Mammalian Presence Surveys Wissahickon Valley Watershed Association Properties, Ambler PA March through December 2015

Transcription

1 Mammalian Presence Surveys Wissahickon Valley Watershed Association Properties, Ambler PA March through December 2015 Alicia N. Shenko, Ph.D. Delaware Valley University, Doylestown PA

2 Table of Contents I. List of Tables.. ii II. List of Figures. ii III. Acknowledgements. iv IV. Impetus for Research V. Methods for Research.. 4 a. Study Area. 5 b. Capture-and-Release Live Trapping. 7 c. Noninvasive Motion Cameras.. 9 d. Noninvasive Hair Collection & Analysis e. WVWA Volunteer Reporting 11 VI. Results of Survey. 12 a. Capture-and-Release Live Trapping. 16 b. Noninvasive Motion Cameras.. 17 c. Noninvasive Hair Collection. 19 VII. Management Recommendations.. 20 VIII. References 24 IX. Appendix A: Maps of Survey Transects. 27 X. Appendix B: Selected Species Accounts XI. Appendix C: Motion Camera Photos 36 Cover photo: Meadow jumping mouse (Zapus hudsonius) at Willow Lake Farm i

3 List of Tables Table 1. Potential list of mammals.. 5 Table 2. List of mammals detected. 15 Table 3. Capture-and-release live trapping data.. 17 Table 4. Noninvasive motion camera data.. 18 List of Figures Figure 1. Map of preserves included in survey Figure 2. Photo of student researchers measuring transect Figure 3. Layout of live traps. 8 Figure 4. Photo of raccoon being weighed. 8 Figure 5. Photo of gray squirrel being marked.. 8 Figure 6. Photo of bait station for noninvasive motion camera. 9 Figure 7. Photo of scent post for noninvasive hair collection 9 Figure 8. Description of hair medulla and cuticle patterns 11 Figure 9. Photos of mammals trapped during survey 16 Figure 10. Photos of hair samples under microscopy 19 ii

4 Acknowledgements I would like to acknowledge Dennis Miranda, Executive Director of the Wissahickon Valley Watershed Association (WVWA), for his initiative in pursuing a study of mammals on WVWA properties to include as part of their overall management strategy and for his exuberance for research on the wildlife of the Wissahickon. John Ferro, Director of Conservation Resources for the WVWA, was instrumental in planning and implementing this research. His vast knowledge of the WVWA properties and understanding of the scientific process were key to accomplishing the goals of this study. I would also like to acknowledge Margaret Rohde, WVWA Naturalist, and the many Trail Stewards and Volunteers of the WVWA for their help in collecting species information and monitoring research sites during the study. In addition, I would like to acknowledge the WVWA for allowing student volunteers from Delaware Valley University (DVU) to gain both research experience and course credit from the wildlife resources available on WVWA properties. The mammalian presence surveys could not have been possible without the tireless work of those student volunteers from DVU, namely Nathaniel Borger, Allison Rusinko, Casey Paholski, Ethan Snyder, Nicole Gann, Alexandra Waldron, and Sarah Oswalt. iii

5 Impetus for Research Conservation of native habitats is a multifaceted endeavor involving the interaction of biotic and abiotic components within the ecosystem. Conducting mammal surveys to establish the community present within an area of interest is an important step in mapping the complete picture of an ecosystem. Given the long-term goals of the Wissahickon Valley Watershed Association (WVWA) to protect and promote both natural lands and wildlife, informed decisionmaking regarding land-use choices is key to increasing success in those areas. It is imperative to add mammalian data to the puzzle of ecosystem functioning within the Wissahickon Watershed. Most notably, the influences of small mammals (mice, voles, and squirrels), mesopredators (raccoon and skunk), and carnivores (fox, coyote, and otter) needs to be understood when creating long-term conservation plans because of their wide-reaching impacts on the ecosystem as a whole. Understanding the complexity of biotic interactions is critical to successful long-term native lands conservation efforts (Ehrenfeld & Toth 1997, Palmer et al. 1997). Mammals comprise multiple trophic levels within naturally-functioning habitats and are responsible for nutrient and energy transfer within the ecosystem (Wike et al. 2000). Mammals are not only a link between trophic levels, but also can be drivers of succession and ecosystem functioning through manipulation of the plant community. Grassland soil health and biodiversity has been linked to digging and burrowing activities of mammals (Martin 2003). Granivorous mammals can disrupt natural fruit-bearing tree seed dispersal cycles by utilizing mesopredator latrines as food sources (LoGiudice & Ostfeld 2002). Seed predators can influence tree recruitment patterns (Schnurr et al. 2004), and seed predation can effect microhabitat conditions and alter tree

6 invasion into old-fields, thereby changing overall plant community structure (Manson & Stiles 1998). Rats are documented to have the ability to change vegetative structure on invaded islands through seed predation and dispersal (Shiels & Drake 2011; Williams et al. 2000). Meadow voles are keystone herbivores in old-field succession, where seedling predation by meadow voles has an effect similar to that of herbivory by ungulates (Howe et al. 2006; Ostfeld & Canham 1993). Meadow voles can also maintain a grassland system and prevent tree invasion in old-fields (Manson et al. 2001, Ostfeld & Canham 1993, Ostfeld et al. 1997, Ostfeld et al. 1999). Habitat alteration and fragmentation can have significant impacts on mammal populations. Mammal diversity and community structure can be used as an indicator of both short-term and long-term anthropogenic disturbance, and mammals can be good bioindicators of habitat quality (Crooks 2002, Leis et al. 2008, Pearce & Venier 2005, Riley et al. 2003, Ruiz- Olmo et al. 1998). Mammal species succession into disturbed areas depends greatly on the vegetative community (Fox & Fox 2000, Monamy & Fox 2010, Richardson 2010, Schweiger et al. 2000). Microhabitat heterogeneity is important in maintaining small mammal community diversity and integral for specialist species to persist in a habitat, and vegetative cover is necessary to maintain mammal communities (Bellows et al. 2001, Fox & Fox 2000, Monamy & Fox 2000, Price et al. 2010, Sauvajot et al. 1998). Complex microhabitats with vertical structure aid in predator avoidance and promote woodland species, and mammals will be more abundant in high quality habitats (Fox & Fox 2000, Kaufman et al. 1993; Morris & MacEachern 2010). Conservation of riparian and forested areas is a pressing concern with the spread of urbanization and increased fragmentation of natural lands. The key to maintaining a balance 2

