Getting to Know Dolphin Facts with IPB University Professor of Fisheries

Dolphins are aquatic animals that are quite close to humans. Professor of the Faculty of Fisheries and Marine Sciences, IPB University, Prof. Yusli Wardiatno, shared some facts regarding dolphins.

According to Prof. Yusli, currently there are 49 species of dolphins with 42 types of dolphins and seven types of porpoises. In Indonesia alone there are 16 types. Among them are the Striped Dolphin (Stenella coeruleoalba), Fraser Dolphin (Lagenodelphis hosei), Rough-toothed Dolphin (Steno bredanensis), Common Bottlenose Dolphin (Tursiops truncatus), Indo-Pacific Bottlenose Dolphin (Tursiops aduncus), Long-beaked, Common Dolphin (Delphinus capensis), Spinner Dolphin (Stenella longirostris), Indo-Pacific Humpback Dolphin (Sousa chinensis), Risso's Dolphin (Grampus griseus), Spotted Dolphin (Stenella attenuata), Melon-headed Whale (Peponocephala electra), Killer Whale (Orcinus orca), Pygmy Killer Whale (Feresa attenuata), False Killer Whale (Pseudorca crassidens), Short-finned Pilot Whale (Globicephala macrorhynchus), and Irrawaddy Dolphin (Orcaella brevirostris).

"Orcas (killer whales) are the largest dolphins, Hector's and Franciscana's dolphins are the two smallest," said the IPB University Aquatic Biologist.

Although dolphins are always called “fish”, dolphins are actually mammals that suckle their young and breathe using lungs. Therefore, they must come to the surface of the water to breathe air and give birth. Dolphin pregnancy lasts from nine to sixteen months. The offspring of the Orca dolphin will live with their mother for life.

The maximum lifespan of dolphins varies from about 20 years in the smaller dolphin species, to 80 years or more for larger dolphins such as the orca.
Dolphins eat fish, squid and crustaceans. They have conical teeth, with a number of between 14 – 240 teeth depending on the type. Even so, they do not chew their food but break it into small pieces before being swallowed.

In eating behavior, dolphins will swallow fish from the side of the head first so that the fish spines do not get stuck in the throat. When hunting, dolphins produce bubbles to bring their prey to the surface.

"They sometimes also use a hunting technique called 'fish-whacking', which is to use their tail to hit the fish and make them faint and easier to catch," said this teaching staff at the Department of Aquatic Resources Management, IPB University.

Known to have intelligence above the average animal in general, dolphins have an attractive sound resembling a whistle or a scream.

This sound is used for well-developed communication and echolocation. In addition to good communication skills, dolphins, particularly the bottlenose types, are one of the few species, along with apes and humans, that have the ability to recognize themselves in a mirror. Bottlenose dolphins also have the ability to sleep by activating half of their brains and keeping their eyes open.

"This behavior is an attempt to monitor the group to stay united and to identify the presence of predators in an effort to avoid them," added Prof Yusli.

The Maui dolphin is the most endangered dolphin. There are fewer than 50 individuals left, and less than 10 vaquitas (porpoise species) survive. Noise pollution and fishing gear such as nets are a threat to the dolphin's environment. (*/zul) (IAAS/IRN)


Published Date : 16-Jul-2021

Resource Person : Prof Yusli Wardiatno

Keyword : Lecturer of IPB, IPB University, Dolphins, Department of Aquatic Resources Management of IPB