Dr. Stephen Dinkelacker, Assistant Professor of Biology. Department of Biology, University of Central Arkansas

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1 Title of Project: Effects of fire suppression on two threatened species: forest management implications for Western Diamondback Rattlesnake (Crotalus atrox) and Eastern Collared Lizard (Crotaphytus collaris) conservation Project Summary: The Arkansas Wildlife Action Plan lists habitat conversion and alteration of natural fire regimes due to forestry activities as known or potential problems for both the Western Diamondback Rattlesnake and Eastern Collared Lizard. This project will use mark-recapture and GIS habitat modeling techniques to address the impact of fire suppression on the habitat use of these two threatened species. The results of this study will contribute to the use of prescribed fire as a forest management tool to enhance populations of species of greatest conservation need. Project Leader: Affiliation: Dr. Stephen Dinkelacker, Assistant Professor of Biology Department of Biology, University of Central Arkansas dinkelac@uca.edu Physical Mailing Address: 201 Donaghey Ave, Conway, AR Telephone and Fax: (office) (fax) Project Partners: Dr. David Starkey, Assistant Professor of Biology University of Central Arkansas dstarkey@uca.edu Dr. Jeff Miller, Research Associate University of Central Arkansas millerj@uca.edu B.T. Jones, Nature Interpreter Petit Jean State Park Bt.jones@arkansas.gov Kelly Irwin, Herpetologist Arkansas Game and Fish Commission kirwin@agfc.state.ar.us Total Amount of Project: $87,059 Total Amount of SWG: $28,919 Amount of Matching: $58,140 (University of Central Arkansas) $28,820 Cash Match $29,320 In-Kind Match

2 Explanatory Text Fire is a vital and natural part of many forest ecosystems. It serves to change the mosaic of available habitats by altering canopy and ground cover, litter depth, perch height, light intensity, ground temperatures, and moisture content among others. As a result, many plant species are prohibited from colonizing areas prone to fire, whereas others are free to establish populations in these areas. In the absence of fire, vegetation communities and structures tend to progress through succession stages. In other words, the sparse vegetation that is initially established following a disturbance, such as fire, will be gradually replaced by woody vegetation and ultimately a mature forest. In the past century, anthropogenic fire suppression has resulted in widespread changes in plant communities throughout many areas in the United States. An understanding of how wildlife respond to changes in vegetative structure and the associated abiotic conditions is necessary to understand how populations persist or decline, and disperse within areas managed for biodiversity and low impact human use. Reptiles are particularly vulnerable to the effects of fire suppression because their physiology, behavior, and physical ability to disperse are directly influenced by the temperature and spatial structure of their environment. For example, reptile abundance and diversity are often lower on heavily shaded rock outcrops than on more open sites due to decreased ground temperatures. In addition to thermoregulatory stress, numerous species of snakes and lizards have been threatened by fire suppression because of their inability to disperse between preferred habitat types. In Arkansas, the importance of fire to maintain healthy ecosystem function has only recently been accepted and the restoration of prescribed fire is currently underway in many National Forests, Wildlife Management Areas, and other natural areas. However, fire suppression has been the standard operating procedure of some Arkansas State Parks (i.e., Petit Jean State Park) and is still currently enforced. The Western Diamondback Rattlesnake (Crotalus atrox) is the second largest venomous snake species in the United States, but little information about the life history and ecology of this species is available for Arkansas. The Eastern Collared Lizard (Crotaphytus collaris) is a large stout-bodied lizard that requires open, rocky habitat and is never found in forested terrain. In Arkansas, both species reach their easternmost geographic distributions and inhabit dry, rocky outcrops, glades, and talus slopes in higher elevation mountainous areas (e.g., Petit Jean Mountain, Mt. Magazine, and Pinnacle Mt. State Parks). Although the habitats of these species are similar, their ability to disperse to other suitable habitats differs. For instance, Collared Lizards will not move through dense underbrush and populations tend to occur as discrete groups within patches of available habitat. In comparison, Diamondback Rattlesnakes are able to move easily between patches of suitable habitats. However, these habitats are currently under threat from invasive woody plant species (i.e., maple, ash, elm, gum, cedar) that have established populations in the absence of fire. In the Arkansas State Wildlife Action Plan, habitat conversion and the alteration of natural fire regimes due to forestry activities are listed as known or potential problems impacting the survival of both species. The restoration of glades and implementation of prescribed fire are listed as part of the conservation action plan for Collared Lizards, while more data are currently needed to determine the appropriate conservation actions for Diamondback Rattlesnakes. Interestingly, the Timber Rattlesnake (Crotalus horridus) is considered a generalist species and is found in a variety of habitats including those occupied by Western Diamondbacks and Collared Lizards, as well as in forested habitats. Given its generalist habitat requirements and wide distribution, it is not considered threatened in Arkansas. A comparison of these three species and their different habitat preferences (specialized and generalist) and behaviors (dispersal or inability to disperse) will permit definitive conclusions to be made regarding the impacts of fire on several wildlife species. This project will take place in Petit Jean State Park (Arkansas s first and flagship state park), which is a 3,471 acre area located in the Ouachita Mountains of southwestern Conway County. Petit Jean State Park received over 500,000 visitors in Both species have documented populations within the park. In fact, over the past few years, the number of Diamondback Rattlesnakes found in the human-use areas, such as overlooks and campgrounds, has increased. It is possible that encroachment of woody vegetation

