SWCHR Volume 3, Issue 2 BULLETINSummer 2013

ISSN 2330-6025

Conservation - Preservation - Education - Public Information Research - Field Studies - Captive Propagation The SWCHR BULLETIN is published quarterly by the SOUTHWESTERN CENTER FOR HERPETOLOGICAL RESEARCH PO Box 624, Seguin TX 78156 www.southwesternherp.com email: [email protected] ISSN 2330-6025

OFFICERS 2013-2014 COMMITTEE CHAIRS

PRESIDENT COMMITTEE ON COMMON AND SCIENTIFIC Toby Brock NAMES Gerry Salmon VICE PRESIDENT Gerry Salmon RANGE MAP COMMITTEE (vacant) INTERIM SECRETARY Gerald Keown AWARDS AND GRANTS COMMITTEE Gerald Keown EXECUTIVE DIRECTOR Gerald Keown COMMUNICATIONS COMMITEE Gerald Keown BOARD MEMBERS AT LARGE John Lassiter ACTIVITIES AND EVENTS COMMITTEE Orion McElroy Toby Brock D. Craig McIntyre NOMINATIONS COMMITTEE BULLETIN EDITOR Gerald Keown Chris McMartin EDUCATION COMMITTEE ABOUT SWCHR (vacant) Originally founded by Gerald Keown in 2007, SWCHR is a 501(c) (3) non-profit association, governed by a board of directors and MEMBERSHIP COMMITTEE dedicated to promoting education of the Association’s members Toby Brock and the general public relating to the natural history, biology, tax- onomy, conservation and preservation needs, field studies, and CONSERVATION COMMITTEE captive propagation of the herpetofauna indigenous to the Ameri- can Southwest. Robert Twombley

THE SWCHR LOGO JOINING SWCHR

There are several versions of the SWCHR logo, all featuring the For information on becoming a member please visit the member- Gray-Banded Kingsnake (Lampropeltis alterna), a widely-recognized ship page of the SWCHR web site at reptile native to the Trans-Pecos region of Texas as well as adjacent http://www.southwesternherp.com/join.html. Mexico and New Mexico.

ON THE COVER: Northern Black-tailed Rattlesnake, Crotalus molossus molossus, Pima County, AZ (Orry Martin). This photograph was voted the winner of the ©2013 Southwestern Center for Herpetological Research. The SWCHR Bul- 2012 SWCHR Award for Excellence in Herpetological Photography. letin may not be reproduced in whole or in part on any web site or in any other publication without the prior explicit written consent of the Southwestern Center BACKGROUND IMAGE: Elephant Tusk, Big Bend National Park, TX (Chris for Herpetological Research and of the respective author(s) and photographer(s). McMartin) SWCHR Bulletin 15 Summer 2013 TABLE OF CONTENTS

A Message from the President, Toby Brock 16

Herpetofaunal Biodiversity Survey along the Wasatch Mountains, Utah: 17 A Focus on Morgan and Weber Counties, Kyle Shaney and Jonathon C. Marshall

Predation on a (Tibicen sp.) by a Trans-Pecos Copperhead, 23 pictigaster (Serpentes: Viperidae), Arik Beal

An Analysis of the “Snake Measurer” Software Tool, Chris McMartin 24

Mating Pair of Texas Horned Lizards (Phrynosoma cornutum) on a New Mexico 27 Roadway (Lacertilia: Phrynosomatidae), Chris McMartin and Ron Govreau

A CALL FOR PAPERS

Are you a field herpetologist or a herpetoculturist working with species native to the American Southwest? Do you have a paper or an article you have written for which you would like to find a permanent repository? Want to be assured you will always be able to share it with the world? Submit it to the SWCHR Bulletin for possible publication. Submitted manuscripts from SWCHR members, as well as non-members, will be considered.

To be accepted for publication, submissions must deal with herpetological species native to the American Southwest. Such topics as field notes, county checklists, range extensions, , reproduction and breeding, diseases, snake bite and venom research, captive breeding and maintenance, conservation issues, legal issues, etc. are all acceptable. For assistance with formatting manuscripts, search ‘scientific journal article format’ on the internet and tailor the resultant guidance to suit.

