I went through Massachusetts to get on a whale-watching trip recently. I was surprised at how many different environments I drove through. The habitats ranged from scrubland, grassland, and forests. With the various mammals in the state, these habitats are essential for the mammals that live there.
Massachusetts has 83 mammal species, including bears, rodents, whales, porpoises, and dolphins.
According to the Massachusetts government website, there are currently over 80 species of mammals living in Massachusetts. I have excluded any extirpated or accidental sightings from this list.
|Fox and coyote||2|
|Rabbits and hare||5|
|Shrews and moles||8|
The American beaver is a nocturnal semiaquatic mammal and the largest rodent in North America. They live in colonies and have orange teeth because they contain a lot of iron. This makes their teeth stronger than regular teeth. They are well known for building dams, canals, and lodges.
Their color is dark brown, measuring from 74 to 90 cm and weighing 11 to 32 kg. The beaver is an herbivore that eats bark, cambium, roots, buds, and water plants. The North American beaver lives in forests (near water bodies) in northern North America, with a lifespan between 10 to 15 years. In Massachusetts, they can be found in northeastern, central, and Western Massachusetts and occasionally in the state’s southeast.
American Black Bear
The American black bear is a midsize mammal from North America. Their color is not always black but can be brown, tan, and even blonde. They measure from 130 to 190 cm and weigh 200 to 300 kg.
The black bear is an omnivore and has an extensive diet. This consists primarily of fish, mammals, insects, grasses, roots, and berries. This bear species is broadly distributed in forest habitats, with an average lifespan of 20 years.
The black bear can be found in most forests in the state, although not common in the Southeast of Barnstable, Plymouth, or Bristol.
American Water Shrew
The American water shrew is a solitary and semiaquatic species of the shrew—their color changes throughout the year, from light brown in the summer to black in the winter. The water shrew measures 13 to 17 cm and weighs 8 to 18 g.
This species of water shrew is an omnivore eating aquatic insects, small fish, plants, and snails. They live in streams and ponds, with a lifespan of about 18 months.
In Massachusetts, they are listed as a special concern species and can be found in west Massachusetts in Berkshire, Franklin, Hampden, and Hampshire. They can also be located in the center of the county in Worcester.
Atlantic White-sided Dolphin
The Atlantic white-sided dolphin grows from 6.2-9.2ft (1.9-2.8m) with a weight between 360-520 lb. They are similar in color to the common dolphin, with gray, white, and yellow along the flanks and a white underside.
The Atlantic white-sided dolphin has a dark-gray stripe from the eye to the flipper and a dark dorsal fin and flippers. They give birth to a single calf after a gestation period of 11 months.
The white-sided dolphin can be seen off the coast of Barnstable and Essex and the Island of Nantucket.
The bearded seal, also known as the square flipper seal, is a medium-sized species native to the Arctic Ocean. They are found in a wide range, from Bristol Bay on the Alaskan coast to the Sea of Okhotsk on the Russian Coast. They can also be found in Canada, Norway, and Japan. These earless seals are grayish-brown and darker on the back. The bearded seal was seen in Essex County in Massachusetts in 2002, but it will occasionally enter the state’s waters.
Females of this species are larger than males. On average, bearded seals measure about 2.1 to 2.7 meters in body length, and their mass spans between 200 to 430 kilograms. They are a significant food source for polar bears. These seals feed primarily on small marine species, including clams, squids, and fish.
The beluga is easy to spot due to its almost pure white, yellowish or pale gray color. They have no mottling on either side. They grow from 9.8-18 ft (3-5.5m) with a weight of 1,100-3,500 lbs. They have a gestation period of 12-14.5 months and give birth to one calf.
They eat a wide variety of fish, squid, octopuses, and mollusks. They change color as they age, with a pale gray at birth, dark-brown to brownish-gray, and completely white at ten.
They can be seen close to shore and, when stranded, can generally survive until the tide comes back in. They have been sighted in waters off Barnstable, Bristol, Dukes, and Essex counties.
Big Brown Bat
The big brown bat is an insectivore that eats mostly beetles and consumes other flying insects like moths, flies, and wasps. They live in all habitats, ranging from 18 to 20 years. This animal carries a lot of diseases, including rabies and parasites such as tapeworms and fleas.
The big brown bat is a small, nocturnal flying mammal. They live in colonies and use echolocation to locate objects while flying at night. The color varies from brown to black. They measure 11 to 13 cm, with a wingspan from 32 to 40 cm, weighing 15 to 26 g.
The bat lives in North America, Central America, the Caribbean, and the northern portion of South America. In Massachusetts, they can be found all over the state.
The black-tailed jackrabbit is also known as the American desert hare and is common in the United States and Mexico’s western regions. They live at high elevations, up to 3000 meters above sea level. They generally measure around 61 cm in length and weigh about 1.4 to 2.7 kilograms.
Black-tailed jackrabbits are characterized by big ears that are black-tipped on the outer surfaces. Their fur is usually grayish-brown with white underparts. Females of this species tend to be larger than males. The diet of the jackrabbit is mainly made of shrubs, small trees, and grasses.
There are no populations of black-tailed jackrabbits on the mainland of Massachusetts. There was a population on Nantucket, but it is unknown if there are any left.
Blainville’s Beaked Whale
A member of the beaked whale family, Blainville’s beaked whale, is medium-sized. They measure between 13.7-15.4 ft (4.2-4.7m) with a weight between 0.8-1.1 tons. They feed on deep-water squid and some fish. They are dark brown or blue-gray with a lighter underside.
This beaked whale has a flat forehead, and the head at the blowhole is indented. They have a reasonably long neck with an arched lower jaw. Blainville’s beaked whale is also known as the dense-beaked whale due to Hendi de Blainville stating that a piece of bone he had was the densest bone structure he had ever seen.
They are never seen close to shore in Massachusetts but can be seen in coastal waters.