7 between anthropogenic and natural needs is an understanding of the working mechanisms and interactions of the biotic and abiotic components of these ecological systems. Important components of these ecosystems are mammals, both large and small, whose interactions have been undervalued in many conservation plans. Mammalian species surveys of WVWA properties offer critical information to facilitate the long-term land management goals of the WVWA. 3

8 Methods for Research Mammal studies are unique in that they encompass a large diversity of fauna, from small, insectivorous shrews weighing less than 5g to large, grazing deer weighing well over 75kg. Because of this diversity, the first step in documenting mammals present within an area is to conduct broad-species surveys which assess presence of species (Jones et al. 1996). These surveys provide the basic data required to establish the mammal community within a habitat and provide the information necessary to warrant more specialized techniques in subsequent studies. These sampling methods, however, cannot detect absence of a species. They cannot rule out the presence of a cryptic species that generally requires species-specific methodology, as well as threatened or endangered species that may be present in very low abundance. All work was conducted with the approval of the PA Game Commission (Special Use Permit #34739) and the under the guidance of the Delaware Valley University Institutional Animal Care and Use Committee (Animal Use Approval Form #386-15). The mammalian presence survey targeted a general suite of mammals that could be found on WVWA properties. Capture-and-release live trapping targeted small mammals and mesopredators, while motion cameras and hair collection targeted mesopredators, carnivores, and grazing herbivores. Fossorial animals such as shrews and moles, as well as volant species such as bats were not targeted. These animals require specialized techniques that would not be conducive to a general mammalian presence survey. The list of mammals potentially found on WVWA properties along with species status can be found in Table 1 (Pennsylvania 2015). 4

9 Table 1. List of species potentially found on WVWA properties, Montgomery County PA. List is adapted from the Pennsylvania Mammal Atlas Project and current as of December 2015 (Pennsylvania 2015). Species Common Name (Scientific Name) Status Species Common Name (Scientific Name) Status Carnivores Grazers Eastern coyote (Canis latrans) Common Beaver (Castor canadensis) Common Gray fox (Urocyon cineroargenteus) Unommon in county Muskrat (Ondatra zibethicus) Common Red fox (Vulpes vulpes) Naturalized non-native Groundhog or Woodchuck (Marmota monax) Common River otter (Lontra canadensis) Uncommon in county Eastern cottontail (Sylvilagus floridanus) Common Fisher (Martes pennanti) Uncommon in county White-tailed deer (Odocoileus virginianus) Common Long-tailed weasel (Mustela frenata) Common American mink (Neovison vison) Common Fossorial Domestic cat (Felis catus) Non-native (feral) Northern short-tailed shrew (Blarina brevicauda) Common Domestic dog (Canis lupus familiaris) Non-native (feral) Least shrew (Cryptotis parva) Common Masked shrew (Sorex cinereus) Common Mesopredators Long-tailed shrew (Sorex dispar) Uncommon Virginia opossum (Didelphis virginiana) Common Star-nosed mole (Condylura cristata) Common Striped skunk (Mephitis mephitis) Common Hairy-tailed mole (Parascalops breweri) Common Raccoon (Procyon lotor) Common Eastern mole (Scalopys aquaticus) Common Small Mammals Volant Meadow vole (Microtus pennsylvanicus) Common Big brown bat (Eptesicus fuscus) Common Woodland vole (Microtus pinetorum) Common Eastern red bat (Lasiurus borealis) Common Southern red-backed vole (Myotes gapperi) Common Hoary bat (Lasiurus cinereus) Common White-footed mouse (Peromyscus leucopus) Common Little brown bat (Myotis lucifugus) Common Deer mouse (Peromyscus maniculatus) Common Indiana bat (Myotis sodalis) Federally Endangered Woodland jumping mouse (Napaeozapus insignis) Common Evening bat (Nycticeius humeralis) Uncommon Meadow jumping mouse (Zapus hudsonius) Common Tricolored bat (Perimyotis subflavus) Common Southern flying squirrel (Glaucomys volans) Common Gray squirrel (Sciurus carolinensis) Common Eastern fox squirrel (Sciurus niger) Common Red squirrel (Tamiasciurus hudsonius) Common Eastern chipmunk (Tamias striatus) Common House mouse (Mus musculus) Non-native Norway rat (Rattus norvegicus) Non-native Study Area This study encompasses the major preserves owned by the WVWA, consisting of approximately 331 acres in Whitpain, Lower Gwynned, and Whitemarsh Townships, Montgomery County, Pennsylvania. Overall habitat characteristics of the WVWA properties were documented in the 2013 Natural Resources Inventory (Block et al. 2013). The properties include fragmented upland temperate deciduous forest and riparian forest, as well as open oldfields (maintained with mowing), agricultural lands, and recreational areas. WVWA properties 5

10 are open to public use, including walking/hiking, dog walking, and equestrian trail riding. Trails are maintained throughout the properties by both WVWA staff and volunteers. Eight major preserves were chosen for investigation: Armentrout Preserve, Briar Hill Preserve, Camp Woods, Crossways Preserve, Four Mills Nature Preserve, Penllyn Natural Area, Timoney Preserve, and Willow Lake Farm. Each preserve was designated as a single survey unit. Due to the significant habitat differences at Crossways Preserve, the forested areas and open field areas were considered separate survey units (Figure 1). Individual survey transects can be found in Appendix A. Figure 1. Map of the WVWA preserves included within the mammalian presence survey. 6

