Am. Midl. Nat. 164:61–73 Assessing the Distribution of Eastern Moles (Scalopus aquaticus) in Canada in Relation to Loam Soils and Forest Cover LOUISE E. RITCHIE1 AND JOSEPH J. NOCERA Ontario Ministry of Natural Resources, Trent University, DNA Building, 2140 East Bank Drive, Peterborough K9J 7B8 ABSTRACT.—We assessed the distribution of Eastern moles Scalopus aquaticus in relation to loam soils under the hypothesis that the species’ Canadian distribution is limited by soil type. We also explore the relationship between mole occurrence and the amount of forest cover at a local (49 m) and landscape (305 m) scale. We resurveyed 46 sites dispersed across much of the species’ Canadian range in southern Ontario. These sites initially were inspected for mole sign (e.g., surface tunnels and earth mounds) in 1997, allowing us to compare between study periods to assess changes in species distribution. Eastern moles were eight times more likely to occur at sites with loam or sandy loam soils than at sites with other soil textures (e.g., coarse sands, clays). The likelihood of mole sign no longer occurring at a site in 2008 increased in the absence of loam or sandy loam soils. At sites with loam or sandy loam soils, including the proportion of forest cover within the surrounding landscape increased our ability to discriminate between sites with and without mole sign. We noted a 26% decrease in mole occurrence across our study area since it was surveyed more than a decade ago. INTRODUCTION Talpid moles are relatively common in North America, yet they remain surprisingly understudied and are among the most poorly understood North American mammalian taxa (Hartman and Yates, 2003). The Eastern mole (Scalopus aquaticus Linnaeus, 1758) has the largest range of all North American moles (Yates and Schmidly, 1978). It is a conservation concern in several states (Colorado, West Virginia and Wyoming) and has a very limited distribution within Canada (NatureServe, 2008). The Canadian race is geographically restricted to the vicinity of Essex County and Chatham-Kent municipality in Southern Ontario (see Waldron et al., 2000) and has the largest individuals of the species (Banfield, 1974). Currently, there are few quantitative data describing the occurrence patterns, habitat associations and population stability of Eastern moles. This species is the most subterranean of North American moles (Banfield, 1974), rarely straying from underground tunnel networks. Individuals rarely are observed directly but their tunnelling behaviour provides an index of species occurrence and activity. Such surface indices are frequently used for broad scale studies of species abundance and distribution (Hartman and Krenz, 1993; Rosenblatt et al., 1999; Duhamel et al., 2000; Waldron et al., 2000; Berthier et al., 2005; Delattre et al., 2006). Eastern moles construct two distinct types of tunnels; surface tunnels (,10 cm) that are foraging runways and deep (10–40 cm) tunnels that are less noticeable, more permanent structures. Deep tunnels are typically associated with earth mounds caused by animals piling soil removed during tunnel construction. Eastern moles are intolerant of openings in their burrow system and will persistently repair damaged tunnels (Hartman and Yates, 2003). Soil type, condition and moisture levels may be important limiting factors affecting mole distribution. Individuals of the species reportedly prefer moist loams, may use sandy soils, 1 Corresponding author: e-mail: [email protected] 61 The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:31 61 62 THE AMERICAN MIDLAND NATURALIST 164(1) but avoid clay, stony or gravely soils and arid lands (Arlton, 1936; summarized in Yates and Schmidley, 1978; Waldron et al., 2000). However, quantitative data for these relationships are lacking because authors fail to provide support or cite largely descriptive studies that did not quantify the relationship (Arlton, 1936; Davis, 1942; Banfield, 1974; Yates and Schmidly, 1978; Hartman and Yates, 2003 and references therein). It has been suggested that the distribution of Eastern moles may be affected by proximity to forest cover. Banfield (1974) indicated that the species ‘‘prefers moist friable loams in open woodlands and pastures.’’ Waldron et al. (2000) found mole signs most frequently in forested areas, along hedgerows, watercourses and open drains. Species are influenced in different manners by processes operating at different scales, resulting in the emergence of scale-dependent patterns (Wiens, 1989). The effects, if any, of wooded areas on the distribution of Eastern moles remains relatively unexplored. The objective of our study was to evaluate whether the distribution of Eastern moles coincides with that of loam and sandy loam soils. We explored whether the presence of mole activity was associated with remnant forest cover at two different spatial scales in a region dominated by agriculture. We used decade old mole survey data from our study area (collected in 1997, Waldron et al., 2000) to indicate population stability at the north-eastern edge of the species’ range. METHODS We surveyed 46 sites in the eastern deciduous forest region of southern Ontario (Fig. 1; Rowe, 1972) for fresh signs of mole activity (i.e., tunnels and earth mounds). Essex County encompassed the large majority (41/46) of our survey sites. Essex is dominated by agricultural lands and has ,10% forest cover (Essex Region Conservation Authority, 2002a, b; Dobbie et al., 2007). The county has ridges of gravely and sandy soils overlaying a smooth clay plain and limestone bedrock. These soil conditions originated from the region’s topographical history during which glaciers moved through the region and created lakes (Richards et al., 1949). This region has the warmest temperatures in Ontario and has relatively little annual precipitation (,70 cm). The survey sites were originally selected and assessed for mole sign in 1997 (Waldron et al., 2000); our return in 2008 enabled us to assess the stability of mole sign between these two survey periods. The surveys in 1997 occurred during the summer and fall field season, but no exact dates are available (G. Waldron, pers. comm.). In 2008, all surveys except one were conducted between 16 and 29 Sep. 2008; Fish Point Provincial Nature Reserve was surveyed in mid Nov., 2008. We were denied access to resurvey two sites. Survey sites varied in size and by type of land use (e.g., woodlots, fields, manicured lawns). We use survey site as our sampling unit during analysis. To establish a repeatable survey method while maintaining a similar survey effort between studies, we used the following survey protocol: (1) where pathways or trails were available, we walked the route that would allow us to cover the largest portion of the property; (2) if no trails were apparent, we walked a 500 m transect through the site; (3) if the property dimensions prevented us from walking a single 500 m transect, we walked transect segments summing to 500 m. Trails and coordinates recorded for transect ends provide more clearly defined survey routes for future monitoring efforts. Mole presence was recorded upon the first encounter of fresh mole sign and a geographic position was recorded using a hand-held GPS unit. Fresh mole sign consisted of earth mounds or surface tunnels that easily gave way when slight pressure was applied. Suspected tunnels were confirmed by feeling for tunnel passages. The mole sign within our study area could safely be attributed to Eastern moles because they are not The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:31 62 2010 RITCHIE & NOCERA: EASTERN MOLE DISTRIBUTION 63 FIG. 1.—Study sites within Essex, Middlesex (Strathroy) and Elgin (Rodney) Counties and the Municipality of Chatham-Kent where the presence or absence of mole signs were recorded during field surveys in 1997 and 2008 sympatric with Hairy-tailed moles (Parascalopus breweri) in Canada, and summer and fall livetrapping efforts within Essex County (.500 trap nights) resulted in the capture of only Eastern moles. Generally mole sign is more easily and quickly detected in clearings with low vegetation than in forested areas with uneven terrain or dense ground vegetation. However, our survey methods reduce the effects of this possible bias; we surveyed each site until we either encountered signs of mole activity or until the entire site had been surveyed. Typically, this means that additional time and effort was spent at sites where mole sign might be the most difficult to detect. The presence of suspected surface tunnels was confirmed by inserting a finger or stick into the tunnel passage. At a smaller scale, the estimated proportion of wooded area may be less accurate due to the relative effect of small wooded patches unaccounted for by the initial definition used during the creation of the wooded area data layer. No such discrepancy was obvious during field visits. To examine mole distribution in relation to soil characteristics, we classified 19 soil types into six broader categories based on: geological parent material, drainage and general soil The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:31 63 64 THE AMERICAN MIDLAND NATURALIST 