Distribution, habitat use, and identification of masked shrews
New York State Mammals - · PDF fileFAMILY: SORICIDAE “red-toothed shrews”...
Transcript of New York State Mammals - · PDF fileFAMILY: SORICIDAE “red-toothed shrews”...
• Marsupial
– Only marsupial north of Mexico
Common Name: Virginia opossum
Scientific Name: (Didelphis virginiana)
Virginia opossum
(Didelphis virginiana)
• Habitat: woodlots, suburban, urban
• Omnivorous
• “Plays opossum”
• Plays dead to avoid threatening
situations
• Naked prehensile tail
• Fur gray-silver, white on head
• 13 nipples within pouch
• Skull contains 50 teeth
I 5/4 C 1/1 P 3/3 M 4/4
FAMILY: SORICIDAE “red-toothed shrews”
– Pigmented teeth
– Smallest mammals in the world
– Mainly insectivorous
– Largest/most widely distributed family of insectivores
– Extremely high metabolism
– Most have musk glands
FAMILY: SORICIDAE
• Masked Shrew (Sorex cinereus)*
• Pygmy Shrew (Sorex hoyi)
• Long-tailed Shrew (Sorex dispar)
• Smoky Shrew (Sorex fumeus)*
• N. Short-tailed Shrew (Blarina brevicauda)*
• Least Shrew (Cryptotis parva)
• Water Shrew (Sorex palustris)*
*Specimens we have in lab
Masked shrew
(Sorex cinereus)
• Habitat: forest dweller, primarily moist woods (occupies arid areas in some regions)
• Tail makes up ~40% of total length, tail tip usually black
• Usually brown pelage
Pygmy shrew
(Sorex hoyi)
• Habitat: Boreal regions
• One of the smallest terrestrial mammals on Earth (2.1 grams)
• Longer snout than masked shrew
Long-tailed shrew
(Sorex dispar)
• Habitat: Rocky outcrops or forest with many rocky areas
• Adapted to life within rocks (rare):
1) long tail for climbing
2) long rostrum and pointed incisors for extracting inverts from crevices
• Dark slate coloring
• Tail length > 48 mm
Smoky shrew
(Sorex fumeus)
• Habitat: Moist woods with
heavy leaf litter
• Fairly common
• Smoky or gray colored
• Tail length < 48mm
• Skull and body more
robust than
long-tailed shrew
Least shrew
(Cryptotis parva)
• “bee shrew”: sometimes live in abandoned bee hives
• Habitat: Brushy/grassy areas
• NYS = northern extent of geographic range
• Most social shrew
• Virginia: up to 25
in one nest
• Small shrew with short tail
• < 45% of total length
Northern short-tailed shrew
(Blarina brevicauda)
• Habitat: Variety of habitats
• woodlands, grassy meadows and yards
• Poisonous saliva
• catch invertebrate prey
• subdue large prey such as mice and voles
• Very large shrew with short tail compared to body
• Dark slate colored
• Hair has brown tips
Water shrew
(Sorex palustris)
• Habitat: Near small streams or creeks
• Semi-aquatic: Uses water for foraging and escaping predators
• Adaptations to aquatic lifestyle:
• fur traps air bubbles
• stiff fringes of hair on back feet to assist with swimming
• Large shrew
• Bicolored tail
• Black or dark gray fur
Sorex hoyi
Sorex fumeus
Sorex cinereus 100 mm TL 80 mm 40 mm tail 30 mm 2 – 5 g 1 – 5 g
4 obvious unicuspids 3 obvious unicuspids
115 mm TL 115 mm 55 mm tail 40 mm 3 - 8 g 6 - 11 g
Sorex dispar
Side-by-side Comparisons
Slender, dark grey
Heavy-bodied, Grey-brown
Masked Shrew Pygmy Shrew
Long-tailed
Shrew Smoky Shrew
Side-by-side Comparisons
120 mm TL 70 mm 25 mm tail 30 mm 18 - 22 g 5 - 10 g
Cryptotis parva Blarina brevicauda
Large,
“short-tailed”
shrew
small,
“short-tailed”
shrew
Sorex palustris
Black/greyish back; Stiff fringes of hair on long hind feet (fl = 18 mm) Water Shrew
FAMILY: TALPIDAE
• Eastern Mole (Scalopus aquaticus)
• Hairy-tailed Mole (Parascalops breweri)
• Star-nosed Mole (Condylura cristata)
**A major distinguishing factor between
moles & shrews – moles have
larger/longer forefeet for digging.
FAMILY: TALPIDAE
Adapted for fossorial lifestyle:
1. modified forelimbs
2. keeled sternum- allows for attachment of large pectoral muscles
3. reduced external pinnae and eyes
4. short velvet-like, non-directional fur allows for movement in both directions
Eastern mole
(Scalopus aquaticus)
• Habitat: Prefers moist, sandy soils
• Can live in drier climates and more coarse soils
• Uncommon in NY
• Has webbing between foretoes (not aquatic)
• Large mole, tail naked or sparsely haired
Hairy-tailed mole
(Parascalops breweri)
• Habitat: Variable, most abundant in light soils with vegetative cover
• Has vibrissae on snout and edge of palms to serve a tactile function
• Smaller mole, hairy and fleshy tail
Star-nosed mole
(Condylura cristata)
• Habitat: Prefers moist or wet soils, most aquatic mole
• 22 fleshy appendages on nose with over 25,000 Eimer’s organs
• Tactile & electromagnetic
• Unique star-nose
• Long tail
• Black to blackish brown pelage