The bottlenose dolphin is a mammal that has piqued the interest of scientific research for a long time. You can see the dolphins at many aquatic shows, but they are found in temperate waters. You might see one because these dolphins tend to enjoy staying close to shore. They get their name from the shape of their elongated upper and lower jaws rostrum or snout. Dolphins don’t breathe near their rostrum. They have a blowhole on top of their head, which they use to breathe. Dolphins can reach lengths just over four meters or 13 feet, and their average weight is 660 pounds. They are grey, but this color ranges for each dolphin. Around their upper fin and rostrum, their color is sometimes almost black, and their stomachs range from light grey to white.
Echolocation for hunting
Dolphins have one of the highest encephalization quotients, their brain size compared to the average of an animal of their size, of any animal on earth. Their complex brains make them capable of understanding artificial languages, communication, memory, self-recognition, mimicry, and other impressive feats. One interesting behavior of the dolphin is their use of echolocation. They can emit over 1,000 click noises per second, and these sounds travel until they hit something, like prey, and send back information to the dolphin. Echolocation helps them determine the size, shape, distance, and location of the object. Dolphins mainly seek low-dwelling fish to eat, but they will also eat squid and shrimp. When the dolphin finds the food, they will use their teeth to hold the prey steady, and then they will swallow the fish in one gulp, head first.
Other behaviors
Dolphins have been known to creatively problem-solve ways to eat as much food as possible. One example of this behavior is herding, where the dolphins will group a school of fish and then pass back and forth in turns to eat them. Another interesting dolphin behavior is how they sleep-swim. It may look like they are traveling while they are sleeping, but they are in a half-sleep. One side of the brain is shut down while the other monitors breathing and surfacing. The sleeping cycle lasts for around eight hours with increments from a few minutes to a few hours. They occasionally sleep with one eye closed. Dolphins also are voluntary breathers. They swim near the surface of the water so they can open their blowholes to get some air. They do this about two to three times a minute, even though they could stay submerged for up to 20 minutes. Because they breathe through the usually closed blowhole, they have a pretty bad smell, though they have fantastic eyesight and an okay (scientists are unsure of the extent) sense of taste.
Reproduction
Dolphins are usually docile creatures, but male dolphins have been known to form gangs with other males over control of females. Some males have constrained the movement of females until the female was ready to mate. The female and male have sexual organs in a slit on their underside, so intercourse is belly to belly. The gestation period of the female is around 12 months. Once the baby is born, it will stay with the mother for many years. Female dolphins tend to have babies once every three to six years, sexually maturing at ages five to thirteen. Males mature from ages nine to fourteen. Calves swim in baby positions where the mom surfaces first, and the baby surfaces slightly behind and after. This style limits the distance between the mother and child by the water.
Social
Dolphins are social creatures. They play with each other, they communicate through clicks and whistles, and they cooperate. Dolphins can remember the call of an old buddy 20 years after departing from each other. Dolphins even grieve their dead. Some adult male dolphins roam alone, but many dolphins group with at least 2-3 other dolphins. Dolphins are also part of fission-fusion groups. This means one main group will have groups within that group that might come together or disassociate often. Dolphins are altruistic as well. They have been known not only to save their injured friends but to save injured humans from drowning. Some bottlenose dolphins have been spotted cooperating with human fishers. They chased fish into their nets and ate the ones that got away.