Previously published articles or papers are acceptable, provided you still hold the copyright to the work and have the right to re-publish it. If we accept your paper or article for publication, you will still continue to be the copyright holder. If your submission has been previously published, please provide the name of the publication in which it appeared along with the date of publication. All submissions should be manually proofed in addition to being spell checked and should be submitted by email as either Microsoft Word or text documents.

Send submissions to [email protected]. SWCHR Bulletin 16 Summer 2013 A Message from the President

The big news for the summer here at SWCHR is the great success of the second annual Snake Days event, which was again held in Sanderson, Texas. The event featured several excellent speakers, and among them our very own SWCHR Bulletin editor, Chris McMartin. This year’s Snake Days was a great thing for SWCHR in that we got a lot of public exposure during the event. We held our first official Rendezvous – Texas on the opening day of Snake Days, and signed up several new members that day, with a total of nine new members during the weekend. The Rendezvous was a meet and greet for all interested herpers, with free barbecue and drinks. It went very well, with most folks enjoying the fajitas, beans and sodas. During Snake Days, around $5,000 was again raised and donated to the Texas Parks and Wildlife Department for herp-related projects. TPWD had three speakers this year, including state herpetologist Dr. Andy Gluesenkamp who updated everyone on the projects benefiting from last year’s fundraiser. Aside from the business, presentations, and camaraderie, lots of nighttime field herping happened during the weekend, with several very nice herps found.

In this issue of the Bulletin Kyle Shaney details a very thorough survey of the herpetofauna of Morgan and Weber Counties along the Wasatch Mountains in Utah. Arik Beal tells us of finding a Trans-Pecos Copperhead feeding on a cicada. Chris McMartin reports his findings on the accuracy of the “Snake Measurer” program in a detailed article. Chris also documents an observation by Ron Govreau of a pair of Texas Horned Lizards mating on a highway.

In addition to the aforementioned Rendezvous – Texas, SWCHR also had a few other memorable happenings during the Snake Days weekend. We had our first meeting of the Board of Directors where all current Board Members attended in person, and accomplished quite a lot of business, including some needed amendments to our Articles of Association. The Board also awarded Chris McMartin an Honorary Life Membership in appreciation of all that he does for the association – one of which is finding time to edit the Bulletin even while he was deployed overseas by the United States Air Force! We also bestowed an award of appreciation on Scott DeGraff, the proprietor of the Desert Air Motel in Sanderson, Texas, which was SWCHR headquarters during the event and the location of the Rendezvous – Texas. SWCHR also sponsored the Snake Days photo contest, with Chris McMartin winning third place, and Travis Dimler winning both second place and the Best in Show awards – all excellent photos of beautiful ! The 2013 Snake Days event was truly a historical event for SWCHR.

Photo by Pearl Brock SWCHR Bulletin 17 Summer 2013

Herpetofaunal Biodiversity Survey Along documentation throughout the region, we found a number of museum specimens collected by various institutions. The number the Wasatch Mountains, Utah: A Focus on of individuals found in these collections is also relatively small and Morgan and Weber Counties presents no historical information on the status of herpetofaunal distributions and densities in the region. This small amount of by Kyle Shaney data is insufficient in determining the current status of species or Department of Biology, University of Texas—Arlington, 701 South Nedderman Drive, Arlington TX 76019 populations in the area. and Jonathon C. Marshall Department of Zoology, Weber State University, The Wasatch lies along the urban-wildland interface, allowing 2505 University Circle, Ogden, Utah, 84408 human influence to have potentially negative effects on population densities, ranges, and species richness. We speculate that urban Abstract development, agriculture, outdoor recreation, and competition from introduced species are four major factors that may contribute In a recent biodiversity survey conducted over the course of two to pressure on wildlife here. Our study area contains numerous summer field seasons (June-October) we documented twelve reptile roads, agricultural fields, home developments, and hiking trails. and amphibian species in a section of the central Wasatch Mountain Species that are limited to small areas and exposed to habitat Range in northern Utah. Of these twelve species, five snake, three fragmentation have only a small area to move as pressures increase frog, two lizard, one turtle, and one salamander species were found. (Forman et. al. 1998). There is very little historical knowledge of The area is roughly 100 square miles and consists of four main how these pressures are affecting the herpetofaunal species in this habitat types: dry oak forest, moist mixed conifer forest, high alpine region. Consistent survey work would aid in better understanding tundra, and agricultural lands. The lack of historical data along the these effects. Wasatch Front indicates the need for additional survey work. The native species along the Wasatch Front are exposed to numerous pressures including urban development, agriculture, outdoor recreation, and competition with introduced species. Our study serves as a starting point for accumulating more data regarding the current status of the various herpetofaunal species throughout the region.

