Dolphins and Porpoises
Ocean Dolphins
Ocean dolphins are members of the largest Cetacean family, the Dolphinidae. This group can vary greatly in size, appearance, diet, social behavior, and habitat. This large and varied group contains 6 subfamilies and at least 33 individual species.
Ocean dolphins share a few common features across o most of these species. Like all toothed cetaceans, they all have a single blowhole on the top of the head, slightly left to center. Their teeth vary in number, but they are generally cone-shaped and undifferentiated. With the exception of finless dolphins, most have a dorsal fin approximately in the center of the back. Their flukes are always cleaved on the rear margin by a notch.
The length and width of the beak is variable; some have a well-defined beak, while others have no beak at all. They also vary greatly in color and pattern.
Ocean dolphins share a few common features across o most of these species. Like all toothed cetaceans, they all have a single blowhole on the top of the head, slightly left to center. Their teeth vary in number, but they are generally cone-shaped and undifferentiated. With the exception of finless dolphins, most have a dorsal fin approximately in the center of the back. Their flukes are always cleaved on the rear margin by a notch.
The length and width of the beak is variable; some have a well-defined beak, while others have no beak at all. They also vary greatly in color and pattern.
Common Bottlenose Dolphin
Scientific Name: Tursiops truncatus
Appearance: The bottlenose has a wide head and body, a short stubby beak, long flippers, and a moderately tall falcate dorsal fin. With a maximum length of 8 to 12 feet and a weight of 570 pounds, they are one of the largest beaked dolphins. Males tend to be larger than the females. They have large teeth, with 20 to 26 pairs in the lower jaw and 18 to 24 pairs in the lower jaw.
The bottlenose dolphins color palate is mostly consists of shades of gray. They have strong countershading, where they are darker on top and lighter on their underside. They have a darker cape starting from the melon that extends back past the dorsal fin. Their sides are a paler gray and their bellies are off-white. Their flippers and flukes are a darker gray.
Diet: Bottlenose dolphins prey on a variety of organisms depending on their habitat. Coastal dolphins eat fish and various invertebrates. Open ocean dolphins eat fish and squid.
Location: These dolphins live in tropical and temperate waters all over the world. There are populations living in a variety of habitats, including coastal, open ocean, bays, and estuaries.
The bottlenose dolphin is one of the most well-known and recognizable dolphin species in the world. They have been featured in many different tv shows and movies, such as the popular “Flipper” series. They are also a common attraction at many aquariums. There have been reports going back to the early Greeks of these dolphins saving people from drowning or shark attacks.
Appearance: The bottlenose has a wide head and body, a short stubby beak, long flippers, and a moderately tall falcate dorsal fin. With a maximum length of 8 to 12 feet and a weight of 570 pounds, they are one of the largest beaked dolphins. Males tend to be larger than the females. They have large teeth, with 20 to 26 pairs in the lower jaw and 18 to 24 pairs in the lower jaw.
The bottlenose dolphins color palate is mostly consists of shades of gray. They have strong countershading, where they are darker on top and lighter on their underside. They have a darker cape starting from the melon that extends back past the dorsal fin. Their sides are a paler gray and their bellies are off-white. Their flippers and flukes are a darker gray.
Diet: Bottlenose dolphins prey on a variety of organisms depending on their habitat. Coastal dolphins eat fish and various invertebrates. Open ocean dolphins eat fish and squid.
Location: These dolphins live in tropical and temperate waters all over the world. There are populations living in a variety of habitats, including coastal, open ocean, bays, and estuaries.
The bottlenose dolphin is one of the most well-known and recognizable dolphin species in the world. They have been featured in many different tv shows and movies, such as the popular “Flipper” series. They are also a common attraction at many aquariums. There have been reports going back to the early Greeks of these dolphins saving people from drowning or shark attacks.
Short-Beaked Common Dolphin
Scientific Name: Delphinus delphis
Appearance: This dolphin has a slender body, long beak, a moderately tall dorsal fin, and moderately large tapered flippers. They have around 41 to 54 pairs of teeth is both jaws.
Their color pattern is quite complex. Their entire back, from their melon to behind their dorsal fin, is a dark gray. This dark color dips onto the sides into a v-shaped saddle. A large portion of their sides are a medium golden-yellow color. They also have a gray patch the starts on their lower back and sweeps forward into the yellow patch. Their underbelly is white. These dolphins grow to be between 8 to 10 feet in length.
