TN10022 ROCK VOLE MICROTUS CHROTORRHINUS
| Species ID | TN10022 |
| Name | VOLE, ROCK |
| Other Common Names | |
| Category | 05 Mammals |
| Elcode | |
| Phylum | CHORDATA |
| Subphylum | |
| Class | MAMMALIA |
| Subclass | |
| Suborder | |
| Order | RODENTIA |
| Family | CRICETIDAE |
| Genus | MICROTUS |
| Species | CHROTORRHINUS |
| Subspecies | |
| Authority | |
| Scientific Name | MICROTUS CHROTORRHINUS |
Comments
The rock vole resembles the meadow vole (Microtus pennsylvanicus) in size but can be easily distinquished by the characteristic orange-yellow color of the nose and cheek *183:1*. Type specimen is an adult male from Ganoga Glen, Luzerne County, Pennsylvania *132:68*. There are no known scientific taxonomic synonyms. The rock vole is also known as the yellow-nosed vole *PA12068*.
| Status Code | Status Translation | References |
| 206 | In need of management | PA12068 |
| County Name | Historical Occurrence | Resident Occurrence | General Occurrence | Seasonal Occurrence | Abundance |
| Blount | 3 | ||||
| Cocke | 3 | ||||
| Sevier | 3 |
| Absent Within Counties | Unknown Within Counties |
Hydrologic Unit Code References
| Quadrangle | Quadrangle Name |
Quadrangle Distribution References
| Ecoregion | Ecoregion Name |
| 211100 |
Ecoregion Distribution References PA4752, PA4960, PA4963
| River Reach | River Reach Name |
River Reach References
Distribution General Comments The geographic range of the rock vole extends across eastern Canada from the Maritime Provices and Laborador to southwest Ontario and northeast Minnesota and continues in a narrow band through the Appalachian Mountains to North Carolina and Tennessee. Restricted habitat preferences of the rock vole have led to widely isolated populations throughtout its range *PA12068:372,183:2*. For example, a distance of 250 miles separates the recorded collections made in Sullivan and Luzerne Counties, Pennsylvania from those in Tucker County, West Virginia. No specimens have been collected from the expanse between these populations though pliestocine cave deposits in Somerset County, Pennsylvania contain remains of rock voles *PA12069*. In Pennsylvania the rock vole is limited to isolated populations in northeastern counties including Luzerne (Ganoga Glen and Lake Rose), Sullivan (Ganoga Lake, Ogdonia Creek, and Normont), Waynea (Island Lake, and Hollow), and Wyoming Counties *PA12070*. Potential rock vole habitat exists along the disjuncted portion of its range which extends through the Appalichian chain of central and south-central Pennsylvania.
General Distribution References PA12068, PA12069, PA12070, 183
Habitat(s): TERRESTRIAL
Comments on General Habitat
The prefered forest types include black spruce-balsam and fir-paper birch *PA4960,PA4961,PA4752,PA4963*. Throughout its range the rock vole prefers cool, moist areas in rock talus. Presence of an herbaceous ground cover and free water, either surface or subsurface flow, are important habitat parameters *183:3,PA12071:49,PA12072:319,132:68,PA12073:100,PA4963:177, PA11866:100*. Rock voles are assoicated with the Canadian and Hudsonian life zones *PA4963:172* but have been shown to occupy transition zone habitat *PA12071:49*,PA12074*. Rock voles are often captured in unexposed sites such as under rock ledges, in spaces between boulders, or in runways under talus *PA12072:319,PA12073:100*. Martell *PA12075 recorded rock voles on selective cut/stands in Ontario but not on clearcuts. In West Virginia rock voles were found to inhabit clearcut areas of northern coniferous and mixed decidious species at higher elevations *PA12071:49*. Because available water has been shown to be an important habitat component it has been surmised that the interception of fog moisture by vegetation and rocks, at higher elevations where rock voles are found, may provide water for direct consumption when other sources may be seasonally scarce *PA12073*:100*. Near Hillsgrove, Sullivan County, Pennsylvania rock vole habitat consisted of rocks, rotting logs and stumps. Tree species present included sugar maple (Acer saccharum), red maple (A. rubrum), black birch (Betula lenta), yellow birch (B. lueta), basswood (tilia americana), hemlock, (Tsuga canadensis), white ash (Frazinus