Introduction

Accurate survey data is important in assessing the status of various species of wildlife and allows wildlife officials to apply proper management where necessary. With the exception of a few specific research papers and projects, the status of most reptile and amphibian species along the Wasatch Mountain Range of Utah (Wasatch) is relatively unknown (Fitch and Maslin, 1961; Jones, 1999; Jones and Mellon, 2008; Mulcahy et al 2002). Without determining the status of these species over time, it is difficult to monitor changes in response to new or increasing pressures. In our study we conducted a herpetofaunal survey along a portion of the Wasatch and compared our data with historical data we were able to locate. This project serves as a starting point for gathering information on the status of multiple herpetofaunal species throughout the region and highlights the need for more consistent survey work.

The UDWR supplied us with their documented herpetofaunal survey information for Davis, Morgan, and Weber counties. Unfortunately the UDWR has documentation of a relatively low number of Fig. 1. Study area outlined in blue. Upper image is for geographical reference. Imagery from Google Maps (http://maps.google.com); study area outlined by the author. individuals over the past 100 years within these three counties. Within Weber and Morgan counties (The site of our study area) the UDWR has documented less than 100 herpetofaunal specimens in Methods the last 87 years (earliest reliable UDWR documentation, 1926) and only five specimens have been documented within our chosen 100 The study area lies immediately adjacent to Ogden, Utah and covers square mile study area. In searching online resources (e.g., https:// approximately 100 square miles (Figure 1, above). We chose this www.herpnet.com and specific institution databases) for historical area arbitrarily, because it is an area of manageable size representing a larger region of similar habitat types. The area is predominantly SWCHR Bulletin 18 Summer 2013

made up of four distinct vegetation zones: dry oak forest (arid areas navigate), ranging from approximately 1.5 to 4 miles each time. made up of mostly oak trees, sagebrush, and various grasses), moist Surveys were completed four times per week during daylight and mixed conifer forest (a relatively moist habitat with a mix of firs, once per week after sunset. The night surveys were done on the aspens, and various shrubs and grasses), high alpine tundra (high same day as one of the daytime surveys. Survey times varied from elevation areas, made up of low growing shrubs and grasses), and 9:00 a.m. to 9:00 p.m. during the day and from 10:00 p.m. to 2:00 agricultural areas (any areas that have been cultivated for farming a.m. at night. Each week we chose the same time frames during or ranching and now vary from natural habitat) (Figure 2 below). the day to survey each of the four habitat types (we then chose a The majority of the west- and south-facing slopes consist of dry different time frame the next week and repeated that cycle): either oak forest, agricultural lands, and high alpine tundra. The majority 9:00 a.m. to 1:00 p.m., 1:00 p.m. to 5:00 p.m., or 5:00 p.m. to 9:00 of the north- and east- facing slopes consist of moist mixed conifer p.m. Night surveys were always from 10:00 p.m. to 2:00 a.m. We forest, agricultural lands, and high alpine tundra. This variation surveyed a different habitat type each time we did night surveys. in vegetation zones within a relatively small area is due to highly The decision to only do one night survey per week was arbitrary, variable topography. Within our study area, elevations range from based on the fact that we expected to see fewer individuals at night roughly 4,200 to 11,000 feet. This varied habitat and vegetation than during the day (there are few nocturnal species in the area and provides multiple niches for herpetofaunal species. based on personal experience we expected to see fewer individuals). Surveys were conducted by utilizing various trails, roads, riverbeds, We surveyed four habitat types over the course of a four month and anywhere clear enough to walk freely. When bodies of water period between June and October of 2011, and again between June were located (streams, rivers, ponds, and lakes), we spent between and October of 2012. We chose these time frames because they 30 minutes and one hour searching for aquatic species. All locations anecdotally represent the peak of herpetofaunal activity within the were basically opportune; however, we were able to spend less time region (based on our personal experience most, but not all, species surveying agricultural areas (due to lack of access, or the small size are highly active during this time frame). We conducted surveys of areas to which we were permitted access) and higher elevation four times per week (three to five hours, depending upon size of areas (due to rough terrain) than dry oak forest and mixed moist the area and amount of time we were allowed to spend there if on conifer forest. private land) over the course of the study period. We surveyed each habitat type once a week. A single individual was involved Over the course of both field seasons we estimate that we spent a in surveys on a constant basis, while occasionally two to three total of 575 hours surveying all four habitats: 175 hours in the dry others would assist. While surveying we covered varying distances oak forest, 175 hours in the moist mixed conifer forest, 125 hours depending upon the habitat type (rough terrain took longer to on the agricultural lands, and 100 hours in the high alpine tundra.