The blue whale is the largest living animal on Earth, not just now but ever. This whale species reaches sizes between 69-95 ft (21-29m), although they are slightly smaller in the Northern Hemisphere. Females are larger than males and can reach incredible weights of 90-150 tons.
The diet of a blue whale consists mainly of krill, with some crabs and squid. They are easy to spot because of their vast size and flattened, broad, u-shaped heads. Even though they are so large, they have a tiny dorsal fin set far back.
The blue whale is an endangered species in Massachusetts. They have been seen on the coasts of Barnstable, Essex, Suffolk, and Norfolk counties but are generally seen offshore.
The bobcat is a nocturnal and elusive midsize wildcat from North America (related to the lynx). They look like big domestic cats with bobbed tails. Their color can range from grayish brown to red, with a white underbody. They measure from 47 to 125 cm and weigh 8 to 9 kg.
The bobcat is a carnivore and eats raccoons, squirrels, rodents, rabbits, birds, reptiles, skunks, and sometimes even deer. They have extraordinary night vision and can live in all types of habitats across the central section of North America. Their lifespan ranges from 10 to 12 years.
Although classed as the least concern, bobcats are hard to spot in Massachusetts. Most sightings occur in central and western counties of the state but occasionally in Bristol, Norfolk, and Plymouth.
The common bottlenose dolphin grows from 6.2-13.1 ft (1.9-4m). Their diet consists mainly of squid and small fish. They have a single calf with a gestation period of 12 months.
Bottlenose dolphins are gray to black, with a lighter underside and a dorsal cape. They have a short beak with a mouthline that makes them look like they are smiling. The common bottlenose dolphin is one you will most likely have seen on television or in films.
They have been seen off the coast of Barnstable, Essex, Plymouth counties, and Dukes and Nantucket’s islands.
The brown rat is a rodent that lives all over the world. Their color is brown with a lighter color on the underbody. They measure from 15 to 28 cm and weigh 140 to 500 g.
The brown rat is an omnivore, eating seeds, nuts, grains, fruits, eggs, birds, mice, small rabbits, fish, and insects. They live in forests, areas with bushes, and urban and suburban areas, with a lifespan of two years.
They can be found in every county in Massachusetts.
The Cinereus shrew is also known as the masked or common shrew. They are small, nocturnal, and solitary animals. Their color is grayish-brown, with a lighter grayish hue in the underbody. They measure about 9 cm, weigh just 5g, and have a lifespan of just 14 months.
The cinereus shrew is a carnivore and eats insect larvae, ants, grasshoppers, crickets, spiders, worms, snails, small rodents, and salamanders. They live in North America’s grasslands, forests, riverbanks, lakeshores, and tundra. Their lifespan is just 14 months.
The cinereus shrew is the least concerned and can be found all over Massachusetts.
The muskrat is the only species of the genus Ondatra. They are medium-sized semiaquatic rodents found in wetlands in many climates and habitats. Their average measurements are about 40-70 cm in length and they weigh around 0.6-2kg. Although commonly referred to as a rat, muskrats are a different kind of rodent.
The fur of the muskrat is thick and short of a dark-brown color. Their tails are covered with scales (not hair), which helps them swim rapidly and efficiently. Muskrats spend most of their time in the water and can swim underwater for up to 17 minutes. This species usually lives in a group made up of a male and female and their offspring. Muskrats make nests to protect themselves from the cold and predators, usually in caves with an underwater entrance.
In Massachusetts, the muskrat can be found everywhere except on the island of Nantucket County.
The coyote is a midsize wild canine with a domestic dog’s look, although thinner and smaller than the gray wolf. Their color is grayish-brown with a white underbody. They measure about 1.5 m (including the tail) and weigh 6.8 to 21 kg.
This highly adaptable omnivore has an extremely varied diet: cactus fruits, flowers, insects, rodents, rabbits, birds, and reptiles. They can be found in any habitat across North and Central America. Their lifespan ranges from 10 to 14 years in the wild and up to 21 years in captivity.
Coyotes can be seen in every county in the state except the island of Marthas Vineyard and Nantucket.
Cuvier’s Beaked Whale
Cuvier’s beaked whales grow between 18-23 ft (5.5-7m) with a weight between 2.2 – 3.9 tons. They feed on squid, fish, and crustaceans. They generally have scarring and shark bits on the gray or reddish-brown body. They have a sloping forehead and a slightly concave head.
Cuvier’s beaked whales are known to breach but generally avoid boats, although they are one of the most-watched beaked whales. Although they may be seen alone, groups of seven may travel together. Groups of 25 have been seen together, although this is rare.
Although they have been found stranded in Massachusetts, they are rarely seen near shore.
Dwarf Sperm Whale
The dwarf sperm whale measures 6.9-8.9 ft (2.1-2.7m) with a weight between 300-600 lb. They look similar to the pygmy sperm whale but have a squarish head, flatter back, and a more prominent, pointed, erect dorsal fin.
The dwarf sperm whale has been said to resemble an upside-down surfboard when seen in the water. Dwarf sperm whales are usually seen lying motionless at the water’s surface. They eat squid and octopus, along with fish and crustaceans.
They are rarely seen in Massachusetts but occasionally off the coast of Barnstable, Essex, and Nantucket counties.
The Eastern chipmunk is a solitary animal. Their color is reddish-brown, with two white stripes surrounded by black stripes on the side of their back and head, with a fifth black stripe running across the center of their back. The chipmunk’s underbody has a lighter brown color. They measure about 30 cm (including the tail) and weigh 66 to 150 g.
The Eastern chipmunk is an omnivore that eats acorns, insects, eggs, mushrooms, snails, nuts, fruits, seeds, berries, and corn. They like to live in rocky areas, logs, and bushes in deciduous forests and urban parks. They live in the eastern United States and Southeast Canada, with a lifespan of three years.
The Eastern chipmunk is not seen in Nantucket County but can be found in all mainland counties.
The Eastern cottontail is a solitary, primarily nocturnal rabbit that lives in the southeast of the United States and Central and South America. Their color varies from reddish-brown to grayish-brown, with a white underbody. They measure about 37 cm and weigh about 1.2 kg.