americana), and butternut (Juglans cinera). Birches comprised 505 of the stand, which was described as "browsed out" *250:49*. Grimm and Whitebread *132:68* captured rock voles in Ganoga Glen, in Luzerne County, and described the habitat as a steep-sided, rocky gorge where moss and ferns were abundant, water sources were abundant, and hemlock and northern hardwoods were present. On the summit of North Mountain rock vole habitat included talus areas with small yellow birches, maples, hemlocks, and mountain ashes. Common ground cover species of typical rock vole habitat include reindeer moss (Cladonia alpestric), sphagnum, club moss (Lycopodium sp.), bunchberry (Cornus canadensis), Blueberry (Vaccinium sp.), and raspberry (Rubus sp.) *PA4960:2*. Rocks and talus are an important feature of its habitat throughout its range. Also water either in the form of surface on sub-surface streams is another important component of its habitat. It inhabits sites characterized by an abundance of mosses and forbs within forested areas *183,240*. They may also use recent clearcuts *183*. Rocks and talus are an important feature of its habitat throughout its range. Also water either in the form of surface on sub-surface streams is another important component of its habitat. It inhabits sites characterized by an abundance of mosses and forbs within forested areas *183,240*. They may also use recent clearcuts *183*. ROCK VOLES USUALLY ARE FOUND IN ROCKY HABITATS IN OR NEAR FORESTED AREAS. IN GREAT SMOKY MOUNTAINS NATIONAL PARK, THEY LIVE AT ELEVATIONS FROM ABOUT 2600 FEET TO THE TOPS OF THE HIGHEST MOUNTAINS, ALTHOUGH THEY ARE MOST OFTEN ENCOUNTERED ABOVE 3000 FEET. SURFACE WATER OR SUBSURFACE STREAMS ARE OTHER IMPORTANT COMPONENTS OF THE HABITATS, AS ARE MOSSES AND FORBS. *TN6213*
General Habitat References
PA4960, PA4961, PA4752, PA4963, 183, PA12071, PA12072, 132, PA12073, PA11866, PA12074, PA12075, 250, TN6213
| Forest Size Class Association |
| Unstocked |
| Pole |
| Seedling/Sapling |
| Mature |
| Over Mature |
Forest Size Class Association References
PA4752, PA4960, PA4961, PA4963, 183
| Society of American Forester's Type Associations | Seral Stage | Canopy Closure |
References on SAF Type Association
| Land Use/Land Cover Associations |
| Deciduous Forest Land |
| Evergreen Forest Land |
| Mixed Forest Land |
| Streams and Canals |
| Forested Wetland |
| Beaches |
| Bare Exposed Rock |
| Transitional Areas |
| Mixed Barren Land |
| Forest Land |
Land Use/Land Cover Association References
4920, PA4752, PA4960, PA4961, PA4963, 183
| National Wetlands Inventory Associations | Class | Modifier | Special Modifier |
| Palustrine | Forested | ||
NWI Association References
47,
| Animal/Plant Associations |
Animal/Plant Association References
183
Habitat Evaluation Procedures Comments on HEP
HEP References
| Potential Natural Vegetation Associations |
PNV References
| USFS Associations |
USFS References
| Tennessee Habitat Associations | Habitat Value | Translation |
References on TENHAB Association
| Habitat Relationships | Special Habitat Relationships |
References on Habitat Relationships
Trophic| References | |
| HERBIVORE | 4920 |
| herbivore | PA4963 |
| Lifestage | Food Item Consumed | Part of Food Item |
| Adult | Plants | |
| Adult | Eumycophyta | |
| General | Plants | |
| General | Eumycophyta | |
| Juvenile | Plants | |
| Juvenile | Eumycophyta | |
| General | Plants | Bole/Stem |
| General | Bryophyta | Bole/Stem |
| General | Lichens | Bole/Stem |
| General | Tracheophyta (Vascular Plants) | Bole/Stem |
| General | Spermopsida | Bole/Stem |
| General | Monocotyledoneae | Bole/Stem |
| General | Poaceae | Bole/Stem |
| General | Free-living Flatworms | Larva stage |
| General | Lepidoptera | Larva stage |
| General | Insects | Larva stage |
| Adult | Plants | Bole/Stem |
| Adult | Bryophyta | Bole/Stem |
| Adult | Lichens | Bole/Stem |
| Adult | Tracheophyta (Vascular Plants) | Bole/Stem |
| Adult | Spermopsida | Bole/Stem |
| Adult | Monocotyledoneae | Bole/Stem |
| Adult | Poaceae | Bole/Stem |
Comments on General Food Habits
An insect was readily accepted by an individual under laboratory conditions, suggesting this species may be more omnivorous than commonly believed *PA4963*.
