dolphin ...

… shouted a boy of about 7 years and pointed at the small Common Dolphin.

No, of course it isn't.
Penguin dolphins do not exist. The boy mistook the picture of the little Common Dolphin for a king penguin.

Are there sharks in the Strait of Gibraltar?

Yes, there are.

According to Wikipedia, there are 30 species in the Mediterranean, with such exotic names as Kitefin Shark (Dalatias licha), Longnose Spurdog (Squalus blainvillei), Sawback Angelshark, Smalltooth Sand Tiger (Odontaspis ferox), Blue Shark (Prionace glauca), White Shark (Carcharodon carcharias) and many more. How many of these also reside temporarily or permanently in the Strait of Gibraltar is unclear.

What do dolphins do all day, do they have a job?

Well, they keep themselves busy in a different sense.
They are searching for food, unlike us humans. We find our food on the shelves in the supermarket.
Dolphins have to look for their food in the vastness of the seas. This takes a lot of time and skilful teamwork, which is the only way they can find their food.
The parents and other members of the group - also called the school - raise their young, teach them how to catch fish, what methods to use to get the food. In this way they learn about hunting grounds and hunting techniques.
The young animals also learn their language from the adults. How to deal with each other, help each other, look out for each other, respect each other. In other words, everything is almost the same as with us humans.

What do dolphins do in the winter?

Dolphins live their whole lives in the sea. At different times of the year, at different temperatures, sometimes it is rougher and colder. The skin with the blubber underneath (more precisely, the blubber layer lies under the dermis and above it is the epidermis) is optimally adapted to the different conditions in the sea. When the surface of the sea is wavy and rough, like during a storm, whales and dolphins dive deeper. Strong swells don't bother them. Rather, they enjoy the weather, as they can surf superbly in the big waves.

How do dolphin babies drink?

Their mothers have two skin folds at the back of their bodies, each containing a mammary gland. The skin fold opens, and the mother whale squirts the milk in a powerful jet into the open mouth of the baby dolphin. Whale milk is the most nutritious, containing 42% fat and 12% protein. It is thick and creamy, so it hardly mixes with the seawater.

Do dolphins also have a mum and a dad?

But yes, otherwise they wouldn't have been born at all.

However, dolphin families are not together like we humans are as a classic nuclear family with father, mother, and children. In the case of dolphins, there are many, many dolphins. They form an extended family - so-called schools. The mother feeds the baby dolphin and teaches the young animal everything it needs to learn for life. The dolphin's dad is not involved in this. The young animals also form their own little schools - dolphin kindergarten schools - where the young animals get together to play, to measure forces, to practise being together. Just like human children learn social behaviour in kindergarten.

Are there still many Blue Whales?

Due to heavy hunting in the 20th century, the Blue Whale was almost wiped out. Even today, it is still threatened with extinction, although hunting is banned. According to the IUCN, there are an estimated 10,000 to 25,000 animals left today. Their habitat are all oceans.

They are the giants of the seas with a length of up to 33 metres, and 200 tonnes in weight. They owe their name to their body colouring. They feed on krill (shrimps) and small fish.

Why are there no more Blue Whales in the Strait of Gibraltar?

Well, there was a whaling station in Algeciras from 1921 to 1960. The Blue Whales living here were also hunted and processed there.

What is krill?

Krill are small crustaceans (they are part of the zooplankton). They occur in huge shoals. Around 80 different species of crustaceans are counted as krill.

What is a sunfish?

It is considered the heaviest bony fish in the world. It can reach a length of 3.30 metres and a weight of 2.3 tonnes. It is not only found here in the Strait of Gibraltar, but also in the Mediterranean Sea, the North Sea, and the Atlantic Ocean. Its body is discus-shaped and hardly longer than high, it does not have a tail fin. Sunfish feed on jellyfish, plankton, small fish, and other marine animals.

Photo credits:

King Pinguin – spektrum.de/© TANE-MAHUTA / GETTY IMAGES / ISTOCK (AUSSCHNITT)
Blue Shark: Wikipedia
Blue Whale: blog.wwf.de / Animation © bbevren / iStock / Getty Images
Krill: GettyImages-535093478_Peter-JohnsonCorbisVCG