11 Each survey unit was assessed for a minimum of two weeks between the months of May and December 2015 to document presence of small mammals, mesopredators, and carnivores. Labor was performed both by faculty of Delaware Valley University (DVU), undergraduate students enrolled in DVU s e360 Experiential Learning Program, and undergraduate student volunteers (Figure 2). Figure 2. DVU students placing transect line for capture-andrelease live trapping at Willow Lake Farm. Left-to-right: Allison Rusinko, Casey Paholski, Nicole Gann. Capture-and-Release Live Trapping Small mammals and mesopredators were assessed via capture-and-release live trapping. Trapping transect lines of 400m were established within each survey unit that consisted of 180 mixed size box traps placed in arrays every 20m. Each array consisted of 9 traps: 2 small Sherman SFA-P box traps, 4 medium Sherman LFA-P box traps, 2 large Tomahawk box traps, and 1 extra-large Tomahawk 207 box trap (Figure 3). Traps were in place for a week-long conditioning period in which no trapping occurred, then trapped for 3 consecutive nights. This allowed for approximately 540 trap-nights per survey unit, needed to properly conduct a species diversity survey of the area (Jones et al. 1996). Small, medium, and large traps were baited with a commercial mixture of bird seed while extra-large traps were baited with commercial cat food and strawberries. Animals were marked with non-permanent paint to avoid recounting during the trapping period. Each individual was identified to species, aged, weighed, and sexed when possible (Figures 4 and 5). 7

12 Figure 3. Layout of capture-and-release live traps along each trapping transect. Actual arrangement within each trap set was randomized and related to available habitat characteristics. Figure 4. Photograph of a DVU student weighing a raccoon captured in an extra-large live trap at Four Mills Nature Preserve. Figure 5. Photograph of a DVU student marking a gray squirrel with orange nontoxic paint at Timoney Preserve. 8

13 Noninvasive Motion Cameras Carnivores and mesopredators were assessed via noninvasive camera-trapping. Reconyx HC600 motion cameras were placed within each survey unit for a period of at least two weeks. They were positioned away from trapping transects to minimize prey interactions and away from recreational and residential areas in order to minimize interaction with the public. Camera trapping was conducted at all survey sites except for Penllyn Natural Area due to the abundance of human activity in the area. Cameras were baited with deer carcasses (when available), as well as chicken, fruit, canned sardines, and whole fish to target a wide range of species including the potential to attract otters (Figure 6) (Kays & Slauson 2008, O Connell Jr. et al. 2006, Schlexer 2008). Mammals attracted to the bait stations were photographed in 5-photo sets, with 3 seconds between photos. Animals were then identified to species. Figure 6. Bait for a motion camera used for noninvasive camera trapping at Timoney Preserve. Station is baited whole tilapia (nailed to tree), canned sardine (buried), chicken legs (nailed to tree), and strawberries (container staked to ground). Figure 7. Scent post affixed with carpeting and wrapped with barbed wire for hair collection at Crossways Preserve. 9

14 Noninvasive Hair Collection & Analysis Hair collection devices were deployed to attempt to document species that could avoid detection otherwise and are a widely-used technique to encourage visitation by a wide variety of species (Kendall & McKelvey 2008). Devices were positioned away from trapping transects to minimize prey interactions and away from recreational and residential areas in order to minimize interaction with the public. Four different types of devices were used from August to December 2015: carpet pads, scent posts, hair cubbies, and hair corrals. Carpet pads, scent posts, and cubbies were baited with castor lure and fox gland lure obtained from a local recreational trapper. The hair corral was baited with a deer carcass obtained from the PA Game Commission. Carpet pads consisted of commercial-grade outdoor carpeting with lumber nails protruding from them. Bait would elicit rubbing behavior on the pad and allow hair samples to be gathered. There were 5 carpet pads deployed at Crossways Preserve, 4 at Briar Hill Preserve, and 5 at Willow Lake Farm. Scent posts were wooden fence posts affixed with carpeting and wrapped with barbed wire (Figure 7). There were 5 posts placed at Crossways Preserve, 5 posts at Briar Hill Preserve, 5 posts at Willow Lake Farm, and 3 posts at Armentrout Preserve. Hair cubbies consisted of wooden boxes (75cm x 25cm) threaded with barbed wire and metal wire brushes hair collection devices. One cubby was deployed at Timoney Preseve and another at Crossways Preserve. A hair corral was simply barbed wire wrapped tightly around trees encircling an area approximately 4m 2. The deer carcass was placed in the center of the corral. Due to the potential danger of these devices and the widespread use of WVWA lands, only one was used at the Timoney Preserve. 10

15 Hair collected from scent posts was identified to species using reference comparison, scale pattern, and medullary characteristics (Figure 8) (O Connell Jr. et al. 2006). Microscopy was focused on medulla and cuticle attributes specific to species. Comparisons were made using a reference collection of slides from the DVU mammal collection as well as to other published sources of medullary and cuticle patterns for species (Debelica & Theis 2009, Nickoloff 2013). Figure 8. Medulla and cuticle characteristics used in hair identification (after Debelica & Theis 2009). WVWA Volunteer Reporting General species presence/absence was also surveyed via track identification through the WVWA volunteer program. Volunteers were trained on track photography techniques during a one-day WVWA volunteer training session and a photography ruler was provided (Fisher Scientific S40641). Volunteers were then asked to record tracks encountered during the course of normal volunteer activities. Volunteers were asked to a track report consisting of the track description, photograph, and location found to John Ferro. No photos taken during the survey were submitted. 11