164(1) description (Hoffman et al., 1964; Schut, 1992). The six categories (Soil Type) were: Fox Sandy Loam (n 5 8), Harrow Loam and Sandy Loam (n 5 7), Berrien Sandy Loam or Burford Loam (n 5 8), sands (Berrien, Eastport and Plainfield Sand, n 5 6), very fine textured sands/sandy loams and silt loams (n 5 10, Tuscola Fine Sandy Loam subset 5 3) and clays, marshes and wetlands (n 5 7). We also defined two broader soil groups identifying soil types as loam/sandy loam (n 5 29, including fine sandy loam) or not (n 5 17). Several of the sites were initially classified as soil spot phases (Parkhill Loam – Red Sand, Caistor Clay Sand, Brookston Clay Sand; Richards et al., 1949). Soil conditions within spot phases are more variable due to the presence of scattered sandy knolls, therefore these sites were assigned based on local soil conditions. Tuscola Fine Sandy Loam was classified as ‘Loam’. We used univariate logistic regression models to select between using a six level or binary soil classification during subsequent analyses. To evaluate mole response to local and landscape forest cover, we used logistic regression to assess the correlation between mole occurrence and the proportion of forest cover within an estimated mean home range size (49 m radius, 0.75 ha, ‘Local Forest’) and an estimated dispersal distance (305 m radius, ‘Landscape Forest’). Forest cover at these two scales was calculated using a Geographic Information System data layer adopted from the Southern Ontario Ecological Land Classification (Lee et al., 1998). We used the center of the survey site when determining forest cover in the surrounding area. Although male Eastern moles typically have larger home ranges than females (1 ha and 0.3 ha respectively; Harvey, 1976), we used a home range size averaged across both sexes for our calculations because outside the breeding season, the observed sex ratio likely does not differ from 1:1 (0.75 ha; Harvey, 1976; Hartman, 1995a). We use a dispersal distance of 305 m to delimit a landscape extent for forest cover. This radius was estimated from Townsend’s moles (Scapanus townsendii) because little is known about the dispersal behaviour of Eastern moles. Giger (1965) found that 87% of juveniles S. townsendii dispersed ,305 m from their birth nests. In a study on Eastern mole home range size, movements and activity patterns, Harvey (1976) remarked one mole undertook an unusually far displacement away from his nest (204 m). We do not report on the effect of forest patch size (in hectares) because this variable had a skewed distribution even after transformation. We used several statistical descriptors to summarize logistic regression model performance (i.e., amount of information lost corrected for small sample size—AICc and DAICc; Akaike, 1974; see review by Burnham and Anderson, 2002), fit (residual deviance) and accuracy (Area Under the receiver operating characteristic Curve, AUC) and the associated model (Mann-Whitney U P-value). AUC measures a model’s ability to discriminate between sites with and without observed mole activity. Values $ 0.7 indicate acceptable discrimination; whereas, those $ 0.8 indicate excellent discrimination (Hosmer and Lemeshow, 2000). We evaluated the distribution of standardized deviance residuals in normal Q-Q plots and use the Cook Statistic to assess whether any sites exerted a disproportionate influence on model prediction. We retain all sites during our analyses of the 2008 survey data, but discuss any sites identified as potential outliers. We determined the amount of unique (or conditional) variance explained by each variable in our global model which included Loam, Local Forest and Dispersal Forest as predictor variables. We did this by subtracting the amount of shared (or confounded) variance explained by each predictor variable from the amount of variance it explained in a univariate context. A variable’s unique variance represents the additional variance it explains after accounting for the variance explained by all other variables (Fletcher and Hutto, 2008). The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:33 64 2010 RITCHIE & NOCERA: EASTERN MOLE DISTRIBUTION 65 We restricted our initial analyses to main effects, but conducted a post hoc assessment of putative interactions for all variables, including Land Class. We used the Southern Ontario Land Resource Information System (2000–2002 release) to classify sites into one of three Land Class categories: Vegetated (e.g., deciduous forests, forests, hedgerows, n 5 19), Built up/Lawns (open and/or grassy areas, n 5 20) and Wetlands (marshes, swamps and