New York State Mammals Order Rodentia (cont.) Order Lagomorpha
FAMILY: CRICETIDAE New World rats, mice, voles, hamsters, etc. Diverse & species rich Most terrestrial, 1 in NYS is aquatic Muskrat Subfamily Neotominae- deer mice, woodrats et al. Long tails & prominent ears Subfamily Arvicolinae - lemmings & voles Stout bodies, with small, rounded ears, short legs & tails
Southern Red-backed vole Myodes gapperi Habitat: Notes: ID: Woodland, conifer, mossy areas Subsurface runways Found at higher elevations Less dependent on rocky areas than some other voles Can displace Microtus and Peromyscus in wooded habitats Reddish dorsal stripe Tail > hind foot 25 35 g Emarginated postpalatal shelf (vs. Microtus)
Habitat: Notes: ID: Yellow-nosed vole Microtus chrotorrhinus Forested habitats w/ rocks, talus, thick ground cover, accessible water aka Rock vole Yellow face ("ochraceous facial wash"), lighter brown dorsal pelage than Microtus pennsylvanicus (Meadow vole) Tail > hind foot Larger ears than most Microtus species 40 g Dentition
Meadow vole Habitat: Notes: ID: Microtus pennsylvanicus Meadows, grasslands, abandoned fields Above-surface runways Very common Tail much > hind foot, up to twice as long Often the largest vole Short smooth fur, dull, but not grizzled 40 60 g Dentition
Pine vole Microtus pinetorum Habitat: Notes: ID: Forested areas, variety of habitats Pest of orchards in the northeast Subsurface runways Tail <= hind foot Glossy fur (more sheen than Synaptomys cooperi (Southern bog lemming)) 14-37 g Dentition
Southern bog lemming Synaptomys cooperi Habitat: Variety of habitats: grasslands, mixed woodlands, spruce-fir forests, and wetlands Notes: Rare, not often captured ID: Tail <= hind foot Grizzled fur (duller in appearance than Microtus pinetorum (Pine vole)) 35 g Thicker/wider incisors w/ longitudinal groove in front Wider zygomatic arch
Muskrat Ondatra zibethicus Habitat: Found near water Notes: Builds a hut or burrows in stream bank ID: Large vole,1 1.5 kg Laterally flattened tail, stiff hairs on feet Flattened skull Small interorbital length Post-orbital process square
Tips for vole diagnostics First: does it have a large ears? If yes, it s a mouse, not a vole. Microtus pinetorum and Synaptomys cooperi both have short tails (<= hind foot length). Other voles have longer tails, but generally shorter than rats and mice. MIPI has glossy fur, SYCO has grizzled fur If a skin has tail length greater than hind foot, eliminate these two
Tips for vole diagnostics Next, look at fur color looking for yellow on the face (Microtus chrotorrhinus) or red on the back (Myodes gapperi) If it s not MICH or MYGA, and it s medium to large in size, it s probably Microtus pennsylvanicus If it s several times bigger than other voles and has a squared-off postorbial process, it s a muskrat (Ondatra zibethicus)
General tips for specimen ID Always look for the most obvious sign first e.g., ear length or molar shape, to decide whether it s a mouse or a vole before proceeding with ID Short (almost invisible) ears, short tail = vole Long ears, long tail = mouse
FAMILY DIPODIDAE (Rodentia) Jumping mice, birch mice, and jerboa Ricochetal movement (can cover up to 3 feet in one bound) Jumping mice will hibernate through most of winter months Elongated hind limbs and long tail Grooved incisors Infraorbital canal is keyhole shaped
Woodland jumping mouse Napaeozapus insignis Habitat: Forests Notes: Eats fungi, insects, and fruit Hibernates ID: ~20 g Large feet & ankles, jumps 4 m Brown w/ white belly, yelloworange sides, white tip on tail Skull: Grooved incisors, 3 molariform teeth in each upper quadrant
Meadow jumping mouse Zapus hudsonius Habitat: Grassy/weedy fields Notes: Leaps shorter distances than woodland ID: ~20 g Tail lacks white tip, not as strongly tri-colored Skull: Grooved incisors, 4 molariform teeth in each upper quadrant
FAMILY: ERETHIZONTIDAE (Rodentia) New World porcupines Large auditory bullae, but poor vision Large infraorbital canal/foramen Heavily modified digestive systems to accommodate their diet of bark, etc. Mostly arboreal or semi-arboreal Easy ID Dorsal guard hairs are modified into spines or quills
North American porcupine Habitat: Erethizon dorsatum Mainly forests Notes: ID: Pest to logging industry Eats bark, phloem, and cambium of trees Pelage: quills Skull: Large infraorbital foramen, 20 teeth
Porcupine sign