The Eastern cottontail is a herbivore that eats various grasses, branches, bark, clover, fruits, and vegetables. Their habitat is mainly grasslands. Their lifespan is three years in the wild and eight years in captivity.
In Massachusetts, the Eastern cottontail can be found all over the state.
Eastern Gray Squirrel
The Eastern gray squirrel is a diurnal and solitary animal. The color varies from gray to grayish red, and the underbody is white. They measure from 23 to 30 cm (including the tail) and weigh 400 to 600 g.
The Eastern gray squirrel is an omnivore and eats nuts, acorns, insects, berries, bird eggs, and seeds. They have an expected lifespan of six years.
The Eastern gray squirrel is an adaptable animal that lives in the trees on the Eastern side of North America. They can be found in all counties in Massachusetts and have been introduced into Nantucket County recently.
The Eastern mole is a solitary, midsize mammal from the eastern United States. Their color is dark gray. They measure from 14 to 18 cm and weigh 40 to 50 g. This carnivore eats worms, insects, larvae, mice, bugs, and small birds.
Eastern moles live in grasslands and thin forests, with an expected lifespan of six years. The Eastern mole digs tunnels in search of food. Although they control the number of insects in a given location (preventing pests), the damage they cause in gardens makes people despise them.
Eastern Red Bat
The Eastern red bat is found across North America and is a microbat species. They measure 109 mm (4.3 in) with a weight of just 7 to 13. They have pointed, long wings, short ears, and long tails.
Eastern red bats are very maneuverable and can fly quickly. They do not hibernate, chasing to stay in the same regions all year. They are prioritized as the least concern by the IUCN. They can be found statewide in Massachusetts.
Eastern Small-footed Bat
The Eastern small-footed bat is a nocturnal mammal found in the eastern United States and southeastern Canada. Their face, ears, and wings are black, and the rest of the body is grayish brown. They measure from 6.5 to 9.5 cm, with a wingspan ranging from 21 to 25 cm, and weigh from 4 to 8 g.
The Eastern small-footed bat is an insectivore eating beetles, moths, mosquitoes, and flies. They live in forests with caves and rock formations adequate for roosting. Their lifespan is 6 to 12 years in the wild, hibernating in winter.
The Eastern small-footed bat is an endangered mammal on the IUCN red list but can be found in Berkshire and Hampden counties.
The ermine is a solitary weasel in the continent’s northern part. Their color is dark brown on the back and white on the underbody during the summer. In winter, their color changes to almost pure white. They measure from 17 to 32 cm and weigh about 260 g.
Ermine is a carnivore that eats mainly rodents but sometimes will eat birds, fish, amphibians, small reptiles, and insects. They live in taigas and tundras, with a lifespan of 4 to 6 years in the wild. They can be found statewide except on the islands.
The European rabbit is a small rabbit measuring 40 cm in length with a 2.6-4.4 lb weight. Their ears are large, measuring between 6.5-7.5 cm in length.
The rabbits are of various colors but generally gray-brown with black, gray, or red hairs on the body. They are born with a white star shape on their foreheads, but this fades by adulthood. They live in warrens with other rabbits, generally up to ten.
There may still be some of these species on Boston Harbor islands.
The fin whale is a giant growing between 59-88 ft (18-27m), although slightly smaller in the Northern Hemisphere. They reach a weight between 34-100 tons. There are several thousand off the West Coast of America.
They have pigmentation on their heads that is different on both sides, rare for a whale. This is said to be to confuse their prey. They are the second-largest living animal on Earth after the blue whale. Populations of the fin whale can be seen almost year-round in the Gulf of California.\
The fin whale is listed on the IUCN red list as endangered but can be seen off Barnstable, Essex, Norfolk, and Suffolk counties.
The fisher is a small, solitary, mainly nocturnal, aggressive, and elusive weasel. They are related to the American marten. Their color varies from dark brown to black, with a lifespan of seven years in the wild and, in rare cases, up to 14 years in captivity. They measure from 75 to 120 cm and weigh 2 to 6 kg.
The fisher is a carnivore that eats mice, snowshoe hares, birds, cats, poultry, shrews, porcupines, and squirrels. Even though they move on the ground most of the time, they are excellent climbers.
They live in forests in the southern part of Canada and the northern and western parts of the United States. In Massachusetts, they can be seen in every mainland county.
The gray fox is a solitary canine in the southern part of the United States, Mexico, Central America, and the northern parts of South America. Their back has a scattered combination of light and dark gray, the sides are reddish-brown, and the underbody is white. They measure from 76 to 112.5 cm and weigh from 3.6 to 7 kg.
The gray fox is an omnivore that eats mice, birds, voles, rabbits, insects, corn, fruits, nuts, and berries. Their lifespan is 16 years in the wild and 20 in captivity.
They live in dense forests, in areas with rocky terrain or thick vegetation on the mainland, except for Suffolk County and the islands.
The gray seal lives in huge groups on all the coasts of the North Atlantic Ocean. Their colors vary from gray to black or dark brown, and typically their skins are spotted. They measure from 1.95 to 2.3 m long and weigh 170 to 310 kg.
The gray seal is a carnivore that eats fish, crabs, lobsters, shrimp, octopuses, squids, and seabirds. Their lifespan is 25 to 35 years.
Gray seals live on rocky coasts, floating ice sheets, sandbanks, and icebergs. They can be found in Barnstable, Dukes, Essex, and Nantucket counties.
The hairy-tailed mole is a midsize mammal found in the eastern United States and southeastern Canada. Their color is dark gray. It measures from 13 to 15 cm and weighs about 51 g. This insectivore eats worms, larvae, slugs, and ants. The hairy-tailed mole lives in deciduous and coniferous forests and open areas. Their lifespan is up to four years.
They can be found in the state’s central, western, and northeastern counties.
The harbor porpoise is a small, shy, elusive marine mammal relative to dolphins. They are dark gray on top and a much whiter gray on the underbody. They measure from 1.4 to 1.9 m and weigh 61 to 76 kg.
