Dolphins and Porpoises
There are about 80 species of whales, dolphins and porpoises with 10 of those in the waters off Oregon's coast. These include the mighty gray whale, the awe-inspiring killer whale, and the charming and intelligent bottlenose dolphin.
Let's see how many you know.
The bottlenose dolphin is the most common of the oceanic dolphins and can be found in all tropical and temperate oceans. Flipper was a bottlenose dolphin. The U.S. Navy also uses bottlenose dolphins to find mines and booby traps underwater.
Behavior: Bottlenose dolphins squeak, squawk and use body language—leaping as high as 20 feet in the air, snapping their jaws, slapping their tails on the surface of the water, blowing bubbles and even butting heads. Each dolphin has a special whistle that it creates soon after it is born. This whistle is used for identification, just like a human’s name. They typically live in pods of 10 to 30, but group size varies up to more than 1,000.
Body: They are gray with light gray to white on the undersides. In size they range from six to 13 feet in length and can weigh up to 650 pounds.
Diet: They mainly eat forage fish and often work as a team to harvest fish schools.
Lifespan: 45 to 50 years.
Habitat: They are found all over in the world in warm water areas.
Ecosystem role: They eat other animals – mainly fish and squid – and are themselves a source of food for some sharks and other creatures.
Photo Credit: Allison Henry, NOAA
Pacific White-Sided Dolphin
They prefer deep, off-shore waters, so sightings are usually limited to recreational and commercial fishers. They travel north to Oregon and Washington in the summer.
Behavior: They can be seen travelling in schools of thousands, but group sizes are usually between 10 and 100 animals. These extremely playful dolphins are often seen “bow riding” (swimming near the front part of a ship) and jumping, somersaulting, or even spinning in the air.
Body: Up to 8 feet in length. They have a small and unnoticeable beak and a large hooked dorsal fin. They are dark gray or black on their back, sides and belly but have a striking large gray or off-white patch on both sides.
Diet: They mainly eat hake, anchovies, squid, herring, salmon and cod.
Lifespan: 40 years
Habitat: Pacific white-sided dolphins are found in cold, temperate waters of the North Pacific Ocean from North America to Asia.
Ecosystem role: Pacific white-sided dolphins have a vital ecosystem role as consumers of fish. Seabirds often follow them and consume fish the dolphins do not eat. They are hosts for internal and external parasites.
Photo Credit: NMFS Southwest Fisheries Science Center (NOAA)
Dall’s are the fastest of all small cetaceans and can swim at up to 35 miles per hour, almost as fast as a killer whale. They often ride on the bow wave of boats, but lose interest if the boat isn’t going fast enough. They prefer deep water, so they are not often seen close to land.
Each year about 15,000 Dall’s porpoise are killed by Japanese fishers, making it the largest direct hunt of any cetacean species in the world.
Behavior: Usually found in groups averaging between two and 12 individuals.
Body: A black body with a conspicuous white lateral patch on the left, right, and underside. They are often mistaken for baby killer whales, but unlike killer whales, their dorsal fins are triangle-shaped and they do not have eye patches or saddle patches. About seven feet long and weighing around 400 pounds.
Diet: They can dive up to 1,640 feet to feed on small schooling fish (e.g., anchovies, herring, and hake), mid- and deep-water fish (e.g., myctophids and smelts), cephalopods (e.g., squid and octopus), and occasionally crustaceans (e.g., crabs and shrimp).
Lifespan: 15 to 20 years.
Habitat: Dall's porpoises are common in the North Pacific Ocean and can be found off the U.S. West Coast from California to the Bering Sea in Alaska.
Ecosystem role: They are important predators of fish and cephalopods in the ecosystems in which they live.
Photo Credit: The American Cetacean Society
They usually stay near the surface, coming up about every 25 seconds to breathe with a distinctive puffing noise that sounds like a sneeze.
Behavior: You won’t see them riding the bow waves of boats like a bottlenose. They are also not as social, usually seen alone or in small groups of two or three, rarely more than five individuals.
Body: They are dark gray to black with light gray undersides. They have a blunt, rounded head and small black mouth with inward-curving lips. Five feet and weighing up to 165 pounds.
Diet: Harbor porpoises eat small forage fish, like sardines and herring.
Lifespan: They rarely survive beyond 8 to 12 years, but can live to 20 years.
Habitat: Coastal areas and are most commonly found in bays, estuaries, harbors, and fjords. Most coastal areas in the Northern Hemisphere.
Ecosystem role: They are food for great white sharks and killer whales.
Photo Credit: AVampireTear
Seeing killer whales off the Oregon coast is a rare treat, but whale watchers can usually count on a pod of orca’s patrolling the coast in mid-April – just in time to intercept baby gray whales.
Behavior: Smart and social, orcas make a wide variety of communicative sounds, and each pod has distinctive noises that its members will recognize even at a distance. Orcas hunt in deadly pods, family groups of up to 40 individuals.
Body: Killer whales are black and white, with a gray patch called a "saddle" or a "cape" on the back, just behind the dorsal fin. The largest recorded male killer whale was 32 ft. in length and weighed 22,000 lbs. The largest recorded female was 28 ft. and weighed 16,500 lbs.
Diet: They're at the top of the food chain and have very diverse diets, feasting on fish, penguins, and marine mammals such as seals, sea lions, and even whales.
Lifespan: 50 to 80 years.
Habitat: Found in every ocean in the world, they are the most widely distributed of all cetaceans (whales and dolphins).
Ecosystem role: Killer whales are top predators in most marine ecosystems and impact the populations of common prey, such as seals and sea lions in breeding areas. Killer whales are host to some endoparasites and ectoparasites.
Photo Credit: Robert Pittman - NOAA
The differences between dolphins and porpoises are easy to see if you know what you're looking for.
Check out this diagram.
Can you see the difference? Can you find the porpoises?
Which animals are endangered? How can we help to preserve this species?
What new fact were you surprised by? Why?
Which animals have you seen in person before? Did their behavior match what is written here?
Which animals interests you most? Why?
Choose an animal from this list to research more. How do they make their homes? Do they mate for life? Why are they endangered? etc.
Choose two (or three!) animals from this list and combine them. Create a drawing of your new animal. Give your new species a name. Where does it live? What does it eat? What are its habits?
Pick an endangered animal and search for organizations that support them. Why is it so important that this species be preserved? How could you get involved and help out?
Trick question! There was only one. #10.
Sources: The Oregon Department of Fish and Wildlife, Alaska Fisheries Science Center, Center for Biological Diversity, The National Wildlife Federation, The Marine Mammal Center, National Oceanic and Atmospheric Administration