Diet: Common dolphins prefer small schooling fish and squid.
Location: These dolphins live mostly in tropical or temperate waters. They prefer to live along shelf edges and in areas where there is a sharp bottom relief, such as shelf edges and escarpments.
These dolphins are very social and often traval in enormous pods of over a thousand. They are very energetic and often enjoy riding the bow waves of boats.
Appearance: This dolphin has a slender body, long beak, a moderately tall dorsal fin, and moderately large tapered flippers. They have around 41 to 54 pairs of teeth is both jaws.
Their color pattern is quite complex. Their entire back, from their melon to behind their dorsal fin, is a dark gray. This dark color dips onto the sides into a v-shaped saddle. A large portion of their sides are a medium golden-yellow color. They also have a gray patch the starts on their lower back and sweeps forward into the yellow patch. Their underbelly is white. These dolphins grow to be between 8 to 10 feet in length.
Diet: Common dolphins prefer small schooling fish and squid.
Location: These dolphins live mostly in tropical or temperate waters. They prefer to live along shelf edges and in areas where there is a sharp bottom relief, such as shelf edges and escarpments.
These dolphins are very social and often traval in enormous pods of over a thousand. They are very energetic and often enjoy riding the bow waves of boats.
Orca (Killer Whale)
Scientific Name: Orcinus orca
Appearance: With it’s robust body, conical head, and defined beak, the orca is the largest member of the delphinid family. They can grow to be 30 feet in length and weigh around 12,000 pounds. Their dorsal fin is large and varies in shape. It is more prominent in males, whose fins can grow up to six feet high. Their flippers are more broad and rounded than most other delphinids.
They have a highly contrasting black and white color scheme. They are mostly black with smaller areas of white. Their underbellies are white from their lower jaw all the way to their flukes. Just before their tails, a white patch comes up onto their sides. They also have distinctive white ovals just above their eyes. A gray to white saddle sits just behind the dorsal fin. The size, color, and shape of this saddle varies greatly from individual to individual.
Diet: Depending on their habitat and preferences, these animals can have a varied diet, including small fish, squid, baleen whales, sea turtles, sharks, seals, penguins, rays, and even the occasional deer, if they catch one swimming across channels. Pods tend to specialize in a few types of prey and often develop special hunting techniques and habits.
Location: The orca is known to be the most widespread cetaceans in the world. They inhabit all oceans, but are most numerous in the Arctic, Antarctic, and areas with nutrient-rich cold water upwellings. They can be found in coastal and open waters, but prefer to live on the continental shelf where the water is less than 650 feet (200 meters) deep.
Thanks to exposure in tv series, movies, and oceanariums, the orca has become one of the most well-known cetaceans in the world.
The name “killer whale” came from whalers, who witnessed these animals hunting and killing larger whales. They are also appropriately called “the Wolves of the Sea”, these predators live and hunt in large pods. They are also called ballena asesina (assassin whale) in Spanish, due to their fierce reputation. Despite their fearsome reputation as a apex predator, they are not known to hunt or attack humans in the wild.
Appearance: With it’s robust body, conical head, and defined beak, the orca is the largest member of the delphinid family. They can grow to be 30 feet in length and weigh around 12,000 pounds. Their dorsal fin is large and varies in shape. It is more prominent in males, whose fins can grow up to six feet high. Their flippers are more broad and rounded than most other delphinids.
They have a highly contrasting black and white color scheme. They are mostly black with smaller areas of white. Their underbellies are white from their lower jaw all the way to their flukes. Just before their tails, a white patch comes up onto their sides. They also have distinctive white ovals just above their eyes. A gray to white saddle sits just behind the dorsal fin. The size, color, and shape of this saddle varies greatly from individual to individual.
Diet: Depending on their habitat and preferences, these animals can have a varied diet, including small fish, squid, baleen whales, sea turtles, sharks, seals, penguins, rays, and even the occasional deer, if they catch one swimming across channels. Pods tend to specialize in a few types of prey and often develop special hunting techniques and habits.
Location: The orca is known to be the most widespread cetaceans in the world. They inhabit all oceans, but are most numerous in the Arctic, Antarctic, and areas with nutrient-rich cold water upwellings. They can be found in coastal and open waters, but prefer to live on the continental shelf where the water is less than 650 feet (200 meters) deep.