Comments on Adult Food Habits
An insect was readily accepted by an individual under laboratory conditions, suggesting this species may be more omnivorous than commonly believed *PA4963*.
Comments on Juvenile Food Habits
Data not separated by age class, although it can be reasonably assumed that there are no difference between juveniles and adults, as for most small mammals *4900*.
| References/Lifestage | Reference Numbers |
| General | 4920, PA4963, 183 |
| Adult | 4920, PA4963, 183 |
| Juvenile | 4920, PA4963, |
| Lifestage | Environmental Association |
| General | Terrestrial Features: Rock outcrops |
| General | Aquatic Features: Springs [flowing] |
| General | Soil Moisture: Moist |
| General | Vegetations Successional Stage: Climax forest |
| General | Terrestrial Features: Talus |
Comments on General Environmental Associations
There are only sporadic listing of foods, and only the following list has been noted: mitrewort, violet bunchberry, mayflowers, clinton's lily, lily-of-the valley, blueberry, raspberry, mushroom PA4963,PA4962*. Rock outcrops form an important component of their habitat *PA4963,4811*. They are found in the transition zone between rocks and forest *PA4963*. They appear to prefer young forest communities with a thick shrub layer *PA4962*. They occur in boreal forest rocky areas *PA4963,PA4962*. It is found in habitats of mixed deciduous red spruce forest along with rock and talus and a ground cover of mosses and ferns *183* may also use recent clearcuts *183*. It is found in habitats of mixed deciduous red spruce forest along with rock and talus and a ground cover of mosses and ferns *183* may also use recent clearcuts *183*.
Comments on Limiting Environmental Associations
Comments on Feeding Adult Environmental Associations
There are only sporadic listing of foods, and only the following list has been noted: mitrewort, violet bunchberry, mayflowers, clinton's lily, lily-of-the valley, blueberry, raspberry, and mushroom *PA4963,PA4962*.
Comments on Resting Adult Environmental Associations
Rock outcrops form an important component of their habitat *PA4963,4811*. They are found in the transition zone between rocks and forest *PA4963*, and appear to prefer young forest communities with a thick shrub layer *PA4962*. They occur in boreal forest in rocky areas *PA4963,PA4962*.
