Mammalia 2017; aop Vladimir Dinets* Surface foraging in Scapanus moles DOI 10.1515/mammalia-2016-0091 species that forages underwater, underground and on the Received July 3, 2016; accepted November 29, 2016 surface (Condylura; Nowak 1999, Smith and Xie 2013). Western American moles (Scapanus) are believed Abstract: Some mole genera, including Scapanus of west- to be exclusively underground foragers (Stephens 1906 ern North America, are usually considered to be fully fos- and virtually all subsequent works), although they are sorial. I present data showing that surface foraging is used known to forage under snow in winter in colder parts of by adults of all four Scapanus species, and evidence that their range (Pedersen 1963). Regular occurrence of their such foraging is not a particularly rare behavior. Scapanus remains in owl pellets and among animals killed by moles forage on the surface when leaf litter is wet and domestic cats and dogs (Giger 1965, Maser and Brodie does not produce much noise; they also move slowly, 1966) and by other predators (see Carraway et al. 1993 for remain within a small area, and usually forage in places an overview) is interpreted as evidence of either surface with dense cover. These adaptations decrease the risk of dispersal by juveniles (Giger 1965, Verts and Carraway predation and make surface foraging behavior difficult to 2001) or movement of males seeking females (Naughton detect for human observers. Numerous unpublished and 2012). The former view is supported by the fact that almost a few published observations suggest that many, if not all skulls collected from owl and raptor pellets belong to all, species in other “fully fossorial” mole genera forage juveniles (Pedersen 1963, Giger 1965). Although the pos- on the surface at least occasionally. This is true not just sibility of surface foraging was mentioned by Scheffer for true moles (Talpidae), but also for unrelated, but con- (1949), the only published evidence of such behavior is by vergently similar golden (Chrysotalpidae) and marsupial Dalquest (1948), who reported that a vole killed by a snap (Notoryctidae) moles. Apparently, surface foraging is too trap was consumed by a mole. important for fossorial insectivores to be completely lost Surface foraging by moles is very difficult to detect. even in the most fossorial taxa. They are sensitive to soil vibrations (see Mason and Narins Keywords: behavior; behavioral ecology; fossoriality; 2001 for discussion and bibliography) and light (even Talpidae; true moles. species with eyes covered with skin, see Carmona et al. 2009), and often disappear underground in response to approaching footsteps or flashlight beams (Mellanby 1971, Glösmann et al. 2008). Also, as they do not normally Introduction travel long distances, they are only occasionally caught by pitfall traps. However, in recent years the growing True moles (Talpidae) exhibit a remarkably broad spec- popularity of amateur mammalwatching has resulted in trum of lifestyles. This relatively small family (fewer than slow accumulation of observations of surface foraging of 50 recognized species according to IUCN 2015) includes Scapanus moles. animals with at least six foraging strategies: (1) shrew-like surface foragers (Uropsilus), (2) animals that mostly forage under the leaf litter but also dig burrows and occasion- ally climb shrubs and small trees (Urotrichus, Dymecodon, Neurotrichus, and probably Scaptonyx), (3) those that feed Opportunistic observations predominantly underground but also under the leaf litter The following three reports were provided in response to (Scapanulus, Parascalops, Euroscaptor, and probably Par- my request for such records posted on mammalwatching. ascaptor), (4) “typical” moles that are believed to forage worldpress.com forum. exclusively or almost exclusively underground (Talpa, Venkat Sankar (pers. comm.) observed a broad-footed Mogera, Scalopus, Scapanus and possibly Scaptochirus), mole (Scapanus latimanus) in late February “foraging next (5) aquatic foragers (Desmana, Galemys), and (6) one to a trail one morning after a night of rain near Rancho San Antonio County Park, Cupertino, California. Habitat *Corresponding author: Vladimir Dinets, Psychology Department, was grassy oak woodland with blue oak, coast live oak, University of Tennessee, Knoxville TN 37996, USA, valley oak, and California bay at ~ 500 ft asl. The mole was e-mail: [email protected] an adult.” Brought to you by | UCL - University College London Authenticated Download Date | 1/20/17 10:39 AM 2 V. Dinets: Surface foraging in Scapanus moles William Orr (pers. comm.) “lived in March 2010 in a 4. On 15 January 2002, on a night with dense fog and cabin at the edge of the woods near Forks, Washington, light drizzle, I observed a broad-footed