In the Delphinidae, or dolphin, family, bottlenose dolphins are the friendliest, among the most studied, and are the ones seen in dolphin encounter programs, marine parks and movies such as “Flipper.” Children, often attracted to these social mammals, enjoy learning about the commonalities and differences between dolphins and people. The dolphin can be considered the ambassador of the sea because its popularity has inspired many people to learn more about its oceanic environment. Bottlenose dolphins live around the world in temperate and tropical waters, near and far from shore.
Beauty and Brains
Although intelligence can't be measured the same in dolphins as it is humans, bottlenose dolphins are quick studies, according to zoologist Anuschka de Rohan. Most scientists believe bottlenose dolphins learn complicated language-like commands and are at least as smart as chimpanzees and dogs, reports an article in "Scholastic Magazine." Their name comes from the bottle-like shape of their beaks. Their sleek bodies, soft to the touch, are gray and silver, with pink on the underside. Adult bottlenose average 7 to 12 feet long and weigh from 600 to 1,400 pounds, with the males being larger. Their weight doesn’t hold them down, though. They leap as high as 20 feet and clock speeds up to 25 mph. Females live up to 50 years and males up to 45, according to the National Marine Fisheries Service.
Like humans, dolphins often show affection with cuddles, pats and strokes. In their nursery, the adult and adolescent males watch over the mothers with their calves. And when a dolphin is injured or ill, others try to help it, according to National Geographic – Kids. Some bottlenose dolphins have helped humans and other animals. In the news once in a while you hear about a dolphin helping an injured human to shore. But dolphins can play too rough -- after all, they are wild animals. And while mostly dolphins care for each other, sometimes some of them fight.
Communication and Play
Bottlenose dolphins communicate vocally with whistles and squeaks, through nasal sacs. You could say they talk through their noses. They also have a signature whistle, according to a "Discovery News" article that reported in February 2013 on a study led by Stephanie King of the University of St. Andrews Sea Mammal Research Unit. They also use body language, such as a slap of the tail. With body language and sounds, they express emotion, keep track of each other, and warn and alert each other. Dolphins are playful and enjoy many games. According to the National Wildlife Federation, some of the games involve imitating one another, such as a game similar to pat-a-cake: Two dolphins take turns swimming underneath one another, touching their pectoral fins, back and forth. Playing catch with a string of seaweed or a bubble is a favorite sport. So is tag.
Bottlenose dolphins use a variety of strategies to catch food, hunting individually or working together. They eat fish, squid and a variety of invertebrates. Usually they swim in pairs or groups of a dozen or so called pods. But to capture a large school of fish, they form a herd of sometimes hundreds. They encircle the fish. As they tighten the circle, they also take turns snapping up fish, according to National Geographic Kids. First, though, they must find the fish. To do this, they use echolocation. The dolphin sends a high-frequency sound pulse. The sound pulse traveling through the water, hits an object, and then the echo bounces back to the dolphin. The type and speed of the echo helps the dolphin identify what its sound pulse hit.
After all the hunting, socializing and playing, dolphins need to rest. The pod enjoys a quiet time while the calves nurse, and then prepare for sleep. Their sleep is different from the sleep of humans and other animals. A dolphin must surface to breath air, and it must be conscious to do this. So one side of its brains sleeps while the other side gets it to the surface and breathes, according to a 1998 article in "Scientific American" by Bruce Hecker, director of husbandry at the South Carolina Aquarium. Pairs of dolphins have been known to synchronize their breathing, and in their deep state of rest, gracefully rise to the surface as one, breath, float back down and then continue this pattern, until they awaken. Spinner dolphins, which have a tighter social structure than bottlenose dolphins, can actually breathe and sleep in sync as one pod, according to the Wild Dolphin Foundation.
- Scholastic: All About Dolphins
- National Geographic – Kids: Bottlenose Dolphins
- NOAA Fisheries – Office Of Protected Resources: Bottlenose Dolphin
- The Guardian: Why Dolphins Are Deep Thinkers
- Scientific American: How Whales And Dolphins Sleep
- Wild Dolphin Foundation: Spinner Dolphins
- Discovery News: Dolphins Call Each Other By Name
- National Wildlife Federation -- Ranger Rick: Dolphins
- Animal Planet: Dolphins
- Medioimages/Photodisc/Photodisc/Getty Images