16 Results of Survey The mammalian presence survey of WVWA properties produced a suite of species commonly known to occur in Montgomery County, PA. Table 2 summarizes the total species found during the survey, which survey areas in which they were detected and the method with which they were detected. Many of these species are known to occur in the area, but documenting their presence on WVWA properties is important step in the natural resource management of the properties. Five species of carnivores were detected on WVWA properties: the eastern coyote, red fox, American mink, domestic cat, and domestic dog. The eastern coyote is known to inhabit wooded areas near urban zones because of the availability of food sources, but its documentation within WVWA properties demonstrates the potential for these preserves to be important refugia for biodiversity within the region. The presence of domestic cats was significantly less than expected given the proximity of homes and tendency for such parks and preserves to become colonized by feral cats. While researchers expected to encounter domestic cats frequently during early morning hours, observations of feral or outdoor cats was limited to one deceased animal at Briar Hill Preserve and hair collected at Timoney Preserve. Documentation of domestic dogs was expected at WVWA properties and data was only noted if the animal was recorded as part of the survey, not if the animal was encountered recreationally. All individuals recorded during the survey were believed to be off-leash pets, not feral, free-roaming dogs. Two species of mesopredators were recorded, the raccoon and the striped skunk. The raccoon was recorded at almost all preserves surveyed and was most likely present but undetected at Penllyn Natural Area. Due to the public, highly-visible nature of this preserve, extra-large live traps and motion cameras were not used. The striped skunk was only observed at one site, and the Virginia opossum was undetected; both species are believed to be common in 12

17 the area. Live trapping and motion cameras were baited appropriately to detect the species, but it is unknown why they were not detected with regularity. Seven species of small mammals were documented during the survey, selected species accounts are located in Appendix B. They include: the meadow vole, white-footed mouse, meadow jumping mouse, house mouse, gray squirrel, chipmunk, and southern flying squirrel. One gray squirrel was also noted on a motion camera. The capture of a southern flying squirrel in a ground-based trap is unusual, and indicates that this species is likely found in abundance at Briar Hill Preserve. Usually, this species requires targeted methods utilizing arboreal traps. The small mammals documented during this survey were consistently found within their typical microhabitat preferences, demonstrating the biological value of maintaining heterogeneous habitats within the preserves. Most of small mammals serve an ecological role as prey species for birds of prey and large carnivores; they are also known to disperse seeds, predate upon insects, and impact tree seedling survivorship. Because of their multiple roles in maintaining ecosystem health and function, they can be thought of as an important indicator group for the complexity of an area s bio-functioning. It is important to note that only one non-native house mouse was captured during the survey, at Willow Lake Farm. Given the proximity of residential and commercial properties to many of these locations, it was surprising to not encounter non-native species more often. Non-native species thrive in degraded habitats, indicating that the WVWA preserves do maintain ecological integrity in their functioning. Three species of grazers were encountered during the survey: the groundhog (woodchuck), eastern cottontail, and white-tailed deer. Given the common nature of these species and there general habitat preference for any open, grassy area, they are likely to occur on all WVWA properties even though they were not detected on some. Beaver and muskrat were 13

18 not detected during the survey, but have a historic range along the Wissahickon watershed. Muskrat prefer still, impounded water and trapping did not occur specifically along any ponds, lakes, or their embankments. Beaver was reported to the research team to be building a dam upstream of Four Mills Nature Preserve in January 2016 by Margaret Rhode. Fossorial and volant species were not targeted during this general presence survey because of the specialized techniques required to properly assess the groups. However, shorttailed shrews were detected at Crossways Preserve within a live-trap and Camp Woods incidentally along a trail. Finding expired individuals along trails is not uncommon, as they expire from natural causes frequently and can be dropped after capture by a bird of prey. Trail volunteers had reported many past sighting of shrews along trails, but none specifically during the course of the survey. Margaret Rhode also reported a masked shrew along a trail in March of

19 Table 2. A summary of species present on WVWA properties, Montgomery County PA, the properties they were found on, and the method by which they were detected. Species Detected Properties Occurring Method of Detection Carnivores Coyote Timoney, Preserve, Willow Lake Farm Motion camera Red fox Armentrout Preserve, Camp Woods, Crossways Preserve, Timoney Preserve, Willow Lake Farm Motion camera American mink Timoney Preserve Hair collection Domestic cat Briar Hill Preserve, Timoney Preserve Hair collection Observation Domestic dog Crossways Preserve, Timoney Preserve Motion camera Hair collection Mesopredators Raccoon Armentrout Preserve, Briar Hill Preserve, Camp Woods, Crossways Preserve, Four Mills Nature Preserve, Timoney Preserve, Willow Lake Farm Live trapping Motion camera Striped skunk Timoney Preserve Observation Small mammals Meadow vole White-footed mouse Meadow jumping mouse Armentrout Preserve, Briar Hill Preserve, Crossways Preserve (meadow), Timoney Preserve Briar Hill Preserve, Camp Woods, Crossways Preserve (forest), Four Mills Nature Preserve, Penllyn Natural Area, Timoney Preserve, Willow Lake Farm Armentrout Preserve, Briar Hill Preserve, Willow Lake Farm Live trapping Live trapping Live trapping House mouse Willow Lake Farm Live trapping Gray squirrel Chipmunk Briar Hill Preserve, Crossways Preserve, Four Mills Nature Preserve, Timoney Preserve, Willow Lake Farm Briar Hill Preserve, Camp Woods, Four Mills Nature Preserve, Willow Lake Farm Live trapping Motion camera Live trapping Observation Southern flying squirrel Briar Hill Preserve Live trapping Grazers Groundhog (woodchuck) Eastern Cottontail White-tailed deer Armentrout Preserve, Briar Hill Preserve, Crossways Preserve, Timoney Preserve Armentrout Preserve, Briar Hill Preserve, Camp Woods, Crossways Preserve, Willow Lake Farm Armentrout Preserve, Briar Hill Preserve, Camp Woods, Crossways Preserve, Four Mills Nature Preserve, Penllyn Natural Area, Timoney Preserve, Willow Lake Farm Observation Observation Motion camera Observation Fossorial Short-tailed shrew Crossways Preserve (meadow), Camp Woods Live trapping Observation 15