mole foraging with windows at ground level. One warm, rainy night under dense Pacific rhododendron (R. macrophyllum) our entire family watched a mole the size of a rat as it bushes in Kruze Rhododendron State Park, California moved back and forth through leaves and grass outside a (38°35′34″N, 123°19′43″W, 200 m a. s. l.), for ~ 10 min. window, grabbing moths that came to light.” Townsend’s During that time the animal slowly moved in what mole (Scapanus townsendi) is the only mole in the area appeared to be a chaotic pattern within a small area attaining such large size. (less than 1 m2), and consumed a caterpillar (Geom- Joseph K. Green (pers. comm.) observed a broad- etridae) and a small beetle. footed mole near the border of Santa Clara and San Mateo 5. On 2 March 2003, on a foggy night with drizzle and counties, California, “walking midday, along rocky and occasional rain, I found two Mexican moles (S. antho- sandy shore in the riparian woodland of San Francisquito nyi) foraging underneath dense patches of man- Creek”. In this case it is unknown if the animal was forag- zanita (Arctostaphylos sp.) shrubs in the summit ing or moving for other reasons. area of Sierra San Pedro Martyr, Baja Norte, Mexico In hundreds of hours of spotlighting by myself or while (31°02′38″N, 115°27′54″W, 2800 m a. s. l.). Both were guiding mammal-watching tours in appropriate habitats, I seen in pre-dawn hours, ~ 150 m apart. One of the ani- accidentally observed surface foraging by Scapanus moles mals disappeared underground almost immediately, on six occasions, listed below. In all cases the animals whereas the other was observed by me and three tour were first located by barely audible rustling sounds in leaf participants for over 5 min, during which time it con- litter, and approached using red light from a headlamp. sumed a small centipede. The Mexican mole is consid- Although there is no published experimental data on sen- ered to be very rare (Yates and Salazar-Bravo 2005), so sitivity to red light in moles, other subterranean mammals seeing two animals on the same night suggests that are known to be incapable of seeing it (Kott et al. 2010), surface foraging is not rare in this taxon. and mole visual pigments are most sensitive to blue and 6. On 1 May 2016, shortly before midnight on a cool, UV light (Glösmann et al. 2008). I wore soft shoes on all clear night with abundant dew, Steven Linsley and I occasions. observed a coast mole in a forest of Sitka spruce (Picea 1. In June 1999, on a foggy night, I briefly observed a sitkensis) in Humboldt Lagoons State Park, California coast mole (Scapanus orarius) eating an owlet moth (41°12′49″N, 124°06′17″W, 150 m a. s. l.), in an area with caterpillar (Noctuidae) in a thicket of western azalea almost no undergrowth and a layer of dry needles and (Rhododendron occidentale) in Azalea State Reserve, twigs on the ground, within 5 m from the edge of an California (40°55′02″N, 124°04′39″W, 44 m a. s. l.; all extensive western azalea thicket. After a minute of coordinates and altitudes hereafter determined post observing the mole using a red headlamp, I used cam- hoc in Google Earth). The mole disappeared under- era flash to photograph the animal (Figure 1); it imme- ground as soon as I approached it to ~ 2 m. diately began to move faster, produced a few chirping 2. In February 2001, on a night with dense fog and light sounds, and after a few seconds burrowed into the soil. rain, I found a Townsend’s mole foraging under dense shrubs near Lost Man Trail parking lot (41°19′37″N, All observed moles were visually estimated to be within 124°00′55″W, 70 m a. s. l.) in Redwood National adult size ranges for their species (Whitaker 1996, Yates Park, California, at the edge of old-growth forest of and Salazar-Bravo 2005, Reid 2006). In instances when coast redwood (Sequoia sempervirens). The mole was catching and consuming prey was not observed (observa- observed for > 17 min, during which time it moved tions 3 and 6), the behavior was interpreted as foraging ~ 3 m, eventually making almost a full circle, and con- because the animals frequently changed direction and sumed a large worker termite and a small earthworm. probed under fallen leaves and twigs. In two instances 3. In May 2001, on a rainy night, about an hour before of six (observations 1 and 4) the moles were observed in sunrise, I found a broad-footed mole foraging on Rhododendron thickets. Hairy-tailed moles (Parascalops surface of an overgrown flower bed in my garden breweri) of eastern North America also sometimes forage (surrounded by secondary forest of coast redwood) on the surface in such habitats (Dinets 2015), probably in Santa Cruz Mountains, California (37°07′54″N, because dense root tangles make it difficult to dig shallow 121°58′06″W, 400 m a.