shorelines, n 5 9). We did so to assess whether any correlation between Eastern mole occurrence and soil condition or forest cover varies with local land cover. We used the sites with mole sign in either 1997 or 2008 (n 5 23) to assess what site characteristics, if any, were correlated with the change in mole sign distribution between surveys. Sites occupied in 1997 but without mole sign in 2008 were classified as having experienced a change in distribution. Statistical significance was assumed at P # 0.05 when assessing statistical interactions and for change in distribution analyses. Values are reported as Estimate(Standard Error). We conducted our statistical analyses using R v. 2.7.1 (R Development Core Team, 2008). RESULTS Evidence of Eastern mole activity was detected at 37% (17/46) of survey sites in 2008 (Fig. 1), only two of these 17 sites were classified as not having loam or sandy loam (‘‘Loam’’) soils. Among all 46 sites, 29 were classified as having Loam soils, and just over half of those had Eastern mole activity (15/29). No new mole sign was found at sites where none had been detected in 1997, and moles apparently were absent from six sites where their activity previously had been detected. Only one of these sites had Loam soils. We assessed and ranked eight models generated from Loam, Local Forest and Dispersal Forest (Table 1, rlocal-landscape forest 5 0.29). Fairview Cemetery, Cinnamon Fern Environmentally Significant Area (ESA) and Kurtz Farm were identified as sites that exerted a disproportional influence on one or more models. Fairview Cemetery and Cinnamon Fern were both located in areas with Plainfield Sand soils and were the only sites with mole sign not classified as Loam soils. Kurtz Farm had a high proportion of forest cover within 305 m (0.84). We observed no mole sign at this site. Loam occurred in the top four models as ranked by AICc. These models explained the greatest amount of variance (residual variance: 51.04–52.48) and had AUC scores ranging from 0.63 to 0.77 (indicating reasonable discrimination ability). The models best able to discriminate between sites with and without mole sign were those including Loam and forest cover (Loam and Dispersal Forest: AUC 5 0.77; Loam and Local Forest: AUC 5 0.75). The model including only the presence of loam or sandy loam soils had lower discriminatory ability (AUC 5 0.70). Loam uniquely explained 79% of the total variance explained by the global model, whereas Local and Landscape Forest cover accounted for 6% and 5% respectively (Fig. 3). Post hoc assessment of interactions indicated that the effect of landscape forest cover depended on both the site’s land classification and the presence of Loam soils. There was a positive correlation between the amount of landscape forest cover and the presence of mole sign at sites in open grassy areas; we detected no relationship between sites with woody vegetation or located within wetland areas [Built up lawn: 8.33(4.19), P 5 0.05; Fig. 2]. At sites with Loam soils, mole sign was more likely with increasing proportions of landscape forest cover [Loam 5 1: 4.89(2.42), P 5 0.04; Loam 5 0: 22.27(3.33), P 5 0.50]. We did not detect any other two-way interactions (P . 0.05). The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:33 65 66 THE AMERICAN MIDLAND NATURALIST 164(1) TABLE 1.—Logistic regression models describing the distribution of Eastern moles Scalopus aquaticus in southern Ontario based on soil type (Loam, a binary variable: 1 5 Loam, 0 5 Not Loam) and the proportion of forest cover at a local (within home range, 49 m radius, 0.75 ha) and landscape (within dispersal distance, 305 m, 29 ha) scale. Model reporting includes Estimate(SE), model ranking criteria (AICc, unadjusted Mann-Whitney U P-value), measures of fit (residual deviance, Null 5 60.60) and accuracy (area under the receiver operator curve AUC) Model 2.08(0.84) Loam 2 2.01 2.16(0.86) Loam + 1.90(1.88) Dispersal Forest 2 2.45 2.01(0.85) Loam + 0.86(0.94) Local Forest 2 2.25 2.08(0.87) Loam + 0.65(0.98) Local Forest + 1.55(1.97) Dispersal Forest 2 2.54 1.13(0.87) Local Forest 2 0.92 1.45(1.68) Dispersal Forest 2 0.82 1.00(0.91) Local Forest + 0.95(1.76) Dispersal Forest 2 1.06 AICc DAICc Variance df AUC 56.76 58.05 58.21 0.00 1.29 1.45 52.48 51.48 51.64 44 43 43 0.70 0.77 0.75 60.02 63.18 64.13 65.18 3.26 6.42 7.37 8.42 51.04 58.90 59.85 58.61 42 44 44 43 0.76 0.63 0.65 0.63 CHANGE IN DISTRIBUTION (1997–2008) Approximately one quarter (6 of 23) of the sites where mole sign had been reported in 1997 no longer had mole activity. The only predictor of this change in