Fig. 2. The four distinct vegetation zones we defined within our study area. Clockwise from the upper left, they are Dry Oak Forest, Agricultural Lands, High Alpine Tundra, and Moist Mixed Conifer Forest. Photographs by the author. SWCHR Bulletin 19 Summer 2013

Approximately 20 hours of each total was spent surveying each data to the number of individuals we found in our small study and habitat at night. Flipping rocks and logs and digging through leaf then compared that data to the number of individuals where the litter were used to find individuals that were not visible, similar to date of documentation is unknown. The graph highlights the lack other herpetofaunal biodiversity surveys (Leache et al. 2006). After of recorded data prior to our study. dark we used headlamps and listened for anuran calls. We collected all specimens by hand for identification, with the exception of one venomous species which was not captured (it was identified Family Scientific Name Common Name from a distance of approximately 5 feet). After being identified, Colubridae Charina bottae Rubber Boa (E)(Un) all captured specimens were released. Information including Yellow-bellied Racer (E) GPS coordinates, elevation, slope aspect, temperature, and time Coluber constrictor of day were also recorded for each sighting and/or capture. All Diadophis punctatus Ring-necked Snake (Q) data is recorded and available through the Weber State University Hypsiglena torquata Night Snake (Q) Department of Zoology herpetology collections. Masticophis taeniatus Striped Whipsnake (E) (Un) According to UDWR distribution maps, “Peterson’s Field Guide Pituophis catenifer Gopher Snake (E) to Western Reptiles and Amphibians: Third Edition” (PFGWRA) Thamnophis elegans Terrestrial Garter Snake and museum records, we have estimated there are 22 reptile and (E) amphibian species known to be found within our study area and Thamnophis sirtalis Common Garter Snake roughly five species that might be found (questionable based on (E) their known distribution; see Table 1, right). This includes the Viperidae Crotalus oreganus Western Rattlesnake (E) introduced species known to be found within the area. Teiidae Aspidoscelis tigris Western Whiptail (E) We took photographs of the study area using a 3.0 megapixel Sony Phrynosomatidae Crotaphytus bicinctores Great Basin Collared digital camera. We also took photographs of every individual Lizard (Q) captured for confirmation of identification, and took a photo of Phrynosoma hernandesi Short-horned Lizard (E) the venomous snake from a safe distance. However, not all photos (Un) may be considered to be “identification quality” (e.g. due to lighting Sceloporus graciosus Sagebrush Lizard (E) issues). Geographic coordinates, elevation, and time were taken Scincidae Eumeces skiltonianus Western Skink (Q) using a Lowrance GPS unit. Coordinates were recorded as latitude Emydidae Chrysemys picta Painted Turtle (Int) (E) and longitude, referenced using the WGS84 datum and converted Bufonidae Anaxyrus boreas Boreal Toad (E)(Un) into decimal degrees. We used this data to better understand Anaxyrus cognatus Western Toad (E)(Un) patterns in species distributions throughout the area. Due to UDWR regulations, we did not include any exact GPS coordinates. Anaxyrus woodhousii Woodhouse’s Toad (E) (Un) Slope aspect was determined with a Coleman compass. We used Google Maps (https://maps.google.com) to show our study area in Scaphiopodidae Spea intermontana Great Basin Spadefoot Toad (E)(Un) detail (Figure 1). Hylidae Pseudacris regilla Pacific Tree Frog (E)(Un) We used PFGWRA, UDWR data, and museum collections Pseudacris triseriata Western Chorus Frog (E) (Brigham Young University and Carnegie Museums) to identify Ranidae Lithobates catesbeianus Bullfrog (Int)(E) species expected to be found within our study area. We used the Lithobates clamitans Green Frog (Int)(E) same PFGWRA to assist in identifying all species we documented. Lithobates luteiventris Columbia Spotted Frog Of all species potentially found within the study area, we consider (E)(Un) five similar enough to be difficult to readily distinguish from Lithobates pipiens Leopard Frog (E)(Un) one another: the terrestrial garter snake (Thamnophis elegans) and Ambystomatidae Ambystoma tigrinum Tiger Salamander (E) common garter snake (Thamnophis sirtalis), and Woodhouse’s Toad (Anaxyrus woodhousii), Great Plains Toad (Anaxyrus cognatus), and Table 1. Species potentially found within our study area, based on field guide Western Toad (Anaxyrus boreas). distribution maps, museum records, and database searches. Species are listed as being extant (E) for species that have been documented within the two counties we We compared our data to all data provided by the UDWR from surveyed at any point in time (22 total). Species listed as (Q) are species in question, because they have never been documented in the area, but their range may reach our the past 87 years. Due to state regulations, the data provided area of study (4 total). Species are listed as (Un) if they are a species that has been by the UDWR had to be masked within one square mile of the documented in the past, but were not found in our study (10 total). actual documented location. We also compared our data with all data available online, to include all online databases associated with herpnet.com, as well as any independent institutions found throughout Utah. We used a bar graph to compare the amount of Results data found by all other sources since 1870 (Figure 3). It shows all We documented a total of twelve species throughout the course data we could find from other sources and groups the data by decade of our survey: five snake, three frog, two lizard, one turtle, and (total of all individuals, representing all species). We compared this one salamander species. Species numbers that we documented SWCHR Bulletin 20 Summer 2013