3 into the previously open, rocky areas has forced the Diamondback Rattlesnakes to seek alternative open areas (overlooks or camp grounds) for thermoregulatory and/or food availability purposes. In addition, vegetation encroachment has potentially reduced the available habitat for Collared Lizards. As a result, populations are likely to be small and isolated at Petit Jean State Park. Interestingly, the majority of Collared Lizard sightings occur within the Seven Hollows area that was burned by a wildfire in This project will provide baseline data on the effects of current forest management practices in the habitat utilization by both Diamondback Rattlesnakes and Collared Lizards in Petit Jean State Park. These data will contribute to forest management options that can be implemented at other sites where fire suppression has occurred in Arkansas (e.g., Mt. Magazine and Mt. Pinnacle State Parks, Ouachita and Ozark National Forests). The overall objective of our project is to determine if fire suppression in Petit Jean State Park has resulted in a decline in the available habitat for Western Diamondback Rattlesnakes and Collared Lizards. Specifically, we will test the hypothesis that Western Diamondback Rattlesnakes are restricted to areas that are dry, rocky, and warm with little to no canopy cover. We expect to find that snakes move between these patchy habitats, but may also use man-made areas that bring them in close proximity to park visitors. We expect that Timber Rattlesnakes will use all parts of the park, but tend to avoid areas in close proximity to park visitors. We will also test the hypothesis that Collared Lizards are restricted to similar dry and rocky habitats, yet movements between these habitat patches are exceedingly rare. Finally, we will use GIS to model the potential effects of fire on habitat and to address the question of whether prescribed burning provides additional (open) habitat for these threatened species. Methods: Rattlesnakes will be captured by manually searching suitable habitats, opportunistic captures on park roads, incidental captures in public areas, and in drift fence/pitfall traps. Animals will be handled using tongs, hooks, and a venomous snake bagging system. Twelve Western Diamondback Rattlesnakes and 12 Timber Rattlesnakes will be captured and transported back to the University of Central Arkansas. Each animal will be sexed and measured for body size (length overall or SVL and weight). In addition, each animal will have a PIT tag implanted in its tail. The PIT tag is an electronic tag that can easily be read by an electronic scanner and allows for individual identification without using invasive techniques (i.e., mutilation). Radio transmitters (with 3-5 year battery life) will be surgically implanted into the abdominal cavity of each snake. During surgery, each snake will be anesthetized with isofluorane and the surgical site sutured with cat-gut material. Following surgery, each snake will be housed independently in specially designed and secure housing at the University of Central Arkansas until it resumes eating normally, and has shed its skin at least once. All animals will be released at their capture site or at a location of suitable habitat away from human use areas. Each snake will be located weekly to biweekly during the active season (April through October) and biweekly to monthly during the winter months. At each location, we will record the GPS location, % canopy cover, soil moisture, air temperature, soil temperature, litter depth, nearest tree species, and habitat type. In addition, we will record the same variables at 5 points selected at a random direction and distance from the snake s location. The comparison of habitat use vs habitat availability will permit an analysis of habitat selection. In other words, we can ask the question do snakes select certain habitat characteristics in greater proportion than their availability, or do they avoid certain available habitats? For Collared Lizards, suitable areas will be searched and lizards captured manually or though the use of drift fences and/or pitfall traps. Each lizard will be sexed, measured (length and weight), and an electronic PIT tag inserted into its body cavity. At each habitat where collared lizards are found, we will measure the same habitat variables as measured for the snakes. We will also measure the same variables in the surrounding habitats. We will attempt to capture and trap lizards during their active seasons (April through October). Again, we will address questions of habitat selection for this species.