distribution was the presence of loam or sandy loam soils, which was inversely related to the probability of mole sign disappearing from the site. Loam accounted for approximately 2/5 of the variance (10.55, null variance 5 26.40, Px2 , 0.01, AUC 5 0.86, PAUC , 0.01). DISCUSSION Eastern moles were approximately eight times more likely to occur at sites with soils classified as either loam or sandy loams than any other soil type. Evidence of mole activity was no longer detected at 26% of the surveyed sites where moles had been detected a decade prior. We returned to those survey sites with a change in mole distribution with the lead author of the original survey work, G. Waldron, to assess if there was a noticeable change in site conditions. Other than the addition of recreational infrastructure (e.g., stage, maintained lawn, etc.) at one site, no obvious changes were observed. We were unable to reaccess one site due to logistical constraints. In contrast to the disappearance of moles at six sites, mole sign was not found at any survey sites where it had not previously been recorded. Sites with loam or sandy loam soils were more likely to retain signs of mole activity between the 1997 and 2008 sampling periods. However, our study was not designed to determine the mechanism(s) of this correlation. The structure and moisture balance of loam soils may make them easier to dig through, thus allowing a tunnelling mole to conserve energy (Arlton, 1936; Hartman and Yates, 2003). Conversely, moles may not select loams or sandy loams per se, but rather avoid harder and drier soils that are more difficult to tunnel through (Yates and Schmidly, 1978). Evidence of mole activity was absent from all but two sites without Loam soils. It was also absent from approximately half of the survey sites with Loam soils, suggesting that knowledge of a site’s soil texture is important, but insufficient, information to predict mole occurrence. Moles are adapted to a subterranean and energetically expensive lifestyle involving an increased need for heat dissipation while digging extensive tunnel networks (Hartman and Yates, 2003); Habitat selection may also relate to these challenges (e.g., selection of soils with better oxygen availability). Alternatively, variation in prey density such as earthworms, grubs The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:33 66 2010 RITCHIE & NOCERA: EASTERN MOLE DISTRIBUTION 67 FIG. 2.—Interaction between A) open grassy areas/lawns and B) loam or sandy loam soils with the amount of forest cover within the surrounding landscape (305m radius). Sample sizes are indicated above the error bars illustrating the standard error The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:34 67 68 THE AMERICAN MIDLAND NATURALIST 164(1) FIG. 3.—The amount of unique and shared variance explained by each predictor of Eastern mole sign. Values are reported as a percentage of the total variance explained by the global model including soil conditions and the amount of forest cover within a 49 m (Local Forest) and 305 m radius (Dispersal Forest) or ants between Loam and other soil types may affect the distribution of Eastern moles by altering food availability (Arlton, 1936; Brown, 1972; Edwards et al., 1999). The number of sites with loam or sandy loam soil texture lacking mole sign highlights the need to consider other factors affecting Eastern mole distribution. The relationship between forest cover (or a latent covariate) and Eastern mole occurrence appears to vary with scale, soil texture and possibly on the type cover at the site (e.g., vegetated, wetland or lawns). Sites with loam or sandy loam soils were more likely to have mole sign if the surrounding landscape had higher proportions of landscape forest cover. Moles may abandon tunnels for a variety of reasons (e.g., soil desiccation, low food availability, structural disturbance, to undertake natal or breeding dispersal, Arlton, 1936). It is possible that moles are more likely to abandon surface tunnels in areas with little forest cover (Arlton, 1936). Forested areas may serve as core areas from which surface tunnel networks can extend. Moles are prone to deserting or deepening their tunnels during periods of drought and high temperatures (Hisaw, 1923; Arlton, 1936). The shady conditions provided by forests may buffer the rate of moisture and temperature change. Moles apparently can detect and respond to prolonged cool temperatures. This is supported by the fact that moles near wooded areas seem to moult later than those found in treeless areas (Arlton, 1936). We hypothesize that the prolonged retention