Thanks to exposure in tv series, movies, and oceanariums, the orca has become one of the most well-known cetaceans in the world.
The name “killer whale” came from whalers, who witnessed these animals hunting and killing larger whales. They are also appropriately called “the Wolves of the Sea”, these predators live and hunt in large pods. They are also called ballena asesina (assassin whale) in Spanish, due to their fierce reputation. Despite their fearsome reputation as a apex predator, they are not known to hunt or attack humans in the wild.
Porpoises
The word “porpoise” comes from the Latin words porcus, meaning “pig”, and piscus, meaning “fish”. While the term porpoise is often used colloquially to refer to various smaller cetaceans, true porpoises are a different family altogether. Porpoises make up the family Phocoenidae. They are generally very small with no prominent beak and relatively small flippers. Most of them live in shallow water near the shore. It is also the smallest cetacean family, with only 6 spices in total.
Harbor Porpoise
Scientific Name: Phocoena phocoena
Appearance: The body of this animal is rotund and stocky with a very short beak. It’s dorsal fin is triangular and sits mid-back. The harbor porpoises back is a dark gray or brown. It shades to a lighter patch on its sides and its belly is white. Its flippers are dark in color. There is also a dark stripe extending from its mouth to its flippers. It has a maximum length of around 6 feet, though most do not exceed 5 feet.
Diet: Harbor porpoises mostly eat small schooling fish, such as herring, capelin, sprat, and silver hake. They may also eat squid. Claves often eat small crustaceans during their early weaning phases.
Location: These porpoises have a preference for coastal waters and are often found in fjords, bays, estuaries, and harbors, as their name implies. They are only found in northern temperate and subarctic waters. In the Gulf of Maine and Bay of Fundy, calves are often born in May.
These porpoises are very reclusive and shy. They are not as inclined to investigate boats or ride bow waves as many dolphins and porpoises are. Due to their preference for living closer to shore, it is still one of the most studied porpoises.
Appearance: The body of this animal is rotund and stocky with a very short beak. It’s dorsal fin is triangular and sits mid-back. The harbor porpoises back is a dark gray or brown. It shades to a lighter patch on its sides and its belly is white. Its flippers are dark in color. There is also a dark stripe extending from its mouth to its flippers. It has a maximum length of around 6 feet, though most do not exceed 5 feet.
Diet: Harbor porpoises mostly eat small schooling fish, such as herring, capelin, sprat, and silver hake. They may also eat squid. Claves often eat small crustaceans during their early weaning phases.
Location: These porpoises have a preference for coastal waters and are often found in fjords, bays, estuaries, and harbors, as their name implies. They are only found in northern temperate and subarctic waters. In the Gulf of Maine and Bay of Fundy, calves are often born in May.
These porpoises are very reclusive and shy. They are not as inclined to investigate boats or ride bow waves as many dolphins and porpoises are. Due to their preference for living closer to shore, it is still one of the most studied porpoises.
ACS. (2014). Harbor Porpoise. American Cetacean Society. Retrieved from: http://acsonline.org/fact-sheets/harbor-porpoise/
MarineBio. (2014). Common Bottlenose Dolphin. Retrieved from: http://marinebio.org/species.asp?id=33
MarineBio. (2014). Common Dolphin. Retrieved from: http://marinebio.org/species.asp?id=32
MarineBio. (2014). Orcas (Killer Whales). Retrieved from: http://marinebio.org/species.asp?id=84
Reeves, R. R., Stewart, B. S., Clapham, P. J., Powell, J. A. (2002). Guide to Marine Mammals of the World. New York, New York: National Audubon Society.
MarineBio. (2014). Common Bottlenose Dolphin. Retrieved from: http://marinebio.org/species.asp?id=33
MarineBio. (2014). Common Dolphin. Retrieved from: http://marinebio.org/species.asp?id=32
MarineBio. (2014). Orcas (Killer Whales). Retrieved from: http://marinebio.org/species.asp?id=84
Reeves, R. R., Stewart, B. S., Clapham, P. J., Powell, J. A. (2002). Guide to Marine Mammals of the World. New York, New York: National Audubon Society.
Updated: December 3, 2014