The harbor porpoise is a carnivore and mainly eats fish and sometimes octopuses and squids. They like to swim in shallow water bodies and even frequent inland water bodies, like rivers and estuaries. Their average lifespan in the wild is about 20 years.
The harbor porpoise lives in the northern part of the Atlantic and Pacific Oceans (and in both the East and the West coasts of the northern part of North America). They can be seen off Barnstable, Bristol, Dukes, Essex, Nantucket, Norfolk, Plymouth, and Suffolk counties.
The harbor seal is a marine mammal known as the common seal. Their color is brownish gray with light or dark spots, and the color is lighter on the underbody. They measure 1.85 m and weigh from 55 to 168 kg.
This carnivore eats squids, crustaceans, shrimp, crabs, mollusks, and fish. They mainly live in harbors in the northern parts of the world (and on both the East and west coasts of the northern part of North America). They are excellent swimmers and have a lifespan of 20 to 35 years.
They are usually found in rocks, beaches, and glacier ice, rarely moving from too far but rushing to deeper water if there is danger. They can be seen in Barnstable, Bristol, Dukes, Essex, Nantucket, Norfolk, Plymouth, and Suffolk.
The harp seal is part of the earless seal species. They can be found in the Atlantic Ocean and the Arctic Ocean. They have fur of silver-gray with black spots and jet-black eyes. They grow from 1.7 to 2.0m and weigh from 115 to 145 kg. Unlike other seals, the harp seal can dive too deep depths.
They have been spotted at over 500m deep and can hold their breath for up to twenty minutes. Dive depth increases in winter when there is less food at shallow depths.
The harp seal has been seen in Barnstable, Dukes, Essex, Nantucket, Plymouth, and Suffolk counties.
The hoary bat is a vesper bat species found in most areas of North America and much of South America. This species usually ranges between 13 to 14.5 centimeters in length and weighs approximately 26 grams.
The hoary bat is the largest in Canada. They are characterized by dense dark brown coats with white tips, from which the name comes. Females can be up to 40% heavier than males. These bats usually roost solitarily on trees, hidden by foliage. They live in coniferous forests and generally hunt over open areas or lakes. They have a very long migratory pattern.
The hoary bat can be seen statewide throughout Massachusetts.
The hooded seal gets its name from an inflatable bladder on the head of the male. The bladder hangs over the eyes and the lips when deflated. The sac can inflate, which the seal can use when swimming to ward off other species when it feels threatened. The males also have a membrane that comes out of the left nostril and produces sounds that they use to attract a mate, but mainly for acoustic signaling.
The hooded seal is an extremely rare sight in Massachusetts.
The house mouse is a secretive and cautious mouse that is sometimes domesticated. Their color is gray, black, or brown, with a lighter underbody. They measure from 7.5 to 10 cm (including the tail) and weigh 40 to 45 g. The house mouse is an omnivore eating meat, fruits, seeds, and grains. Their lifespan is less than one year in the wild and 2 to 3 years in protected environments.
The house mouse tends to live in places where humans live. The house mouse can be seen everywhere except on Martha’s Vineyard island.
The humpback whale grows between 46-56 ft (14-17m), weighing 28-45 tons. They approach whale-watching boars and are inquisitive. They are very popular with whale watchers due to their breaching, lob tailing, spy hopping, and flipper-slapping. They have a gestation period of 11-12 months and give birth to one calf.
They can be seen in many places, with Hawaii and Alaska as the perfect places to spot them. In Massachusetts, they can be seen off Barnstable, Essex, Nantucket, Norfolk, Plymouth, and Suffolk.
The killer whale is also commonly known as the Orca, a name taken from its binomial name of Orcinus orca. Killer whales are the largest dolphin family members, growing from 6 to 8 meters long and 5.9 tons. Females are smaller than males. They are one of the fastest marine mammals due to their size and incredible strength, reaching speeds up to 56 km/h. They have a black upper side with a white underside.
Orcas can be seen from Barnstable, Dukes, Essex, and Nantucket.
Little Brown Bat
The little brown bat is a small North American bat. Their colors vary from light tan to dark brown, with more golden color on their underbody. It measures 8 to 9.5 cm and weighs from 5.5 to 12.5 g. This insectivore eats mosquitoes, moths, beetles, etc. Their lifespan is from 6 to 7 years.
They live in most of North America. They will find places to roost during the day, such as trees, caves, and rocks. In winter, this bat hibernates in caves. Although they are endangered on the IUCN red list, they live over most of the state.
Long-finned Pilot Whale
The long-finned pilot whale is a large and very social species of dolphin found in the North Atlantic and Antarctic oceans. Their color is typically black but can be dark gray or brown. They have a light gray mark from the eyes to the dorsal fin. The pilot whale measures from 3.7 to 6.7 m and weighs 1,000 to 3,000 kg.
They are carnivores and eat turbot, squid, dogfish, hake, octopus, cod, and shrimp. Their lifespan is up to an impressive 45 years.
The long-finned pilot whale lives in cold, mild water, closer to the North and South Poles. In Massachusetts, they can be seen rarely in Barnstable, Essex, and Nantucket counties.
The long-tailed shrew is a tiny shrew measuring 48 to 79 mm. Their tail takes the total length to 120 mm. They weigh just 3.1 to 8.3 g. Their long tail is used to help them balance when they climb in their rocky habitat. They are gray to black.
They live in mountainous territories, around and under rocks or near streams. The long-tailed shrew is a special concern in Massachusetts and can only be found in Berkshire County.
The long-tailed weasel is a fearless, aggressive hunter. They are also called the bridled weasel or the big stoat. Their color is reddish-brown with a light yellow underbody. However, in cold, northern regions, they are entirely white. It measures 23 to 35 cm and weighs 85 to 267 g.
The weasel can attack animals that are twice their height. They eat primarily mice, voles, rabbits, chipmunks, birds, eggs, and insects. Their lifespan is up to five years.