of soil moisture near wooded areas may allow moles to maintain a larger foraging area during dry periods and to avoid the energy costs of digging new surface tunnels or deepening old ones. The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:37 68 2010 RITCHIE & NOCERA: EASTERN MOLE DISTRIBUTION 69 There are several reasons why mole distribution may more closely coincide with forest cover at a landscape scale than at a local scale. The processes for which forest cover may be the most important could include dispersal or exploratory movements and/or seeking mating opportunities. The most vulnerable life stage for subterranean animals is within the first 6 mo after birth (50% mortality, Hartman, 1995b), likely in part due to increased predator exposure during dispersal (Hartman and Yates, 2003). A subset of juvenile moles may disperse above ground (Leftwich, 1972 in Hartman and Yates, 2003) and moles inhabiting isolated tunnel systems may occasionally visit the surface during the breeding season to find mates (Arlton, 1936). We hypothesize that availability of forest cover during these dispersal movements may decrease the dispersal mortality rate and increase the probability of successful colonization. We also found some support for a positive correlation between the amount of landscape forest cover and the presence of mole sign in open grassy areas. The surface tunnels observed at sparsely vegetated sites (e.g., grassy or bare ground) may have been linked to deeper tunnel networks radiating from forested areas with more stable soil conditions where tunnels are protected from frequent mechanical disturbance. The permanent, deep tunnels of Eastern moles may be preferentially situated under fencerows and serve as major travel corridors (Harvey, 1976). A comparatively low rate of soil disturbance would reduce the need for tunnel repair while protecting nest sites and possible areas of food storage (as seen in Talpa europaea; see Gorman and Stone, 1990, p. 21) from physical disturbance. These areas may serve as a source for dispersing individuals. CONCLUSION We quantitatively assessed the distribution of Eastern moles in relation to loam or sandy loam soils and explored the interaction between Eastern moles and elements of landscape composition. We found that (1) Eastern moles are more likely to occur at sites with loam soil conditions, (2) the species’ continued presence at a site is more likely in the presence of loam and sandy loam soils (3) Eastern moles were more likely to occupy sites with a greater proportion of forest cover within 305 m, an estimated distance over which dispersing moles may travel. Our results suggest that, in addition to being associated with loam and sandy loam soils, moles might do best in a heterogeneous landscape, with forested areas potentially providing long-term stability whereas open areas may provide more efficient foraging grounds. An understanding of the factors influencing the species’ distribution will help provide focus for future scientific research and in supporting population management efforts. Acknowledgments.—We are grateful to Point Pelee National Park (particularly V. McKay and T. Dobbie) and the Essex Regional Conservation Authority for logistical support. G. Waldron provided additional details regarding the 1997 survey. We thank G. Waldron, A. Argue and H. Simpson for assistance in the field. Funding was provided by the Ontario Ministry of Natural Resources (Wildlife Research and Development Sections, Species at Risk Branch and Youth Programs). LITERATURE CITED AKAIKE, H. 1974. A new look at statistical model identification. IEEE T. Automat. Contr., 19:716–723. ARLTON, A. V. 1936. An ecological study of the mole. J. Mammal., 7:349–371. BANFIELD, A. W. F. 1974. The mammals of Canada. University of Toronto Press, Toronto. 33 p. BERTHIER, K., M. GALAN, J. C. FOLTÊTE, N. CHARBONNEL AND J. F. COSSON. 2005. Genetic structure of the cyclic fossorial water vole (Arvicola terrestris): landscape and demographic influences. Mol. Ecol., 14:2861–2871. BROWN, L. N. 1972. Unique features of tunnel systems of the Eastern mole in Florida. J. Mammal., 53:394–395. The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:40 69 70 THE AMERICAN MIDLAND NATURALIST 164(1) BURNHAM, K. P. AND D. R. ANDERSON. 2002. Model selection and multimodel inference: A practical information-theoretic approach. Springer, New York. 488 p. DAVIS, W. B. 1942. Moles (Genus Scalopus) of Texas. Am. Midl. Nat., 27:380–386. DELATTRE, P., R. CLARAC, J. P. MELIS, D. R. J. PLEYDELL AND P. GIRAUDOUX. 