Animal stories: Dolphins

Dolphins are a very social animals and are considered one of the most intelligent aquatic mammals. They are well known for their friendly nature and playful attitude. They have a long, beaklike snout, a sickle-shaped dorsal fin and broad flippers. Like cows, they have two stomachs — one for storing food and one for digesting it.

They grow upto 12 feet and sometimes, weighing more than 1,400 pounds. They can dive 1,000 feet under water and can jump up to 20 feet out of the water. Dolphins breathe at the surface of the water through single blowwhole every two minutes. Their blow is a single, explosive cloud.

They make a variety of very high-pitched squeals, whistles and whines. These noises are most likely used to communicate with each other. They can also swim very fast. Dolphins have very little sense of smell and their skin is extremely delicate and easily injured by rough surfaces much like human skin.

Hunting styles

Dolphin’s hunting strategies are varied and diverse. They often cooperate with each other when hunting and catching fish. In open waters, a dolphin pod sometimes encircles a large school of fish and herds them into a small, dense mass. Then they take turns charging through the school to feed. To hunt larger fishes, they may use their tail flukes to kick a fish out of the water, then retrieve the stunned prey. They break larger fish by shaking them or rubbing them on the ocean floor.

Their home

Dolphins are found worldwide. They mostly live in harbours, bays, gulfs and rivers. The common dolphin can be found widely distributed in all tropical sub-tropical and warm-temperate waters. They migrate if the water gets cold or the fish supply and feeding habits change. Some like cold and deeper water than others. They are found in the Mediterranean and Black Seas, the Red Sea and Persian Gulf. The long-beaked common dolphin is more often found in coastal waters whereas the short-beaked common dolphin is seen more frequently in offshore areas. Dolphins live in small pods. These pods range from 1,000-100,000 individuals.

Favourite food

Dolphins are carnivores and mostly eat fishes and squids. They eat approximately 4-5 per cent of their body weight in food per day. Dolphins do not chew their food. Usually they swallow fish whole, head first, so the spines of the fish won’t catch in their throats. Dolphins often like to hang out near local fishing areas, feeding on fish that escape nets or fish discarded by fishermen. Dolphins also feed on other marine animals like octopuses. Their feeding behaviour is flexible and adapted according to the habitat and available food resources.

Young ones

Dolphin calves are born in the water. Unlike any other mammal, dolphin babies are born tail first. Sometimes an assisting dolphin may stay close to the new mother and the baby dolphin. This assisting dolphin is called as an ‘auntie’ dolphin. But, it may be male or female dolphin. A mother dolphin only allows this auntie dolphin near her calf. Dolphin calves are approximately 106-132 cm long and weigh about 20 kg. In the first few days after birth, the dorsal fin and tail flukes are flaccid and pliable, but gradually become stiffer. Calves are darker than adults. A mother dolphin will stay with a calf for two to three years. They will start to eat fish at approximately six months of age. Dolphins have a maximum life span of about 25 years. — Compiled by Merina Pradhan