Sperm whale

Physeter macrocephalus

Sperm whales are around 50 feet in length and weigh around 62 tons. Sperm whales are dark grey to black in color with a distinctive square head, small dorsal fin, and wrinkly skin. They also are well known for their narrow lower jaw carrying around 25 teeth; the upper jaw has no teeth. Sperm whales feed mainly in the depths of the ocean on giant squid, smaller squid, octopus, fish, or even crustaceans using a extremely deafeningly high pitched echolocation that can stun its prey. Sperm whales can be found in pods up to 15 but male sperm whales tend to swim alone. Sperm whales also tend to show their tails while diving and can float at the surface nose up.

Click here to check out an amazing video of the research crew onboard the Nautilus of their ROV (Remotely Operated Underwater Vehicle) encounters a curious sperm whale. 



Common bottlenose dolphin

Tursiops truncatus

Bottlenose dolphins inhabit coastal and can be rarely seen in the offshore waters of Maine. An average bottlenose dolphin is around 12 feet long and about 1,500 pounds. Calves (or baby) Bottlenose dolphins are around 5 feet in length. They are grey in coloring, can range from dark grey (almost black) to very light grey or white. Bottlenose dolphins feed on small fish, squid, crabs, shrimp, and krill. Bottlenose Dolphins use high frequency echolocation to “see” underwater by sending out a high pitched sound that bounces off fish and tells the dolphin where that fish is. They use this to hunt for food as well as see predators. Commonly found swimming in pods (groups) of 5 to 100 dolphins, these pods are part of feeding groups and families.

Click here to find out more about these animals on National Geographic Kids.



Atlantic white-sided dolphin

Lagenorhynchus acutus

Atlantic white-sided dolphins are about 9 feet long and around 400 pounds. Atlantic white-sided dolphins are dark grey in color on the top of their body and have a distinctive yellow/tan streak on the side of their bodies. They also have a longer gray streak going from face to tail and a white underside. Atlantic white-sided dolphins feed on schooling fish and small crustaceans (such as crabs and shrimp). They are known to work in groups to herd fish into a central location for group feeding. Atlantic white-sided dolphins are social animals that can be found in small or large pods. They are also commonly found around larger marine mammals.



Orca whale

Orcinus orca

Also called killer whales, orcas are a rare or unusual animal to see around Maine. Orcas are one of the larger of the toothed whales at an average of 30 feet long (with males being larger than females) and around 9 tons! Orca whales are black with white bellies and white “saddles” behind their dorsal fins (the fin on top of their body). These white patches around their bodies can change depending on location and family. They also have a distinctively tall dorsal fin. Orca whales are highly skilled hunters and can commonly feed on a wide range of animals including: fish, squid, and smaller marine mammals such as seals. Orcas tend to be social animals and swim in pods of 20 or more, while relying on echolocation for hunting and communication.

Fun Fact: There is one orca whale who is commonly seen in the Bay of Fundy named Old Tom. Old Tom is a lone orca who has made small groups of Atlantic white-sided dolphins his pod. Researchers are unsure of how Old Tom lost the rest of his pod but he can be seen feeding and playing happily alone. Click here for an article about Old Tom.

Click here for some lookout locations where you can see orcas through a ongoing live cam by Orca Lab!



Credit: Natural England/Rebecca Walker

White-beaked dolphin

Lagenorhynchus albirostris

White-beaked dolphins are about 8 feet in length and around 780 pounds. They are mostly dark gray or black and back with light gray or white patches on their sides, back, and underside. Their white beak is short and small, mostly white in color at the tip of their mouth. White-beaked dolphins work together in pods to hunt their food, eating schooling fish, crustaceans (crabs or shrimp), and squid. Most of their food is found closer to the surface of the water or in shadow places since white-beaked dolphins do not usually swim deeper than 3,000 feet. These dolphins are highly social animals and are usually found in large pods but also with other larger marine mammals.

Fun Fact: A study found that several white-beaked dolphins in Netherlands had up to 25 different animals as part of their diet.



Harbor porpoise

Phocoena phocoena

Harbor porpoises are notoriously shy animals, often found in shallow waters such as estuaries or, as their name implies, harbors. They measure 4.9 to 6.6 feet, with the females being slightly larger than the males. Their diet mainly consists of herring, cod, sardines, and mackerel. They are usually seen alone, in pairs, or in small groups. Both adults and calves are gray with black lips. They have an average lifespan of 24 years. The harbor porpoise is listed under “least concern” by the IUCN conservation status. It should be noted that they are susceptible to being entangled in fishing nets. They have an average lifespan of 24 years.

Fun fact: They surface to breathe about every 25 seconds. The sound of their exhalation has been compared to a “little sneeze.”

Click here to access their range maps and videos of their behavior.  



Credit: Charlie Jackson

Striped dolphin

Stenella coeruleoalba

Striped dolphins are sociable, often found traveling in large groups. Their playful, curious nature is exemplified by their acrobatic behaviors; they are known for leaping and can jump up to 9 feet. Striped dolphins can be identified by their greyish-blue color, dark flippers, and dark stripe across their bodies. They reach 8-8.5 feet in length with the males being larger than females. Their diet consists of fish, squid, octopus, krill, and other crustaceans. They are most often found near the surface in deeper offshore waters. Their average lifespan is 60 years.

Fun Fact: Striped dolphins exhibit a unique behavior called “roto-tailing,” a jumping-rotation.

Click here to watch them swim! 



Beluga whale

Delphinapterus leucas

Beluga whales are one of the smallest whale species, commonly found in the Arctic and northern waters, although they do occasionally migrate into the Gulf of Maine. Males are larger than females, measuring between 13 to 20 feet in length. The beluga’s diet consists of many different species, including cod, salmon, crab, and herring. They are also diverse in terms of habitat; belugas can be found in deep water, estuaries, or rivers. Beluga calves are born gray, their color lightening with age. Adults are completely white in color. Their lifespan is estimated at between 35 to 50 years. Belugas are listed by the IUCN as near threatened.

Fun Facts: Belugas have the unique ability to turn their head in any direction.

Click here to watch belugas migrate to the Arctic.



Long-finned pilot whale

Globicephala melas

Long-finned pilot whales are a social species, usually found in large groups. They travel in groups of hundreds, but within the large group they separate into smaller groups of 10-20. Males are larger than females in size, measuring to 19-25 feet. They feed on a variety of cephalopods, crustaceans, and fish. They are most often found in deeper offshore habitats. Their average lifespan reaches about 50 years. Their conservation status is “data deficient.”

Fun Fact: Their pods are “maternally based,” usually consisting of more females than males.

Click here to view a Spanish illustration of them from the International Whaling Commission. 



Credit: Roland Edler

True’s beaked whale

Mesoplodon mirus

True’s beaked whale, while elusive, is usually found alone or in small groups. They are deep divers, an adaptation that allows them to feet on cephalopods such as squid. They also consume small species of fish. Females are slightly larger than the males, with an average length of 15.5 to 17.5 feet. As previously mentioned, these whales are elusive so little data is collected on their lifespan or conservation status. We do know their population is threatened by noise pollution in the ocean.

Fun Fact: The True’s beaked whale has a single pair of teeth on its bottom jaw.

Click here to read about how NOAA tracks these elusive whales.