2006. How moles contribute to colonization success of water voles in grassland: implications for control. J. Appl. Ecol., 43:353–359. DOBBIE, T., T. MCFADYEN, P. ZORN, J. KEITEL AND M. CARLSON. 2007. Point Pelee National Park: State of the park report 2006. Parks Canada. 44 p. DUHAMEL, R., J.-P. QUÉRÉ, P. DELATTRE AND P. GIRAUDOUX. 2000. Landscape effects on the population dynamics of the fossorial form of the water vole (Arvicola terrestris sherman). Landscape Ecol., 15:89–98. EDWARDS, G. R., M. J. CRAWLEY AND M. S. HEARD. 1999. Factors influencing molehill distribution in grassland: implications for controlling the damage caused by molehills. J. Appl. Ecol., 36:434–442. ESSEX REGION CONSERVATION AUTHORITY (ERCA). 2002a. Report FA 48/02—to the full authority: recalculation of natural areas coverage—Nov. 6, 2002. 3 p. ———. 2002b. Biodiversity Conservation Strategy for Essex Region. FLETCHER JR., R. J. AND R. L. HUTTO. 2008. Partitioning the multi-scale effects of human activity on the occurrence of riparian forest bird. Landscape Ecol., 23:727–739. GIGER, R. D. 1965. Surface activity of moles as indicated by remains in barn owl pellets. Murrelet, 46:32–36. GORMAN, M. L. AND R. D. STONE. 1990. The natural history of moles. Cornell University Press, New York. 138 p. HARTMAN, G. D. AND J. D. KRENZ. 1993. Estimating population density of moles Scalopus aquaticus using assessment lines. Acta Theriologica, 38:305–314. ———. 1995a. Seasonal effects on sex ratios in moles collected by trapping. Am. Midl. Nat., 133:298–303. ———. 1995b. Age determination, age structure, and longevity in the mole, Scalopus aquaticus (Mammalia: Insectivora). J. Zool. (Lond)., 237:107–122. ——— AND T. L. YATES. 2003. Moles: Talpidae, p. 30–55. In: G. A. Feldhamer, B. C. Thompson and J. A. Chapman (eds.). Wild mammals of North America: Biology, management, and conservation. 2nd ed. Johns Hopkins University Press, Baltimore. 1216 p. HARVEY, M. J. 1976. Home range, movements, and diel activity of the Eastern mole, Scalopus aquaticus. Am. Midl. Nat., 95:436–445. HISAW, F. L. 1923. Observations on the burrowing habits of moles (Scalopus aquaticus machrinoides). J. Mammal., 4:79–88. HOFFMAN, D. W., B. C. MATTHEWS AND R. E. WICKLUND. 1964. Soil associations of Southern Ontario. Report No. 30, Ontario Soil Survey. Research Branch, Agriculture Canada and Ontario Agricultural College. 21 p. HOSMER, D. W. AND S. LEMESHOW. 2000. Applied logistic regression. 2nd ed. John Wiley & Sons, Toronto. 375 p. LEE, H. T., W. D. BAKOWSKY, J. RILEY, J. BOWLES, M. PUDDISTER, P. UHLIG AND S. MCMURRAY. 1998. Ecological Land Classification for Southern Ontario: First Approximation and its Application. Ontario Ministry of Natural Resources, Southcentral Science Section, Science Development and Transfer Branch. SCSS Field Guide FG-02. NATURESERVE. 2008. Scalopus aquaticus, In: NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.0. NatureServe, Arlington, Virginia. Available http://www.natureserve. org/explorer. (Accessed: Dec. 1, 2008). NEVO, E. 1979. Adaptive convergence and divergence of subterranean mammals. Annu. Rev. Ecol. Syst., 10:269–308. R DEVELOPMENT CORE TEAM. 2008. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL http://www. R-project.org. The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:40 70 2010 RITCHIE & NOCERA: EASTERN MOLE DISTRIBUTION 71 RICHARDS, N. R., A. G. CALDWELL AND F. F. MORWICK. 1949. Soil survey of Essex County. Ontario Soil Survey, 11. 85 p. ROSENBLATT, D. L., E. J. HESKE, S. L. NELSON, D. M. BARBER, M. A. MILLER AND B. MACALLISTER. 1999. Forest fragments in east- central Illinois: Islands or habitat patches for mammals? Am. Midl. Nat., 141:115–123. ROWE, J. S. 1972. Forest regions of Canada. Department of Environment, Canadian Forestry Service. Publication No. 1300. 172 p. SCHUT, L. W. 1992. The soils of Elgin country. Report No. 63, Ontario Centre for Soil Resource Evaluation. Research Branch, Ministry of Agriculture and Food. 157 p. SOUTHERN ONTARIO LAND RESOURCE INFORMATION SYSTEM. [computer file]. 2002. Ministry of Natural Resources. Peterborough, Ontario. WALDRON, G., L. RODGER, G. MOULAND AND D. LEBEDYK. 2000. Range, habitat, and population size of the Eastern mole, Scalopus aquaticus, in Canada. Can. Field- Nat., 114:351–358. WIENS, J. A. 1989. Spatial scaling in ecology. Funct. Ecol., 3:385–397. YATES, T. L. AND D. J. SCHMIDLY. 1978. Scalopus aquaticus. Mammal. Spec., 105:1–4. SUBMITTED 27 FEBRUARY 2009 ACCEPTED 31 SEPTEMBER 2009 Supplementary Material TABLE S1.