20 Capture-and-Release Live Trapping Capture-and-release live trapping was performed at all survey units. Crossways Preserve was divided into forest and meadow sections to better represent the dichotomous habitats at that site. Extra-large traps were not utilized at Penllyn Natural Area because of the open habitat and frequency of public use. Nine species were detected using capture-and-release live trapping: raccoon, meadow vole, white-footed mouse, meadow jumping mouse, house mouse, gray squirrel, chipmunk, southern flying squirrel, and short-tail shrew (Figure 9). Table 3 highlights the specific capture numbers at sites and represents number of individuals detected and does not count recaptured animals. Overall trapping effort produced 167 mammals: 10 raccoons, 88 meadow voles, 14 white-footed mice, 12 meadow jumping mice, 1 house mouse, 31 gray squirrels, 9 chipmunks, 1 southern flying squirrel, and 1 short-tailed shrew. Figure 9. Photos of mammals trapped during the WVWA mammalian presence survey. Top left: gray squirrel, Willow Lake Farm. Top middle: raccoon, Timoney Preserve. Top right: chipmunk, Camp Woods. Bottom left: meadow vole, Timoney Preserve. Bottom middle: meadow jumping mouse, Willow Lake Farm. Bottom right: southern flying squirrel, Briar Hill Preserve. 16

21 Table 3. Data for all individuals captured during the mammalian presence survey of WVWA properties, Montgomery County, PA. Numbers represent individuals captured, not including recaptured animals. Raccoon Meadow vole Whitefooted mouse Meadow jumping mouse House mouse Gray squirrel Chipmunk Southern flying squirrel Shorttailed shrew Armentrout Preserve Briar Hill Preserve Camp Woods Crossways Preserve (forest) Crossways Preserve (meadow) Four Mills Nature Preserve Penllyn Natural Area Timoney Preserve Willow Lake Farm Total individuals Noninvasive Motion Cameras Camera-trapping occurred at all survey areas, with the exception of Penllyn Natural Area. Cameras were not deployed at Penllyn Natural Area due to security concerns with the frequency of public use and inability to be discreet in the open habitat. Deer carcasses were used as camera bait when they became available from Montgomery County road patrol and PA Game Commission; otherwise, a mixture of chicken, whole fish, canned sardines, and strawberries was used to attract animals to the motion area of the cameras. Table 4 describes the motion camera data from each preserve. Species recorded on motion cameras were: white-tailed deer, raccoon, 17

22 red fox, coyote, domestic dogs (off-leash pets), and a gray squirrel. Full-page motion camera photos can be found in Appendix C. Coyotes were only detected when using a deer carcass as bait which may indicate the need for a larger food item to draw that species. It is unknown whether coyote were drawn to mixed bait, but not close enough to trigger the motion camera. In addition to mammals, turkey vultures (Cathartes aura), black vultures (Coragyps atratus), and red-tailed hawks (Buteo jamaicensis) were also detected on motion cameras. Table 4. Noninvasive motion camera data from the mammalian presence survey of WVWA properties, Montgomery County PA. Dates given indicate the time frame that a camera was deployed at the preserve. Dates Photos Bait Species Armentrout Preserve 7/12/15 to 7/16/ Mix White-tailed deer Raccoon 10/11/15 to 10/28/ Deer Briar Hill Preserve 9/8/15 to 9/29/ Mix 9/4/15 to 9/28/ Mix Camp Woods 6/26/15 to 7/22/ Mix Crossways Preserve 6/4/15 to 6/24/ Deer Four Mills Nature Preserve 6/17/15 to 7/8/ Mix Timoney Preserve 7/29/15 to 8/5/ Mix 10/1/15 to 10/20/ Deer Willow Lake Farm 6/3/15 to 6/10/ Deer White-tailed deer Red fox White-tailed deer Raccoon Gray squirrel White-tailed deer Raccoon White-tailed deer Raccoon Red fox White-tailed deer Raccoon Red fox Domestic dog White-tailed deer Raccoon White-tailed deer Red fox Domestic dog White-tailed deer Red fox Coyote White-tailed deer Red fox Coyote 18

23 Noninvasive Hair Collection Hair collection only produced results at the hair corral placed within Timoney Preserve. Four samples were collected and later identified through comparison of medullary and cuticle patterns from the reference collection at DVU. Species detected were American mink (2 samples), domestic cat, and domestic dog (Figure 10). While hair sampling is a popular, traditional method to detect both common and cryptic species, it was not overly productive during deployment at WVWA properties. This is most likely due to insufficient sampling or individual animal reluctance to rub, as lures used have been highly successful in the past. Motion cameras placed at Briar Hill Preserve included a view of the scent posts in use and show that both raccoons and white-tailed deer approached the posts but did not rub. Even though few samples were collected, hair collection was the only method of sampling to detect American mink on WVWA properties. This is a very important finding, demonstrating that American mink are active within Timoney Preserve and likely utilize other WVWA properties through habitat corridors between preserves. It also confirms sightings made by volunteers in the past of American mink along the Green Ribbon Trail and as road kill, indicating a sustained population of the species within WVWA properties. Figure 10. Photos of hair samples collected at Timoney Preserve showing medullary characters under microscopy. From left: American mink, domestic cat, domestic dog. 19

