Mammals of Connecticut
The mammals most often spotted in Connecticut, ranked by recent research-grade observations.
Most-observed mammals in Connecticut
White-tailed Deer
Odocoileus virginianus
4,042 observations
Eastern Gray Squirrel
Sciurus carolinensis
3,761 observations
Eastern Cottontail
Sylvilagus floridanus
2,355 observations
Bobcat
Lynx rufus
1,706 observations
Eastern Chipmunk
Tamias striatus
1,618 observations
Red Fox
Vulpes vulpes
1,416 observations
Common Raccoon
Procyon lotor
1,249 observations
Coyote
Canis latrans
1,141 observations
American Black Bear
Ursus americanus
996 observations
Groundhog
Marmota monax
967 observations
Virginia Opossum
Didelphis virginiana
902 observations
American Beaver
Castor canadensis
709 observations
American Red Squirrel
Tamiasciurus hudsonicus
551 observations
Striped Skunk
Mephitis mephitis
378 observations
Northern Short-tailed Shrew
Blarina brevicauda
277 observations
Muskrat
Ondatra zibethicus
241 observations
White-footed Mouse
Peromyscus leucopus
187 observations
Domestic Cat
Felis catus
177 observations
North American Porcupine
Erethizon dorsatum
165 observations
American Mink
Neogale vison
156 observations
Harbor Seal
Phoca vitulina
147 observations
Gray Fox
Urocyon cinereoargenteus
144 observations
Grey Seal
Halichoerus grypus
128 observations
Big Brown Bat
Eptesicus fuscus
108 observations
North American River Otter
Lontra canadensis
105 observations
Eastern Meadow Vole
Microtus pennsylvanicus
104 observations
Brown Rat
Rattus norvegicus
99 observations
Southern Flying Squirrel
Glaucomys volans
93 observations
Eastern Mole
Scalopus aquaticus
57 observations
Moose
Alces alces
50 observations
Long-tailed Weasel
Neogale frenata
43 observations · iNaturalist
Fisher
Pekania pennanti
42 observations
Eastern Red Bat
Lasiurus borealis
40 observations
Masked Shrew
Sorex cinereus
29 observations
American Ermine
Mustela richardsonii
24 observations · iNaturalist
Star-nosed Mole
Condylura cristata
21 observations
House Mouse
Mus musculus
18 observations
Humpback Whale
Megaptera novaeangliae
17 observations
Harp Seal
Pagophilus groenlandicus
14 observations · iNaturalist
Tamanend's Bottlenose Dolphin
Tursiops erebennus
14 observations · iNaturalist
Northern Meadow Jumping Mouse
Zapus hudsonius
13 observations
Hairy-tailed Mole
Parascalops breweri
13 observations
Woodland Vole
Microtus pinetorum
12 observations
Silver-haired Bat
Lasionycteris noctivagans
9 observations
Domestic Dog
Canis familiaris
7 observations · iNaturalist
Common Dolphin
Delphinus delphis
6 observations
Fin Whale
Balaenoptera physalus
6 observations
Eastern Deermouse
Peromyscus maniculatus
6 observations
Eastern Woodland Jumping Mouse
Napaeozapus insignis
5 observations
Smoky Shrew
Sorex fumeus
5 observations