| References/Lifestage | Reference Numbers |
| General | PA4962, PA4963, 183 |
| Feeding Adult | PA4962, PA4963, |
| Resting Adult | PA4962, PA4963, |
Physical Description: This is a robust mirotine rodent, closely resembling the meadow vole in form. The dorsal pelage is dark brown with a mixture of black-tipped hairs. Ventrally, it is dull to silvery gray, with orange to dull fulvous coloration on the face around the nose and eyes. There is no sexual variation. The total body length is 165 mm (152 to 185), the tail length 47 mm (42 to 53), the hindfoot 20 mm (19 to 23), the ear notch 13 mm (mn 12-16 mm), and the weight 30 to 40 grams (mn 15.4 to to 43.7 grams). Reproduction: In Minnesota, breeding begins from May to June, with the duration uncertain. Behavior: This species is diurnal *PA4871*. It is active throughout the day and night, while less active during afternoon hours, *PA4963*. Foraging apparently occurs in isolated colonies, commonly among rocky outcrops where a shallow burrow can be found by winding toward the perimeter vegetation. This species feeds primarily on forbs, with little preference for grasses *PA4963,4920*. Limiting factors: This species is limited by suitable habitat particularly rock outcrops *PA4963*. The rock vole is a meadium sized vole which closely resembles the meadow vole (Microtus pennsylvanicus), but no other vole has the characteristic orange-yellow colored nose and cheek. This color is most prominant on the snout and decreses towards the ears. The upper parts are grayish bister to bright-glossy bister with black-tipped hairs. Some individuals have a yellowish tint on the rump. The eyes are small and the ears protrude slightly beyond the body fur. The inscive formania of adult rock voles are shorter (generally <4.74mm) and not markedly tapered as in the meadow vole. The dentition of the rock vole; three closed dentive triangles, an anterior loop, and no posterior loop of the M3, is an identifying characteristic *PA12068:37001,183:1*. Measurements for specimens collected in Pennsylvania are given in reference *132:68*. The rock vole is native to Pennsylvania. The earliest report of the rock vole in Pennsylvnaia, during recent time, is 1935 from Sullivan County. Pleistocene cave deposits in Bradford County have been shown to hold remains of rock voles, indicating a wider prehistoric range *PA12069,PA12070*. Behavior: There is only limited information available concerning the behavior of the rock vole. Relatively unchanging proportions of three red-backed voles (Clethronmys gapperi) to one rock vole, in favorable rock vole habitat, during high and low population levels indicates a lack of competition or exclusion (Martain 102). In captive conditions no agression was displayed between rock voles and red-backed voles *PA4963:180*. Rock voles live in small colonies *PA11380:155* and formation of nests while in captivity suggests this in the wild *PA12073:102*. Martian suggests that rock voles are diurnal and most active in morning. Timm *PA4963:180* indicated that trapping data showed rock voles to be active both day and night but less during afternoon hours. Retention of fecal pellets may indicate the use of a latrine area in subsurface burrows *PA12083:101*. Rock voles spend the vast majority of their time in subterranean activity *PA12072:320*. Reproduction: Reproduction data for the rock vole is limited. Average litter size in the rock vole, from data in Minnesota, is 3.5. Females born in late spring produced litters during their first summer. Some females will have 3 litters per year *PA4963:177*. Breeding occurs from late March through mid-October. Sexual maturity in females and males occurs at about 30 grams. Litter sizes are largest in June, with larger litter sizes at more northern latitudes *PA12073:115*. Weight at birth has been reported as 3-4 gms *7359*. The gestation period is 19-21 days *12080*. Population: The population biology of the rock vole is virtually unknown and limited to scattered remarks in the literature. Rock voles are known to exist in small colonies *45:128* and exhibit a 50:50 sex ratio *PA12097:47*. Populations of rock voles are rare, islolated, and recorded only from four northeastern counties within Pennsylvania *PA12068:372*. Limiting Factors: Several components of typical rock vole habitat appear to act as limiting factors. The presence of rocks or talus, running water in the form of surface or subsurface flow, and an herbaceous ground cover appear to be essential habitat require- ments *183:3,PA12068:372,PA11866:100,PA4963:178,PA12073:101,PA12081:498* Potential rock vole habitat may exist between the known populations in northeastern Pennsylvania and those in West Virginia. Increasing development, partcularly in northeastern Pennsylvania may destroy rock vole habitat *PA12068:372*. Physical description: This species is a medium sized vole with external measurements of: total length 140-185 mm, tail 42-64 mm, hindfoot 18-24 mm, and weight 30-48 grams. The