The long-tailed weasel lives in grasslands and thin forests (sub-tropical areas with mild temperatures) in the southern part of North America, Central America, and the northern part of South America. They can be found all over the state except on the islands of Dukes and Nantucket counties.
Meadow Jumping Mouse
The meadow jumping mouse is a solitary and primarily nocturnal North American rodent. They can jump 8 feet or more when they are disturbed. Their color is light brown, with a thick dark brown stripe on their back and a white underbody. They measure from 18 to 24 cm (including the tail) and weigh 11.5 to 35 g.
This omnivore eats seeds, insects, and fruits primarily. Their lifespan is less than a year in the wild but up to five years in captivity.
The meadow jumping mouse lives mostly in grasslands, thin forests, and humid areas in the northern part of the U.S. They can be found all over Massachusetts.
The meadow vole is a small, primarily nocturnal rodent. They are also called field mice or meadow mice. Their colors vary from yellowish or reddish-brown to dark brown, and the underbody is gray. They measure about 12 cm and weigh about 43g.
This herbivore eats grasses, grains, seeds, bark, roots, and fruits. They are excellent swimmers and very good at digging holes. Their lifespan ranges from 2 to 16 months. Some people consider them a pest because they cause great damage to plants. They also carry similar diseases to other rodents.
They live in dense grasslands and thin forests in the northern part of North America (except for the most intense polar regions). They can be found statewide in Massachusetts.
The moose is a solitary animal with huge antlers and is the largest member of the deer family. Their color ranges from light to dark brown. The moose is massive, measuring from 1.4 to 2.1 m in height and 2.4 to 3.2 m in length. They weigh from 200 to 700 kg and are herbivores. They eat bark, leaves, pine cones, young branches, and fruits.
In Massachusetts, they live in the counties in central and western counties but may also be found in Bristol and Plymouth. Moose live in forests in the northern part of the continent and have a 15 to 25 years lifespan.
New England Cottontail
The New England cottontail is a rabbit found in the eastern part of the United States, from New York to Maine. They are one of the North American mammals. Their color is dark brown with small, scattered black dots and white underbody and tail. It measures 39.8 to 43.9 cm and weighs from 995 to 1,347 g.
This herbivore eats grasses, leaves, wood, seeds, stems, flowers, fruits, bark, and forbs. It lives in young forests. Their lifespan is about three years in the wild. They are considered a vulnerable species, but they are still not endangered.
The New England cottontail is called the gray rabbit, brush rabbit, or Cooney and is usually located in New England, from Maine to southern New York. In Massachusetts, they are found statewide except on the islands. Their current population is estimated to be 85% less than in the 1960s, which made the species “protected” under the Endangered Species Act.
Their weight is between 995 grams and 1347 grams, with a total body length of approximately 398-439 mm. These rabbits live in forests with dense and thick brush, preferably blueberries. They like to live on a higher elevation, creating depressions where they nest.
North American Deer Mouse
The deer mouse is a small and reclusive rodent. Their color (which resembles a deer) varies from gray to brown, and the underbody is white. They measure 8 to 10 cm (without the tail) and weigh about 20 g. This omnivore feeds on various foods, such as seeds, nuts, fruits, and insects.
Their lifespan is eight years in captivity and less than a year in the wild. They can carry viruses and bacteria that cause human diseases, such as Hantavirus Pulmonary Syndrome (HPS).
This deer mouse species lives in many habitats (forests, mountains, deserts, grasslands, tropical regions) throughout most of North America. They can be found in every county in Massachusetts.
North American Porcupine
The North American porcupine is also known as the common porcupine and they are a rodent with black or brown fur with hairless feet to climb trees. They can be easily recognized by quills, solid at the tip and base, and present around all its body except for the stomach. The quills are used as a defense mechanism.
They are a herbivore, and they are often found climbing on trees to eat leaves. Its size makes it the second-largest rodent in North America. The head-to-body length is approximately 60-90 cm without counting the tail, measuring around 14.5 up to 30 cm. Their weight is about 9 kilograms on average.
The porcupine can be found in central, western, and northeastern counties but has also been seen in Barnstable and Plymouth counties.
North American River Otter
The river otter is an intelligent, semiaquatic mammal from northern North America. It has short, very dense fur. Their colors vary from gray to brown, with a lighter underbody. It measures from 66 to 107 cm and weighs 5 to 14 kg. This carnivore eats mainly fish, turtles, frogs, crayfish, and insects.
The otter lives in aquatic habitats in the northern part of North America. Their lifespan is 8 to 9 years in the wild and 15 to 20 years in captivity. The otter can be seen statewide in Massachusetts except in Nantucket or Suffolk counties.
North Atlantic Right Whale
The North Atlantic right whale is between 49 and 52 ft (15-16m), weighing between 34 and 78 tons. Females grow larger than males. They live mainly on krill and copepods. They are slow swimmers but can be acrobatic. Their behavior includes lobtails, flipper-slaps, and frequent breaches.
The North Atlantic right whale is very curious and approaches boats. Their name comes from whalers who thought they were the right whale to catch. They have a single calf after 12-13 months of gestation. They have no dorsal fin, a dark body, and a large head covered in rough skin patches.
The right whale can be seen off the coast in Barnstable, Dukes, and Plymouth counties. The North Atlantic Right whale is listed as endangered in the state.
Northern Bottlenose Whale
The Northern bottlenose whale is a medium-sized whale. They measure from 19-32 ft (5.8-9.8m) with a weight between 6.4-8.3 tons. They feed mainly on squid and shoaling fish. They are dark gray or brown with a cylindrical bottle. They have a forehead that is squared off behind the beak, which is tubelike.
These whales often approach boats and are pretty curious. They have a single calf after a gestation period of 12 months. The Northern bottlenose whale is very rarely seen around Massachusetts.