24 Management Recommendations The mammalian presence survey of WVWA properties detected a suite of species known to occur in the area, including both native and non-native species. The species detected are common but demonstrate that the preserves harbor biodiversity in an increasingly urban environment. Continued stewardship and management of the land will ensure that ecosystem functioning endures. Without habitat areas like the WVWA preserves as refugia, many of these mammals would not persist within residential or commercial developments. Carnivores like coyote and red fox are known to frequent developed areas for access to food, but need forested or rural land to den. They are commonly found now on the edges of developed zones and can thrive in areas like WVWA preserves. American mink does not tolerate development as well as other species of carnivore and is typically more restricted to using forested lands. Allowing the habitat to undergo natural changes and maintaining some of those changes is important for sustaining habitat for carnivores; they require dead standing wood and tree falls for both hunting cover and den areas. Domestic cats were detected at Briar Hill Preserve and Timoney Preserve; both feral and owned-outdoor domestic cats pose a significant risk to native wildlife and are thought to be the single-most cause of mortality to wildlife in the United States (Loss et al. 2013). Many parks and preserves near development become overrun with domestic cats as a product of intact ownedoutdoor individuals, owner dumping, ineffective trap-neuter-release practices, and feral colony supplementation with food and shelter. Domestic cats were not observed in high abundance and effort should be made to ensure significant populations are not established at the WVWA preserves. It is known that native species of small mammals like white-footed mice, meadow jumping mice, and southern flying squirrel do not thrive in developed areas, and are generally 20

25 replaced with the non-native house mouse and Norway rat or the more generalist species like gray squirrels. Other species of mammals documented on WVWA properties have a broader habitat requirement and can tolerate more development, but natural habitat areas promote natural behaviors and population levels. Most small mammals have strongly partitioned niches within the habitat, some like the meadow jumping mouse and meadow vole requiring wet open fields and others like the white-footed mouse and southern flying squirrel requiring hard-masting upland forest. Maintenance of a heterogeneous habitat in multiple stages of succession within the WVWA preserves is key to maintaining a rich community of mammals. Grazers were documented at every survey site, not uncommon for these species. While eastern cottontails do not pose significant risk to the habitat, both groundhogs (woodchucks) and white-tailed deer require active management to keep populations within acceptable anthropogenic levels. Groundhogs and muskrat (undetected) can damage water maintenance structures and natural embankments during burrowing activities when populations are high. Groundhogs can also create walking hazards for the public. White-tailed deer are actively managed in Montgomery County by the PA Game Commission and efforts should be made to maintain healthy levels of white-tailed deer on WVWA properties in cooperation with local PA Game Commission population levels. Allowing the controlled management of white-tailed deer on WVWA properties benefits all species within the ecosystem, most notably growth of native herbaceous vegetation. Native vegetation is important to whole ecosystem functioning in provided both food and cover for all members of the ecosystem, including mammals. The public use of WVWA properties is crucial to the mission of the WVWA and should continue on the preserves. The educational, recreational, and aesthetic value of the preserves are important resources to the community, and the presence of people in the preserve should be 21

26 guided in a way that promotes ecological integrity of the land. Trails are maintained at varying widths in different preserves, but wide trails can be seen as barriers to movement by many small mammals. Care should be taken to maintain trails to a minimum required width for recreational use. The presence of equestrian activity on the preserves is significant and can degrade walking trails, facilitating the need for wider trails or additional trails, fragmenting the habitat. Care should be made to limit equestrian activity on wet ground when damage to trails is highest. Additionally, the presence of off-leash domestic dogs within the preserves was noted in very high frequency. While notices are posted, many visitors to the preserves do not comply. Even with special notices posted during the survey and the verbal communication by researchers to individuals encountered during the survey, dogs were repeatedly seen off-leash. This poses a significant risk to wildlife, domestic dogs, and community members. Encounters between domestic dogs and wildlife cannot be controlled when a dog is off-leash, and more still when the dog is out of the owner s sight. Risk of injury or death to wildlife or dogs is possible, and possibility of disease transmission is also likely. Public relations and possibly legal liability are at risk if such incidences occur. Given the data collected during the general mammalian presence survey of WVWA properties, the following recommendations are made: 1. Active management of all preserves to restore native habitats and maintain habitat heterogeneity by reducing invasive vegetation, limiting removal of tree falls and dead standing trees, and continuing mechanical maintenance of open grasslands. 2. Continued periodic monitoring of mammal populations on WVWA properties through noninvasive techniques and monitoring of small mammals through capture-and-release live trapping on a multi-annual rotation. 22

27 3. Specialized surveys to assess populations of mammals not targeted during this general presence survey, especially volant species (bats) due to their significant population declines throughout Pennsylvania. The federally endangered Indiana bat has had historic populations in neighboring counties. 4. Reduction of trail width and trail abundance to reduce habitat fragmentation and barriers to movement of wildlife, and reduction of equestrian activities when trail damage is likely. 5. Enforcement of off-leash dog policies to reduce potential conflicts and disease transmission with wildlife. 6. Active monitoring and removal of feral domestic cats from WVWA properties. 23