in this project are depicted in Table 2 below. The individuals we articles discussed herpetofauna in other parts of that state of Utah, documented were found between 4,449 and 6,565 feet in elevation. with no overlap with our study area. While conducting a search for The majority of species (five) were found within dry oak forest available herpetofaunal documentation within the region between and the rest were found on agricultural land (four) or moist mixed 1878 and 2013, we located only 109 individual museum records conifer forest (three). No individuals were found in the high alpine online (including all herpetofaunal species) from Weber County and tundra habitat. seven individual records from Morgan County (herpnet.com). We only found one institution not listed on herpnet.com, the Carnegie Family Scientific Name Common Name Museum, that had herpetofaunal data from our study region. Many of the available records lacked sufficient data, including the date Colubridae Coluber constrictor Yellow-bellied Racer (DOF) they were found. Based on these museum collections, we have provided a breakdown of the historical documentation available Pituophis catenifer Gopher Snake (DOF) online for Weber and Morgan counties (Figure 3, next page). Thamnophis elegans Terrestrial Garter Snake (MM) Thamnophis sirtalis Common Garter Snake Discussion (AL) Updated herpetofaunal survey data is important in terms of Viperidae Crotalus oreganus Western Rattlesnake (DOF) conservation biology and understanding how increasing pressures affect population densities. The Wasatch Front is underrepresented Teiidae Aspidoscelis tigris Western Whiptail (DOF) in this regard. The Rocky Mountains (of which the Wasatch is a part) are of major biogeographic importance (Zamudio et al. 1997). As Phrynosomatidae Sceloporus graciosus Sagebrush Lizard part this region, our study area serves as a starting point to establish (DOF) the status of herpetofaunal species along underrepresented portions Emydidae Chrysemys picta Painted Turtle of the Wasatch and the rest of the Rocky Mountains. Although all (Introduced) (AL) the species we have found have been found in previous records Hylidae Pseudacris triseriata Western Chorus Frog at some point, there has not been consistent documentation over (MM) the years (Figure 3), and this is required to establish the status of Ranidae Lithobates catesbeianus Bullfrog many species. Aside from Western Toad studies that are complete (Introduced) (AL) (Goebel et al. 2009) or are in progress through the United States Lithobates clamitans Green Frog Forest Service (Keinath and McGee, 2005; Jones, 2008), there have (Introduced) (AL) been very little data recorded on reptile and amphibian population Ambystomatidae Ambystoma tigrinum Tiger Salamander densities along the Wasatch. Further population analyses should be (MM) considered in order to establish what effects increasing pressures Table 2. Species identified in our survey period. All introduced species are identified may have on reptile and amphibian species along the Wasatch. as (Introduced). The habitat types that each species was found in are listed next to Low herpetofaunal densities could be an indicator of larger the species as well (Moist mixed conifer forest= MM, High alpine tundra= HAT, Dry oak forest= DOF, and Agricultural lands= AL). environmental issues (Stuart et. al. 2004).