Northern Flying Squirrel
The Northern flying squirrel is a nocturnal mammal with a furry membrane between its front and hind legs, which they use to glide from tree to tree. Their color varies from gray to dark brown, with white on their underbody. They measure about 16 cm and weigh about 140 g. This omnivore eats nuts, acorns, fruits, buds, fungi, insects, bird eggs, and lichens.
The Northern flying squirrel lives in forests in the northern part of the continent with a lifespan of four years. In Massachusetts, they can be found in central and western counties of the state.
Northern Long-eared Myotis
The Northern long-eared myotis is a bat in North America. It uses echolocation to navigate while flying. Their color varies from yellowish-light brown to black. They measure about 8.6 cm and weigh from 5 to 8 g. This insectivore eats mostly moths, beetles, flies, and leafhoppers. Their lifespan is about 18.5 years.
They live in boreal forests (Taiga) in the eastern, central part of North America. The Northern long-eared myotis is listed as endangered in the state but can be found in every county. They are an endangered species due to a sickness that is killing their species.
Northern Short-tailed Shrew
The Northern short-tailed shrew is a mammal found in northern North America. Their color is dark gray, with a lighter shade of gray on the underbody. They measure from 11 to 14 cm and weigh 15 to 30 g.
This species of shrew is a carnivore, eating insects, salamanders, worms, mice, snails, seeds, voles, and fungi.
They can live in many habitats, including grasslands and deciduous and coniferous forests, with an expected lifespan of 1 to 3 years. The Northern short-tailed shrew can be found in Berkshire County. They are listed as a species of special concern.
Pantropical Spotted Dolphin
The Pantropical spotted dolphin has a slender body with a narrow beak and whitish lips. There is a crease between the beak and the melon and a dark stripe from the brim to the flipper. They grow from 5.2-8.5 ft (1.6-2.6m) with weights of 265 lb. They are heavily spotted on the sides, with a gray cape on the dorsal side and a light underside.
The Pantropical spotted dolphin was one of the species caught most by tuna fishermen in the past. The spotted dolphin can be seen off the coast in Barnstable, Dukes, and Nantucket counties.
Pygmy Sperm Whale
The pygmy sperm whale grows between 8.9-12.5 ft with a weight between 700 -1000 lb. They eat squid and octopus but will also eat crustaceans and fish. They leave behind a squid-ink-like substance in the water when frightened or startled, leaving a cloud in the water.
They look similar to the dwarf sperm whale but have a small, hooked dorsal fin and are more rounded in profile. They have small bodies and are sometimes mistaken for sharks.
Pygmy sperm whales are often stranded in places like Florida. Although rare in Massachusetts, they can be seen off Barnstable, Essex, and Nantucket counties.
The raccoon is a primarily nocturnal midsize mammal from North America. Their color is gray, brown, or black and their white face with a black area around their eyes is very characteristic. They measure from 40 to 70 cm and weigh 5 to 26 kg.
This opportunistic omnivore eats fruits, plants, oak nuts, insects, worms, rodents, frogs, nuts, eggs, and crayfish. The average lifespan of a raccoon is 2 to 3 years.
Raccoons live in forests and suburban and urban areas in North America’s Central and southern parts. The raccoon can be found in all counties in Massachusetts except Nantucket County.
The red fox is a midsize canine in northern North America, Asia, Europe, and North Africa. The color varies from light yellow to red, with dark legs and a white underbody. It measures from 45 to 90 cm and weighs from 2.2 to 14 kg. Their lifespan is from 2 to 5 years.
This omnivore eats grasses, fruits, corn, apples, oak nuts, cherries, berries, mice, birds, rabbits, squirrels, crickets, grasshoppers, beetles, caterpillars, and crayfish.
The red fox lives in forests, grasslands, mountains, deserts, and suburban areas. This fox species can be found in all counties except Martha’s Vineyard and Nantucket County islands.
The red squirrel is a small, solitary, and diurnal animal in North America. Its color is gray, red, or dark brown, with white on its underbody and sometimes black stripes on its sides. They measure from 28 to 35 cm (including the tail) and weigh from 200 to 282 g. This granivore animal eats mostly sunflower seeds and all types of nuts.
This arboreal animal lives in coniferous, deciduous, and mixed forests, with 5 to 10 years of life. The red squirrel can be found in all counties except Dukes and Nantucket.
The ringed seal is also known as the jar seal, nets, or attic and is a species of earless seal usually inhabiting the Arctic and sub-Artic regions. They are relatively small-sized seals, which rarely measure more than 1.5 meters in length.
The average dimensions span between 100 to 175 cm in body length, and their body mass is usually between 32 to 140 kilograms. These seals are characterized by a distinct pattern of dark spots surrounded by light gray rings that give rise to their common name.
Although listed as a Massachusetts mammal, they are extremely rare in the state.
Risso’s dolphin looks completely different from any other species of dolphin. When playing or fighting, they are heavily scarred, either from squid or from each other. They have a bulbous, large head with a beak that is not distinct.
They have a crease on the melon’s front, with the dark dorsal fin, flipper, and flukes. They are in various colors, ranging from light white to dark gray. They are large dolphins growing from 12.5-13.5 ft (3.8-4.1m) and weighing from 660-1,100 lb,
Risso’s dolphins are rare in the state but can be seen off Barnstable, Essex, and Nantucket counties.
The sei whale is a giant, measuring 39-52 ft (12-18m) and weighing between 17-45 tons. The females are larger than the males. There are no commercial whale-watching operations anywhere dedicated to watching this species. They do not gather in the same areas from one season to the next as most whales do, making them elusive.
They have a more varied diet than most other baleen whales, including krill, copepods, crustaceans, and schooling fish. They are primarily dark gray or brown, with a prominent dorsal fin.
The Sei whale is endangered in Massachusetts but can be seen off the coast of Barnstable and Essex counties.
Short-beaked Common Dolphin
The short-beaked common dolphin is also known as the common porpoise. Males are slightly larger than females, with sizes between 5.2-8.9 ft (1.6-2.7m) and a weight of 155-440 lb. They are fast swimmers and can be seen bow-riding alongside ships.