28 References Bellows, A. S., J. F. Pagels, and J. C. Mitchell Macrohabitat and Microhabitat Affinities of Small Mammals in a Fragmented Landscape on the Upper Coastal Plain of Virginia. The American Midland Naturalist 146: Block, T.A., A.F. Rhoads, and C. Skema Technical report: Natural Resources Inventory of Wissahickon Valley Watershed Association Preserves and the Green Ribbon Trail. Botany Department, Morris Arboretum of the University of Pennsylvania. 111p. Crooks, K.J Relative Sensitivities of Mammalian Carnivores to Habitat Fragmentation. Conservation Biology 16: Debelica, A. and M. L. Thies Atlas and Key to the Hair of Terrestrial Texas Mammals. Special Publication No. 55, Museum of Texas Tech University. 108p. Dolan, P.G. and D.C. Carter Glaucomys volans. Mammalian Species 78: 1-6. Ehrenfeld, J. G., and L. A. Toth Restoration ecology and the ecosystem perspective. Restoration Ecology 5: Fox, B.J. and M.D. Fox Factors Determining Mammal Species Richness on Habitat Islands and Isolates: Habitat Diversity, Disturbance, Species Interactions and Guild Assembly Rules. Global Ecology and Biogeography 9; Howe, H. F., B. Zorn-Arnold, A. Sullivan, and J. S. Brown Massive and distinctive effects of meadow voles on grassland vegetation. Ecology 87: Jones, C., W.J. McShea, M.J. Conroy, and T. H. Kunz Capturing Mammals. Pages in D.E. Wilson, F. R. Cole, J.D. Nichols, R. Rudran, and M.S. Foster, editors. Measuring and Monitoring Biological Diversity: Standard Methods for Mammals. Smithsonian Institute Press: Washington. Kays, R.W. and K.M. Slauson Remote Cameras. Pages in R.A. Long, P. MacKay, W.J. Zielinski, J.C. Ray editors. Noninvasive Survey Methods for Carnivores. Island Press: Washington, D.C. Kaufman, D. W., S. K. Peterson, R. Fristik, and G. A. Kaufman Effect of Microhabitat Features on Habitat Use by Peromyscus leucopus. American Midland Naturalist 110: Kendall, K.C. and K.S. McKelvey Hair Collection. Pages in R.A. Long, P. MacKay, W.J. Zielinski, J.C. Ray editors. Noninvasive Survey Methods for Carnivores. Island Press: Washington, D.C. Lackey, J.A., D.G. Huckaby, and B.G. Ormiston Peromyscus leucopus. Mammalian Species 247:

29 LoGiudice, K., and R. S. Ostfeld Interactions between mammals and trees: predation on mammal-dispersed seeds and the effect of ambient food. Oecologia 130: Loss, S.R., T. Will, and P.P. Marra The impact of free-ranging domestic cats on wildlife of the United States. Nature Communications 4: 1-8. Manson, R. H., and E. W. Stiles Links between microhabitat preferences and seed predation by small mammals in oldfields. Oikos 82: Manson, R. H., R. S. Ostfeld, and C. D. Canham Long-term effects of rodent herbivores on tree invasion dynamics along forest-field edges. Ecology 82: Martin, G The role of small ground-foraging mammals in topsoil health and biodiversity: Implications to management and restoration. Ecological Management & Restoration 4: Monamy, V., and B. J. Fox Responses of two species of heathland rodents to habitat manipulation: vegetation density thresholds and the habitat accommodation model. Austral Ecology 35: Morris, D. W., and J. T. MacEachern Active density-dependent habitat selection in a controlled population of small mammals. Ecology 91: Nickoloff, A.L Key and Atlas to the Hair of Terrestrial Pennsylvania Mammals. PhD Thesis. The Pennsylvania State University. O Connell Jr., A.F., N.W. Neil, W. Talency, L.L. Bailey, J.R. Sauer, R. Cook, and A.T. Gilbert Estimating Site Occupancy and Detection Probability Parameters for Meso- and Large Mammals in a Coastal Ecosystem. The Journal of Wildlife Management 70: Ostfeld, R. S., and C. D. Canham Effects of meadow vole population density on tree seedling survival in old fields. Ecology 74: Ostfeld, R. S., R. H. Manson, and C. D. Canham Effects of rodents on survival of tree seeds and seedlings invading old fields. Ecology 78: Ostfeld, R. S., R. H. Manson, and C. D. Canham Interactions between meadow voles and white-footed mice at forest-oldfield edges: competition and net effects on tree invasion of oldfields. Pages in G. W. Barrett, and J. D. Peles, editors. Landscape Ecology of Small Mammals. Springer-Verlag New York, Inc., New York. Palmer, M. A., R. F. Ambrose, and N. L. Poff Ecological theory and community restoration ecology. Restoration Ecology 5: Pearce, J., and L. Venier Small mammals as bioindicators of sustainable boreal forest management. Forest Ecology and Management 208:

30 Pennsylvania Mammal Atlas Wild Mammal List Pennsylvania Mammal Atlas Project. Accessed 11 March Price, B., A. S. Kutt, and C. A. McAlpine The importance of fine-scale savanna heterogeneity for reptiles and small mammals. Biological Conservation 143: Reich, L.M Microtus pennsylvanicus. Mammalian Species 159: 1-8. Richardson, M. L Effects of grassland succession on communities of small mammals in Illinois, USA. Biologia 65: Riley, S.P.D., R.M. Sauvajot, T.K. Fuller, E.C. York, D.A. Kamradt, C. Bromley, and R.K. Wayne Effects of Urbanization and Habitat Fragmentation on Bobcats and Coyotes in Southern California. Conservation Biology 17: Ruiz-Olmo, J., A. Calvo, S. Palazón, and V. Arqued Is the Otter a Bioindicator? Galemys 10: Sauvajot, R. M., M. Buechner, D. A. Kamradt, and C. M. Schonewald Patterns of human disturbance and response by small mammals and birds in chaparral near urban development. Urban Ecosystems 2: Schlexer, F.V Attracting Animals to Detection Devices. Pages in R.A. Long, P. MacKay, W.J. Zielinski, J.C. Ray editors. Noninvasive Survey Methods for Carnivores. Island Press: Washington, D.C. Schnurr, J. L., C. D. Canham, R. S. Ostfeld, and R. S. Inouye Neighborhood analyses of small-mammal dynamics: Impacts on seed predation and seedling establishment. Ecology 85: Schweiger, E. W., J. E. Diffendorfer, R. D. Holt, R. Pierotti, and M. S. Gaines The interaction of habitat fragmentation plant, and small mammal succession in an old field. Ecological Monographs 70: Shiels, A. B., and D. R. Drake Are introduced rats (Rattus rattus) both seed predators and dispersers in Hawaii? Biological Invasions 13: Wike, L. D., F. D. Martin, H. G. Hanlin, and L. S. Paddock Small mammal populations in a restored stream corridor. Ecological Engineering 15, Supplement 1:S121-S129. Williams, P. A., B. J. Karl, P. Bannister, and W. G. Lee Small mammals as potential seed dispersers in New Zealand. Austral Ecology 25: Whitaker Jr., J.O Zapus hudsonius. Mammalian Species 11:

