Dolphins are mammals which can inhabit both fresh and sea waters. They live in groups called pods and communicate using clicks and whistles. They surface out of water every twenty to thirty seconds to breathe. Some of them have the ability to stay underwater for up to 30 minutes. Their vision is strong which assists them in spotting predators or food over many miles.

There is an estimated 40 different species of dolphins in the world. These do not live in waters which can have below freezing levels, such as the freezing waters in the Antarctic and Arctic regions. These thrive in waters with temperature from10 to 20 degree Celsius. But the killer whale or orca, a species of dolphin, tends to inhabit the cold and frigid waters near the Antarctic and Arctic.

Of the total populace of dolphins, only 4 species live in fresh water. The dolphins are seen in all the five oceans and rivers as mentioned which makes them almost omnipresent in different waters across the world.

One of the most commonly found species is the bottlenose dolphin. Most people relate to this species on mentioning dolphin since they are seen in most dolphinariums. The bottle-nose species lives for almost forty to fifty years, while the other species have shorter life spans. This is attributed to the location of their habitat.

Bottlenose is seen in many waters like the Red Sea, Atlantic Ocean, Black Sea, Indian Ocean, Pacific Ocean and the Mediterranean Sea. These are seen in the ocean as well as close to the coastal regions.

The movement of dolphins is largely dependent on the availability of food. Hence, the bottlenose which remains along the coast and avoids migration since food in this region is always plentiful.

Most species which live offshore migrate in search of food. They encounter change not just in the type of food but the habitat as well. Dolphins can travel up to many hundreds of kilometers in pursuit of food. The route they follow is always well organized.

Humans have interfered with the eco-system by increasing the pollution levels in the environment, deforestation, contaminating the waters with wastes, hunting animals and marine lives excessively for the sheer joy or making use of the hunt in manufacturing products for our use.

Global warming has adversely affected the food chain of dolphins. Damage has been done in the migration cycles of dolphins too. There could be drastic changes in the pattern of migration and non-availability of food may force eve the non-migrating varieties to do so in an attempt to survive.

More Articles :

• Common Dolphins Habitat
• Do Wild Dolphins Migration ?
• Dolphin Natural Habitat
• Facts About Maui Dolphin
• Facts On The Dusky Dolphin
• How Many Amazon River Dolphins Are Left ?
• Lifecycle Of A Pacific Dolphin
• Types Of Dolphins
• What Do Dolphins Eat ?
• What Is Being Done To Protect Endangered Dolphins ?
• What Is Being Done To Save The Chinese White Dolphin ?
• What Kind Of Fish Do Dolphins Eat ?
• What Part Of The World Do Dolphins Live In ?
• Where Do Bottlenose Dolphins Live ?

Buzzle.com: Dolphin: Facts About Dolphins
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