Amazon river dolphin

Amazon river dolphin at Duisburg Zoo

The Amazon river dolphin ( Inia geoffrensis ), also known as Boto, is a common South American river dolphin. The also occurring in the Amazon Sotalia is a representative of the actual dolphins.

• 4.1 mythology
• 4.2 entertainment in zoos

Properties

Appearance

Amazon dolphins are 2 to 3 feet long. Their color varies with age: young animals are silver-gray, older Amazonian dolphins are pink. The head is rounded, clearly separated the long snout of him. The eyes are tiny and stunted, but are still functional. Unique among all river dolphins is the hair on the muzzle which is covered with stiff bristles. It reaches an average weight of 85 to 160 kilograms. His neck vertebrae are not fused, which makes it especially portable. His shoulder joint is not fused in the typical manner for whales and dolphins. A special feature of the Amazon dolphin is that his teeth does not consist of homogeneous teeth, but the rear of the snout much wider teeth are present. These facilitate the chewing large prey fish and the breaking of tanks.

Way of life

As a maverick animal of the Amazon river dolphin is rarely seen together with conspecifics. He avoids the large currents and adheres preferably in the swampy, standing side arms. Here he does not need its already stunted sense of sight, but relies entirely on echolocation in search of its prey, which consists mainly of small fish. Amazon dolphins appear only briefly and come about every thirty seconds to catch your breath at the surface. They are less active than oceanic dolphins and perform as good as never jumps.

Dissemination

There are three distinct populations, all of which are common in the northern half of South America:

• I. g geoffrensis, in the Amazon, and many of its tributaries
• I. g humboldtiana, also called Tonina, in the Orinoco and its tributaries
• I. g boliviensis, in the headwaters of the Rio Madeira, which is a tributary of the Amazon, but through a series of rapids and waterfalls separated from this. This population is now considered a separate species, which was isolated from I. geoffrensis before about 2.8 million years ago.

Among the river dolphins of the Amazon river dolphin is considered the least endangered species Nevertheless, it is guided by the IUCN as endangered. He occasionally gets caught in fishing nets or falls by his curiosity in ship propellers. Regionally, it is killed by fishermen, who see him as a rival when fishing. Also by dams and river pollution of the Amazon river dolphin is potentially at risk.

Designation

This dolphin to bear the common name, Amazon river dolphin still a number of other names. In German, the form Amazon River dolphin is known that only describes the habitat. Common forms are the Boto, Tonina Bofeo or that originate from the Amazon region. From the English variants Amazon River Dolphin, Pink River Dolphin, Pink Dolphin, Pink Freshwater Dolphin and Porpoise Pink are known. Other variations include Dauphin de l' Amazone, Boto Cor - de-rosa and Boto Vermelho. All names are available for the Amazon river dolphin Inia geoffrensis.

System

The systematics of river dolphins is controversial. While previously all members of this group were considered to be convergent and not related to each other, one goes after molecular genetic studies now assume that the La Plata dolphin and probably also the possibly already extinct Yangtze River dolphin are related to the Amazon river dolphin and a common family, Iniidae form.

Others

Mythology

For some indigenous peoples, the belief holds that a drowned man to a river dolphin is. The river dolphin reserves in this new life, the ability to transform occasional shore leave back into a human.

Some people on the Rio Negro believe that the Amazon river dolphin at night as a handsome young man in white suit comes with hat on land and on the lookout for young girls. Therefore any strange young man is first considered suspicious. The so turned dolphin seduces the young girl and then disappears the next morning in the river as a dolphin. The girl becomes pregnant and eventually the child is born. There really are birth certificates, in which named as the father " Boto Cor de Rosa".

Entertainment in zoos

In aquariums Amazon dolphins are held outside of Venezuela since 1975 only in the Duisburg Zoo. Died in 2006, the Duisburg animal Apure over the age of 40 years of old age. At the Duisburg Zoo now lives only a copy of the Amazon dolphin named Butu.