31 Appendix A: Maps of Survey Transects 27

32 28

33 29

34 30

35 Appendix B: Selected Species Accounts 31

36 Meadow Vole Meadow voles are from the family Cricetidae and typically live in moist grasslands and woodlands. They have the largest range of any American Microtus, naturally occurring throughout Canada, the north and east United States, and into Mexico. Meadow voles are typically found in wet grasslands, along streams, and along agricultural fields. They can be seen as agricultural pests when populations are high. Meadow voles are large, with a body length of cm, tail of cm, and weighing g. They have a brown dorsal pelage, with individual hairs in tri-colored bands of dark grey, orange, and dark brown, and a dark grey ventral pelage. Meadow voles can live for 10 to 16 months and are solitary animals that act aggressively upon encountering each other. The only exception to this is male-female encounters during mating. Individuals can keep a home range between 0.10 ha and 0.86 ha. Meadow voles are primarily herbivorous, feeding on available grasses, sedges, and herbaceous plants, but sometimes feed on insects or scavenge animal remains. They are prey for hawks, owls, snakes, and other carnivores (Reich 1981). 32

37 White-footed Mouse White-footed mice are members of the family Cricetidae and are typically found in forests, shrub areas, and dry grasslands. They range through the eastern United States, as far north as southern Alberta and south throughout Caribbean Central America, but the species is absent from Florida. White-footed mice are cm in body length, with a cm tail, and weigh g. They are brownish-gray in color, with a dark brown dorsal stripe often apparent, but juveniles are distinctly gray with no stripe. Ventral pelage is a bright white regardless of age. White-footed mice usually have annual population turnovers, and population size is thought to be density dependent. They are social, and can have overlapping home range areas of approximately 0.1 ha. White-footed mice are semi-arboreal and omnivorous, feeding on insects, seeds, and vegetation. They are common prey for a variety of avian, reptilian, and mammalian carnivores (Lackey et al. 1985). 33

38 Meadow Jumping Mouse Meadow jumping mice are from the family Zapodidae and are typically found in wet grasslands, shrub fields, and wet wooded areas with dense ground cover. They range throughout Canada and the eastern United States, west to Wyoming and south to Arkansas and northern Georgia. Meadow jumping mice have a body length of 8-10 cm, tail length of cm, hind foot of 3-4 cm, and weigh g. They have a yellow-brown dorsal pelage with dark brown dorsal stripe that runs the length of the body, a white ventral pelage, and a distinctly bicolor tail. The extremely long tail and large hind feet of meadow jumping mice are characteristic in identifying this species. Unlike most other small mammals, meadow jumping mice hibernate during the winter months. Meadow jumping mice do not show intraspecies aggression and often hibernate in small groups. They maintain a home range of ha, with males usually having a larger home range than females. Meadow jumping mice feed primarily on seeds and berries, but nuts and insects have been found in their diet. They are prey for a variety of carnivores including hawks and owls (Whitaker 1972). 34

39 Southern Flying Squirrel Southern flying squirrels are from the family Sciuridae and typically live in hardwood forests with large mast-producing trees. They have a large from southern Quebec through the eastern United States, and sporadically in mountainous regions of Central America. Southern flying squirrels are gliders and have loose skin connecting forelimbs to hind limbs (patagium), a body length of cm, tail of 8-12 cm, and weighing g. They have a grayish-brown dorsal pelage and a light brown to white ventral pelage, patagium is bordered with dark brown to black fur. Cheeks and forefeet are white, hind feet darker. Southern flying squirrels can live for 3 to 5 years and can keep a home range of 1-2 ha. Southern flying squirrels are a highly carnivorous squirrel, feeding on invertebrates, bird eggs, and even birds and nestlings, in addition to seeds, nuts, berries, and fungi. They are strictly nocturnal and are prey for hawks, owls, snakes, and other carnivores (Dolan & Carter 1977) L.L. Master ASM MIL 35

40 Appendix C: Motion Camera Photos 36

41 Armentrout Preserve Red Fox 37

42 Armentrout Preserve White-tailed deer (piebald buck) 38

43 Armentrout Preserve Raccoon 39

44 Armentrout Preserve White-tailed deer (doe with twin fawns) 40

45 Briar Hill Preserve Raccoon 41

46 Briar Hill Preserve White-tailed deer (doe and buck) 42

47 Briar Hill Preserve Raccoons (3) 43

48 Briar Hill Preserve Gray squirrel 44

49 Camp Woods Raccoons (2) 45

50 Camp Woods White-tailed deer (buck in velvet) 46

51 Camp Woods Red fox 47

52 Crossways Preserve White-tailed deer (doe) 48

53 Crossways Preserve - Raccoon 49

54 Crossways Preserve Red fox 50

55 Crossways Preserve Domestic dogs (2) 51

56 Four Mills Nature Preserve White-tailed deer (doe) 52

57 Four Mills Nature Preserve Raccoon 53

58 Timoney Preserve Domestic dog 54

59 Timoney Preserve Coyote 55

60 Timoney Preserve Red fox 56

61 Timoney Preserve White-tailed deer (buck) 57

62 Willow Lake Farm White-tailed deer (doe) 58

63 Willow Lake Farm Red fox 59

64 Willow Lake Farm Coyote (side view) 60

65 Willow Lake Farm Coyote (front view) 61