4 Using a combination of measured habitat variables in conjunction with historic and current digital land coverage images and aerial photographs, we will model the distribution and use of available macro- and microhabitats in Petit Jean State Park. We will then test the prediction that Diamondback Rattlesnakes move between preferred habitats (i.e., dry, rocky, sparse vegetation) that predispose them to human contact, while Timber Rattlesnakes are able to use all parts of the park. In addition, we will test the prediction that Collared Lizards rarely move outside of their small habitat patches and occur in small populations. Measurable Products or Outcomes: This project will result in several measurable outcomes including a report that will be submitted to the Arkansas Game and Fish Commission and Department of Parks and Tourism that outlines the benefits and consequences of fire as a management tool for the conservation of Diamondback Rattlesnakes and Collared Lizards. During the study, we will also gain valuable data regarding population density and structure of two threatened species of reptiles in Arkansas. In addition, we will generate scientific manuscripts describing the comparative habitat selections and movements of two rattlesnake species in Arkansas, as well as the potential use of fire as a tool to facilitate conservation of Collared Lizards and Diamondback Rattlesnakes. Finally, our program will be highly visible to the general public who visit the park, especially on nature hikes and tours, and will help to raise the profile of the Wildlife Action Plan. Existing Resources: The main advantage of this project is that both species, which are listed as species of greatest conservation need, are found in Petit Jean State Park. In addition, because these species are found in other state parks in Arkansas, this project will serve as a demonstration project that can be replicated at other parks within the state. Furthermore, the application of prescribed burning to the management of both vegetation and animal communities will integrate Wildlife Action Plan priorities with other natural resource efforts at the state level. Additionally, experts from multiple organizations are involved and are strategically placed near Petit Jean State Park. Dr. Dinkelacker and Dr. Starkey are within a 45 minute drive from the study site and will coordinate and conduct the telemetry and animal capture work. Dr. Jeff Miller is also at UCA and is highly experienced with GIS modeling procedures and will coordinate the development of the habitat and fire models. BT Jones is an employee of Petit Jean Park and will participate in a majority of the incidental rattlesnake captures as well as surveys for collared Lizards. Kelly Irwin is a herpetologist for the Arkansas Game and Fish Commission and will provide technical expertise in trapping methodology and assist in the field. Handling of Longterm Maintenance: This project is designed to produce results within the 2-year time period described in the RFP. However, the transmitters used in this study will last for 3-5 years. As such, we will continue to monitor the animals past the formal study period. This will strengthen our results and increase the duration of project visibility to the public. BT Jones and other staff members of Petit Jean Park will be trained and supplied with snake handling equipment so that they will be able to continue to plot incidental rattlesnake and collared lizard captures and locations. In the event that fire does occur on the park (naturally or prescribed), we will have the baseline data to experimentally test and validate our model s effectiveness. Total Project Budget: State Wildlife Grant UCA Cash Match UCA In-Kind Salary/ Benefits: $0 $28,820 $28,820 Operating Expenses: $7,100 $0 $500 Capital Expenses: $19,190 $0 $0 Indirect Costs: $2,629 $0 $0 $28,919 $28,820 $29,320

5 Qualifications of Individuals Dr. Stephen Dinkelacker received a Masters degree in Applied Ecology and Conservation Biology from Frostburg State University and a Doctorate in Zoology from Miami University. In the past, he has received Arkansas SWG money to study the biology and habitat selection of Western Chicken Turtles in Arkansas. Currently, he is an Assistant Professor at UCA and runs the Laboratory for Herpetological Research and Conservation (LHRC). His lab currently supports 4 graduate students that work on projects studying Western Chicken Turtles, Alligator Snapping Turtles, American Alligators, and Pitvipers (including Rattlesnakes, Cottonmouths, and Copperheads). One of the primary focus areas of the laboratory is to examine anthropogenic impacts on reptile populations. Towards this end, Dr. Dinkelacker has studied the effects of roadways on Blanding s turtle populations and nesting ecology, commercial harvest and recovery of Alligator Snapping Turtles, and the effects of harvest on population dynamics of American Alligators. As such, the impacts of anthropogenic fire suppression on rattlesnake and lizard habitat use is a topic that the lab is equipped to investigate. Dr. David Starkey received a Masters degree in Biology from the University of Illinois and a Doctorate in Genetics from Texas A&M University. Dr. Starkey is currently employed as an Assistant Professor in the Department of Biology at UCA. Dr. Starkey s research at UCA currently focuses on the population genetics of Western Chicken Turtles and Grotto Sculpin. Additionally, Dr. Starkey is working on several other turtle related projects, including a survey of the diversity in the stinkpot turtle, the population genetics of the painted turtle, and the systematics of the snapping turtle. Dr. Jeff Miller received a Masters degree in Environmental Studies from the University of Montana at Missoula and a Doctorate in Zoology from the University of New England (Armidale, NSW, Australia). Dr. Miller is currently employed as a Research Associate and Visiting Assistant Professor at the University of Central Arkansas. Previously, he worked for Queensland Parks and Wildlife Service where he designed and conducted conservation-management programs primarily on the Saltwater Crocodile (Crocodylus porosus) and Sea Turtles. His other research interests focus on spatial modeling of animal abundance and habitats, reproductive physiology of reptiles, and tardigrade ecology. Dr. Miller contributes geographic analysis to several projects underway in the LHRC and provides GIS advice and training to post graduate students. BT Jones received a Master s degree in Education from the University of Arkansas at Little Rock. Currently, he is a Nature Interpreter at Petit Jean State Park in Arkansas. Mr. Jones s duties include providing natural and historic programming for the public at Petit Jean State Park as well as resource management. He is an advocate for the understanding and protection of wilderness and intact ecosystems. Kelly Irwin received a Master s Degree in Wildlife and Fisheries Sciences from Texas A&M University and has been employed as the herpetologist for the Arkansas Game and Fish Commission since Mr. Irwin s duties include conducting, coordinating, and managing scientific research and management projects on reptile and amphibian species native to Arkansas. Recent major projects have focused on the conservation and management of Ozark Hellbenders, American Alligators, and aquatic freshwater turtles.