—Sites resurveyed for mole sign (surface tunnels and push-ups) in Sep. 2008, including UTM coordinates (Zone 17, NAD83), soil classification, proportion of local forest cover (within an average home-range area, 0.75ha, Local Forest) and forest cover within a dispersal distance (305m, Landscape Forest). E.S.A 5 Environmentally Significant Area, C.A. 5 Conservation Area. A) Sites without mole sign; B) Sites with mole sign. Permission was not granted to resurvey two sites in 2008 X LaSalle Kurtz Farm West Branch of Two Creeks Kennedy Woods, Jack Miner Sanctuary East Mersea Public School 331262 348400 378948 4678639 Berrien Sand 4654800 Bottom Land 4660556 Bottom Land 0 0 0 Vegetated Wetlands Built-up lawns 0.26 0.21 0.25 0.54 0.84 0.09 355529 4658472 Brookston Clay 0 Vegetated 0.59 0.13 376799 0 Built-up lawns 0.00 0.00 Oxley Poison Sumac Swamp E.S.A. Wilson Farm (Rd 2 West) Point Pelee Dr. Fish Point Provincial Nature Reserve Marentette Beach Two Creeks Conservation Area Hillman Marsh Conservation Area 345254 0 Vegetated 0.38 0.44 0 Vegetated 0.00 0.10 371471 360932 4660443 Brookston Clay Sand—Spot Phase 4652590 Caistor Sand—Spot Phase 4657016 Caistor Sand—Spot Phase 4649953 Eastport Sand 4621218 Eastport Sand 0 0 Built-up lawns Vegetated 0.00 0.43 0.00 0.11 376546 379300 4652601 Eastport Sand 4663500 Eroded Channel 0 0 Wetlands Vegetated 0.00 1.00 0.01 0.14 374738 4655492 Marsh 0 Wetlands 0.00 0.00 354284 Y Soil classification Loam Land class Local Landscape forest forest A) Site name The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:40 71 72 THE AMERICAN MIDLAND NATURALIST 164(1) TABLE S1.—Continued A) Site name X Anderson Woods 359360 Wheatley Provincial Park Strathroy Bayview Cemetery Heinz Woods Iler Cemetery Olinda UnitarianUniversalist Cemetery Cedar Creek Conservation Area Ruthven Cemetery Union Water Plant Afflect Woods Lot 10, Concession III Anglican Cemetery Oxley Intalian Park’ (campground) Palen Road Woodlot St Marks Cemetery Rodney Y Soil classification Loam Local Landscape forest forest Land class 0 Vegetated 0.02 0.24 380508 4658341 Parkhill Loam Red Sand—Spot Phase 4660105 Tavistock 0 Vegetated 0.22 0.15 444810 368779 367855 347456 361798 4754892 4654333 4655562 4650990 4660774 0 1 1 1 1 Built-up lawns Built-up lawns Vegetated Built-up lawns Built-up lawns 0.00 0.00 0.53 0.00 0.01 0.03 0.02 0.08 0.00 0.27 348609 4654111 Fox Sandy Loam 1 Wetlands 0.00 0.58 363920 361476 342993 341470 340006 341756 4656525 4655174 4656130 4657575 4650008 4649867 Fox Sandy Loam Fox Sandy Loam Harrow Loam Harrow Loam Harrow Sandy Loam Harrow Sandy Loam 1 1 1 1 1 1 Built-up lawns Built-up lawns Wetlands Wetlands Built-up lawns Built-up lawns 0.00 0.00 1.00 1.00 0.00 0.47 0.17 0.13 0.31 0.17 0.00 0.10 340025 339845 434327 4651272 Harrow Sandy Loam 4652124 Harrow Sandy Loam 4713456 Wattford 1 1 1 Wetlands Vegetated Built-up lawns 1.00 0.44 0.00 0.31 0.03 0.01 Soil classification Loam Local Landscape forest forest B) Site Name X Cinnamon Fern E.S.A. Fairview Cemetery Bennie Woods Klie’s Sugar Bush Sweetfern Woods E.S.A. White Oak Woods E.S.A. Kopegaron Woods C.A. Kingsville Golf and Curling Club Arner Point Conservation Area Evergreen Memorial Cemetery Holy Family Family Retreat House Seacliff Park Union Ravine Mill Creek Ravine 372700 4656500 Plainfield Sand 0 Wetlands 0.80 0.32 378956 369861 346250 372429 4660328 4654132 4653669 4662927 Plainfield Sand Berrien Sandy Loam Berrien Sandy Loam Berrien Sandy Loam 0 1 1 1 Built-up lawns Vegetated Vegetated Vegetated 0.00 0.60 1.00 0.31 0.09 0.17 0.33 0.17 373156 4660598 Berrien Sandy Loam 1 Vegetated 0.34 0.44 376612 1 Wetlands 1.00 0.37 1 Built-up lawns 0.36 0.35 349463 4659463 Brookston Clay Sand—Spot Phase 4655500 Caistor Sand—Spot Phase 4654448 Fox Sandy Loam 1 Vegetated 0.81 0.16 364903 4656206 Fox Sandy Loam 1 Built-up lawns 0.00 0.02 343546 4650408 Fox Sandy Loam 1 Built-up lawns 0.53 0.26 367148 361380 355354 4654584 Fox Sandy Loam 4655210 Fox Sandy Loam 4654801 Harrow Sandy Loam 1 1 1 Vegetated Built-up lawns Built-up lawns 0.00 0.66 0.21 0.00 0.13 0.30 353500 Y Walsingham Berrien Sandy Loam Berrien Sandy Loam Berrien Sandy Loam Burford Loam Land class The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:41 72 RITCHIE & NOCERA: EASTERN MOLE DISTRIBUTION 2010 73 TABLE S1.—Continued B) Site Name X Harrow Park 341301 Harrowood Retirement Community New Settlement Woods E.S.A. 340900 341346 Y Soil classification 4654852 Tuscola Fine Sandy Loam 4654800 Tuscola Fine Sandy Loam 4652523 Tuscola Fine Sandy Loam Loam Land class Local Landscape forest forest 1 Built-up lawns 0.06 0.20 1 Built-up lawns 0.00 0.04 1 Vegetated 0.31 0.40 The American Midland Naturalist amid-164-01-07.3d 20/5/10 11:01:42 73
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