Herds of this species can be seen in sizes ranging from 10 to 10,000. They have a short beak with a dark cape with a ‘v’ shape under the fin. They have a white underside and yellow or tan patches on their sides.
The short-beaked common dolphin can be seen mainly off the coast of Barnstable, Essex, and Nantucket counties.
Short-finned Pilot Whale
The short-finned pilot whale is medium-sized, growing from 12-23 ft (3.6-7.2m) and weighing between 1.1-3.9 tons. They are dark gray, brown, or black with a gray patch behind the fin. They are stocky, with a round forehead and almost non-existent beak. They have a large dorsal fin set forward on the body but arches backward. They typically travel in groups of 15-50 individuals, but several hundred have been seen together.
Although rarely seen in Massachusetts, the short-finned pilot whale can be seen off the coast of Barnstable, Essex, and Nantucket counties.
The silver-haired bat is a nocturnal, solitary mammal from the central part of North America. It uses echolocation when flying. Their color is typically black but sometimes dark brown, with the tip of their fur gray. It measures about 10 cm and weighs from 8 to 12 g.
This insectivore eats flies, leafhoppers, moths, mosquitoes, beetles, bugs, and ants. It lives in the forests of North America. Their average lifespan is 12 years, and they migrate to warmer climates in winter.
The silver-haired bat can be found statewide in Massachusetts.
The smoky shrew is a nocturnal mammal that lives in eastern North America. They usually use tunnels from other moles or shrews but rarely dig their own. Their color is grayish-brown with a lighter underbody. They measure about 11 cm with a weight of 5g. This insectivore eats beetles, spiders, bugs, snails, fungi, centipedes, worms, and larvae.
They live in coniferous and deciduous forests, marshes, swamps, and grasslands. Their lifespan is 14 to 17 months. The smoky shrew can be found in Massachusetts’s central and western counties.
The snowshoe hare is also called the varying hare or snowshoe rabbit, and it takes the name because of the large size of the hind feet. Their feet prevent these rabbits from sinking in the snow when hopping and walking. They are covered with fur on the soles for protection against freezing temperatures.
These rabbits turn white during the winter and rusty in the summertime. They can be distinguished by black tufts of hair on the edge of their ears and by the relatively small size of their ears compared with other hares. They usually measure about 36 to 52 centimeters and can weigh 1.3 to 1.7 kilograms as adults. They adapt their diet according to the season.
The snowshoe hare can be found statewide except on the islands of Dukes and Nantucket counties. They usually feed on grass, fens, and leaves during the summer and turn to twigs and bark in winter.
Southern Bog Lemming
The Southern bog lemming is a small mammal from eastern North America. The color varies from red to dark brown and light gray on its underbody. It measures about 13 cm long and weighs about 35 g. This animal eats plants, seeds, stems, and leaves. Their lifespan is 29 months.
This lemming species lives in grasslands, low moist places, deciduous and coniferous forests, wetlands, and marshes. The Southern bog lemming can be found in Franklin, Hampshire, Plymouth, and Worcester counties, although they are listed as a special concern in Massachusetts.
Southern Flying Squirrel
The Southern flying squirrel is a nocturnal mammal that glides from one tree to the next because of the membranes between its front and hind legs. They live in the western part of North America.
Their color is grayish brown, with a white underbody. It measures from 21 to 26 cm (including the tail) and weighs from 45 to 82 g. The Southern flying squirrel is an omnivore and eats nuts, seeds, spiders, acorns, fungi, eggs, insects, shrubs, buds, mushrooms, flowers, and fruits.
They live in deciduous forests, with a lifespan of five to six years in the wild and ten years in captivity. The Southern flying squirrel can be found in every county of the state except Dukes and Nantucket.
Southern Red-backed Vole
The southern red-backed vole is a primarily nocturnal, small mammal from the central part of North America. Its primary color is gray, and they have a red stripe on its back, with an underbody of gray or white.
They measure from 7 to 11.2 cm and weigh 6 to 42 g. This omnivore eats insects, grains, fruits, nuts, seeds, berries, leaves, roots, bark, fungi, and lichens.
This vole species lives in coniferous, deciduous, and mixed forests near water bodies in southern Canada and the northern United States, with a short lifespan of just 10 to 20 months. The Southern red-backed vole can be found in every state except Martha’s Vineyard and Nantucket.
Sowerby’s Beaked Whale
Sowerby’s beaked whale is a medium-sized whale with a body length between 13-18ft and a weight between 1.1-1.4 tons. They do approach boats with breaching, spy hopping, and tail-slapping behavior.
They are blue-gray, gray, or dark brown with a lighter underside. They have a small head for their body and a beak that has a straight mouth. They have a bulge in the front of their blowhole and a small dorsal fin towards their rear.
Sowerby’s beaked whales are rare in Massachusetts but have been seen off Barnstable, Essex, and Nantucket counties.
The sperm whale grows 36-52 ft (11-16m) with a weight between 15-50 tons. They have a dark gray body with a squarish head and a hump instead of a dorsal fin. Their blowhole is slit-like, and they can often be seen lying motionless at the water’s surface. They have a single calf after a long gestation period of 14-16 months.
The sperm whale is endangered in Massachusetts and is rarely seen in the state.
The star-nosed mole is a solitary mammal from eastern North America. Their color ranges from dark brown to black. They measure from 15 to 20 cm and weigh 37 to 76 g. This carnivore eats worms, amphibians, aquatic insects, mollusks, and small fish.
They live in wet lowland areas, forests, and marshes. Their lifespan is 2.5 years in captivity. By using their star-nose, they gather a clear image of their surroundings.
The star-nosed mole can be seen in all counties except Dukes and Nantucket.
The striped dolphin takes its name from the dark stripes running down their bodies’ sides. They have a gray or blue-gray cape on the dorsal side, with lines from the eye to the flipper along their sides. They can also have bars with pink and blue colors on their sides. They grow from 5.9-8.9 ft (1.8-2.7m) and weigh 200-360 lb.