upperparts are grayish bister to bright glossy bister with black-tipped hairs. The face has a yellowish to dull orange-rufous wash, which is most prominent on the snout and decreases in intensity toward the ears. The extent and intensity of pigmentation vaires with age and geographic locality. M. c. carolinesis is darker than the other subspecies of Microtus chrotorrhinus, which are grayer *183,134*. Reproduction: The breeding season is from early spring to late fall. The gestation period is 19-21 days. The litter size rages form 1-7 with an average of 3.7. There is an age parity effect of increasing litter size as exhibited by larger heavier, and presumably older females. Reproduction in females generally occcurs in voles more than 140 mm (total body length) and 30 grams body weight. The males reach a preproductive state when the body length is greater than 150 mm and body weight is greater than 30 grams. A post-partum estrus is indicated in rock voles *183*. Behavior: Rock voles are primarily dinural and are most active in the morning. Rock voles spend a considerable amount of time in subterranean activities. They are often caught in subsurface runways among rocks *183*. Limiting factors: Rock voles are prey for bobcat (Felis rufus), timber rattlesnakes (Crotalus horridus), Copperheads (Agkistrodon contortrix), and short-tailed shrew (Blarina brevicauda). Parasites include Acari, Diptera, Fleas, Cestodes, and Nematodes *183*. Terrestrial associations: Rock voles share their subterranean habitats with red-backed mouse (Clethrionomys gapperi) these two species apparently don't compete or exclude each other. Other common habitat associates of rock voles include the masked shrew (Sorex cinereus), smoky shrew (S. fumeus), rock shrew (S. dispar), short-tailed shrew (Blarina brevicauda) and deer mouse (peromyscus maniculatus) *183*. Physical description: This species is a medium sized vole with external measurements of: total length 140-185 mm, tail 42-64 mm, hindfoot 18-24 mm, and weight 30-48 grams. The upperparts are grayish bister to bright glossy bister with black-tipped hairs. The face has a yellowish to dull orange-rufous wash, which is most prominent on the snout and decreases in intensity toward the ears. The extent and intensity of pigmentation vaires with age and geographic locality. M. c. carolinesis is darker than the other subspecies of Microtus chrotorrhinus, which are grayer *183,134*. Reproduction: The breeding season is from early spring to late fall. The gestation period is 19-21 days. The litter size rages form 1-7 with an average of 3.7. There is an age parity effect of increasing litter size as exhibited by larger heavier, and presumably older females. Reproduction in females generally occcurs in voles more than 140 mm (total body length) and 30 grams body weight. The males reach a preproductive state when the body length is greater than 150 mm and body weight is greater than 30 grams. A post-partum estrus is indicated in rock voles *183*. Behavior: Rock voles are primarily dinural and are most active in the morning. Rock voles spend a considerable amount of time in subterranean activities. They are often caught in subsurface runways among rocks *183*. Limiting factors: Rock voles are prey for bobcat (Felis rufus), timber rattlesnakes (Crotalus horridus), Copperheads (Agkistrodon contortrix), and short-tailed shrew (Blarina brevicauda). Parasites include Acari, Diptera, Fleas, Cestodes, and Nematodes *183*. Terrestrial associations: Rock voles share their subterranean habitats with red-backed mouse (Clethrionomys gapperi) these two species apparently don't compete or exclude each other. Other common habitat associates of rock voles include the masked shrew (Sorex cinereus), smoky shrew (S. fumeus), rock shrew (S. dispar), short-tailed shrew (Blarina brevicauda) and deer mouse (peromyscus maniculatus) *183*.
References for Life History Codes
83, 4920, PA4963, 132, 183, PA4871, PA12068, PA12069, PA12070, PA11380, PA12073, PA12083, PA12072, 45, PA12097, PA12068, PA11866, PA12081, 134
Comments on Life History Codes
| Result | Management Action | ||
| Beneficial | Maintaining undisturbed/undeveloped areas | ||
| Beneficial | Maintaining wilderness environment | ||
| Beneficial | Creating/maintaining rock piles | ||
| Beneficial | Maintaining overmature forests | ||
| Beneficial | Timber harvesting - clearcutting | ||
| Adverse | Applying herbicides | ||
| Adverse | Applying pesticides | ||
| Adverse | Applying insecticides |
| References/Result | Reference Numbers |
| Adverse | 183 |
| Beneficial | 183 |
Comments on Management Practices
Management for the rock vole should concentrate on identification of potential habitat sites within the state by comparison with the components of known rock vole habitat in the northeastern counties. Protection of the known population sites and any potential habitat is essential considering the lack of available life history data on this species within Pennsylvania.