They have some unusual behaviors, able to leap up to 23 ft, with belly flops and somersaults seeming no trouble. They also roto-tail when they come out of the water. This involves moving their tails in circles as they leap out of the water.
The striped dolphin is another rare dolphin in Massachusetts, but when seen, it is normally off the coast of Barnstable, Essex, and Nantucket counties.
The striped skunk is a primarily nocturnal mammal found in the central part of North America. Its color can be black, gray, or brown, and it always has a white stripe on its back, running from its head to its tail. It measures from 52 to 77 cm and weighs from 1.8 to 4.5 kg.
This omnivore eats crickets, grasshoppers, beetles, caterpillars, mice, voles, eggs, and small birds. Their lifespan is seven years.
The skunk lives in open areas, such as grasslands or thin forests, in southern Canada, the United States, and northern Mexico. The striped skunk can be found in almost every county in Massachusetts except Nantucket.
The tri-colored bat is a small, nocturnal mammal found in eastern North America and Central America. It’s one of the native North American mammals. Their colors range from yellowish-brown to reddish-brown. They measure from 30 to 35 mm and weigh 4 to 10 g.
This bat species is an insectivore eating moths, midges, flies, beetles, mosquitoes, and ants. Their lifespan is 4 to 8 years in the wild. It is possible that they could become an endangered species.
They live in partly open places with large trees in forests, grasslands, and urban and suburban areas. The tri-colored bat is listed as endangered in Massachusetts but can be seen statewide.
True’s Beaked Whale
True’s beaked whale measures 15.7-17.7 ft (4.8-5.4m) with a weight between 1.1 and 1.5 tons. They feed on squid and some fish. There have only been a few sightings, so very little is known about their behavior. They are brownish-gray or bluish-gray with a lighter underside. They are medium-sized whales with spindle-shaped bodies. They have a dark patch around each eye and a short beak. They have a bulbous head, and at the blowhole is an indentation. They have a dorsal fin, which is fast.
True’s beaked whale is rare in Massachusetts and is not seen near shore.
The Virginia opossum is the only marsupial found in North America and Central America. This medium-sized animal measures 13-37cm in length and can weigh between 0.3-3.7 kg). It has relatively short legs and typically gray or brownish fur. This animal is known to act as if they are dead as protection against predators.
Their habitats can vary, but they prefer living close to water sources. They can also thrive in urban areas. The Virginia opossum can be found in all counties except Dukes and Nantucket.
The white-beaked dolphin is large for a species of dolphin. They can grow from 7.9-10.2 ft, weighing 400-770 lb. They have white, black, and gray markings, with their tail usually paler. They have a white patch on each side. Their flippers are primarily dark, with a brown or gray beak. They can be found in the St. Lawrence River, the Gulf of St Lawrence, and around Newfoundland.
The white-beaked dolphin is rarely seen in Massachusetts’ waters, mainly off the coast of Barnstable and Essex counties.
White-footed Deer mouse
The white-footed deer mouse is a timid, nocturnal mammal that lives in eastern North America. Their color is reddish-brown, with a dark, broad mark on their back and white on the underbody. It measures 9 to 10 cm (without the tail) and weighs 20 to 30 g. This omnivore eats seeds, nuts, grain, insects, fungi, and fruit.
The deer mouse lives in warm, dry forests and semi-desert areas. Their lifespan is one year in the wild. The white-footed deer mouse can be found statewide in Massachusetts.
The white-tailed deer is a mammal found in the central part of the American continent. They live in most of Mexico, the United States, and Canada’s southern regions in North America. Their color is grayish-brown in the winter and reddish-brown in the summer. They have patches of white on their face, underbody, and tail.
This species of deer measures from 95 to 220 cm and weighs from 45 to 68 kg. This herbivore eats grass, corn, leaves, nuts, twigs, fruits, and fungi. Their lifespan is 4 to 5 years.
They adapt to their environments and live in grasslands, forests, farmlands, and deserts. The white-tailed deer can be found all over the state of Massachusetts.
The woodchuck is a solitary, diurnal rodent. Their color is grayish brown. It measures from 41 to 68 cm (including the tail) and weighs 2 to 6.3 kg. This herbivore eats mainly wild grass, roots, leaves, bark, nuts, flowers, fruit, vegetables, and farming crops. They sometimes eat insects like grasshoppers and snails. Their big front teeth never stop growing, and feeding themselves constantly wears them out, keeping them at the correct size. Humans consider the groundhog a pest because it eats voraciously in the year’s warm months.
They hibernate from October to March and have a lifespan of 6 years in the wild and up to 14 years in captivity.
They are found in flat, open pieces of land (like low-elevation forests and grasslands) in the northern parts. The woodchuck can be found in all counties in the state of Massachusetts except Dukes and Nantucket counties.
Woodland Jumping Mouse
The woodland jumping mouse is a medium-sized rodent, with females slightly larger than males. The average weight is about 17-35 grams, with a length of 205-256 mm (including the tail). They can jump as high as 3 meters (or 9.8 feet) by leveraging their strong feet and long tail. Usually, they prefer a quadrupedal walk to move around. They are mainly nocturnal and prefer forested habitats. The fur of this mouse has several shades of brown, with white feet.
The woodland jumping mouse can be found in Worcester County and the counties west of Berkshire, Franklin, Hampden, and Hampshire.
The woodland vole is a mammal that lives in the eastern part of the United States. They are light or dark brown, with a white or gray underbody. They measure from 83 to 121 cm and weigh 14 to 37 g. Their lifespan is a short three months.
This herbivore eats roots, nuts, seeds, and leaves and lives in deciduous forests. The woodland vole can be seen in every county in Massachusetts except on the islands of Dukes and Nantucket counties.
Source: Massachusetts Government Website
Bryan Harding is a member of the American Society of Mammalogists and a member of the American Birding Association. Bryan is especially fond of mammals and has studied and worked with them around the world. Bryan serves as owner, writer, and publisher of North American Nature.