45* Burt, W.H. 1969. Mammals of the Great Lakes Region. Univ. of Michigan Press, Ann Arbor, Mich:246. 47* Burt, W.H., Gossenheider, R.P. 1976. A field guide to the mammals. Houghton Mifflin Co., Boston, Mass:289. 83* 1978. North American furbearers, their management, research and harvest status 1976. Inter. Assoc. Fish and Wildl. Agencies Deems, E.F., Jr., Pursley, D. (eds.).:171. 132* Grimm, W.C., Whitebread, R. 1952. Mammal survey of northeastern Pennsylvania. Pittman-Robertson Project 42-R. Penn. Game Comm., Harrisburg, Penn:82. 134* Hall, E.R. 1981. The Mammals of North America. 1,2. John Wiley and Sons, New York, New York:1271. 183* Kirkland, G.L., Jr., Janne, F.J., Jr. 1982. Microtus chrotorrhinus. Mammalian Species No. 75. Am. Soc. Mammal.,:6. 250* Roslund, H.R. 1951. Mammal survey of northcentral Pennsylvania. Pittman-Robertson Project (37-R). Penn. Game Comm., Harrisburg, Penn:55. 4920* Banfield, A.W. 1974. The Mammals of Canada. Univ. of Toronto Press, Toronto & Buffalo:438. PA4752* Buech, R.R., Timm, R.M., Siderits, K. 1977. A second population of rock voles, Microtus chrotorrhinus, in Minnesota with comments on habitat. Can. Field-Nat. 91:413-414. PA4871* Martin, R.L. 1971. Interspecific associations of rock voles. Beta Kappa Chi Bull. 30(2):5-7. PA4960* Timm, R.M. 1974. Rediscovery of the rock vole (Microtus chrotohinus) in Minnesota. Can. Field-Nat. 88:82. PA4961* Timm, R. M. 1975. Distribution, natural history, and parasites of mammals of Cook County, Minnesota. Bell Mus. Nat. Hist., University Minn. Occas. Pap. No. 14. PA4962* Timm, R.M. 1980. Habitat requirements of microtine rodents in Minnesota. Proc. Symp. Mammal Ecol., Habitat Manage. PA4963* Timm, R. M., Heaney, L.R., Baird, D.D. 1977. Natural history of rock voles (Microtus chrotorrhinus) in Minnesota. Can. Field-Nat. 91:177-181. PA4969* Unknown. Checklist of North American mammals north of Mexico. Texas Tech Univ. Occas. Papers. 28:1-14. TN6204* TWRA. Tennessee Wildlife Resources Commission Proclamations 94-16 and 94-17. Wildlife in Need of Management & Endangered & Threatened Wildlife. Sept. 27, 1994 TN6213* Choate, J.R., J.K. Jones, Jr., C. Jones. 1994. Handbook of Mammals of the South-Central States. Louisiana State University Press. Baton Rouge, LA. PA10861* Jones, J.K., Carter, D.C., Genoways, H.H., Hoffman, R.S., Rice, D.W., Jones, C. 1986. Revised checklist of North American mammals north of Mexico, 1986. Occasional Papers, The Museum Texas Tech University, No. 107. Texas Tech Univ. Lubbock, TX. 22 pp. PA11380* not found in Bibliography PA11866* not found in Bibliography PA12068* not found in Bibliography PA12069* not found in Bibliography PA12070* not found in Bibliography PA12071* not found in Bibliography PA12072* not found in Bibliography PA12073* not found in Bibliography PA12074* not found in Bibliography PA12075* not found in Bibliography PA12081* not found in Bibliography PA12083* not found in Bibliography PA12097* not found in Bibliography