The status of these species can only be obtained by continuing to Although studies were conducted at various times of day and night, survey the area. Populations found in isolated areas are also subject the majority of individuals were found in late afternoon. Ten of to additional pressures, including temperature changes (Sinervo twelve species identified were found between 5:00 p.m. and 7:00 et al. 2010). Out of the twelve species we documented, three of p.m. Only two species were found in morning hours and were those were introduced species—Painted Turtles, Green Frogs and found between 10:00 a.m. and 12:00 p.m. Temperatures in which Bull Frogs. Further research within the region could help establish individuals were found ranged from 80 to 92 degrees Fahrenheit. whether these nonnative species are having an effect on native species. Species were only found on west-facing, southwest-facing, and northeast-facing slopes, although all slope aspects were surveyed There are also a number of sensitive species (as defined by UDWR) without bias. The GPS coordinates, elevation data, slope aspect, within our study area. There is one species of frog (Columbia temperature, and time of day when all individuals were found Spotted Frog, Lithobates luteiventris) listed as a “Conservation were also documented and that data was deposited at Weber State Agreement Species” and two species of toad (Western Toad University. All individuals were found during daylight hours, and Great Basin Toad) listed as “Wildlife Species of Concern.” although night surveys were conducted weekly. The decline of the Western Toad specifically has been noted in numerous areas throughout the western United States (Bull, Carey, In addition to our field observations, we did a thorough search 2008). We did not locate any of these three species during our for historical documentation of reptile and amphibian species survey of the study area. There are no reptiles on the UDWR throughout our study area. We identified research papers that discuss sensitive species list within our study area, but there is very little herpetofauna in various parts of Utah (Jones, 1999; Bosworth III, population data on Utah’s species along the Wasatch. With such 2003; Keinath and McGee, 2005). The majority of these research little documentation it is possible that other species may fall into the SWCHR Bulletin 21 Summer 2013

Fig. 3. The number (ranging from 0-50 individuals) of historical herpetofaunal records available online for Morgan and Weber Counties Utah (From Utah institutions only). Records are grouped by the decade in which the record occurred, to visualize the relatively low number of records over time. Weber State University records are represented as (WSU) and show how our two seasons of field surveys are responsible for more documentation information than any other decade. Information shown in black represents all records where the date was unknown. Chart by the author. SWCHR Bulletin 22 Summer 2013

category of sensitive species. Forman, R. T., and L. E. Alexander. “Roads and Their Major Ecological Effects.” Annual Review of Ecology and Systematics 29:207– It is important to note we only found twelve species during our 231, 1998. survey, compared to the 22 herpetofaunal species identified from Morgan and Weber counties historically. The difference in Goebel, Anna M., T. A. R., Paul Stephen Corn, and Richard G. species richness encountered may be partially attributed to survey Olmstead. “Mitochondrial DNA evolution in the Anaxyrus boreas techniques; however, many species we did not find have only been species group.” Molecular Phylogenetics and Evolution 50: 209-225, found sporadically in the past. The species we found are likely the 2009. most common species in the area. Jones, A. The Status of Utah’s State-Listed Sensitive Herpetofuana, and For a more accurate idea of herpetofaunal population densities, a Implications of New Wilderness Designation Within Their Range. The more comprehensive study should be conducted. A larger study Southern Utah Wilderness Alliance, 1999. area and longer sample period should be considered. Our studies were conducted from June through October. However, some Jones, J.L. and C. Mellon. “Boreal Toad (Anaxyrus (=Bufo) boreas herpetofaunal species in this area may be more active during spring boreas) Statewide monitoring Summary.” Utah Division of Wildlife and early summer. The lack of documentation for some species in Resources 9(30), 2008 our study may be due to the time of year studies were conducted, rather than low population densities. Keinath, D. and M. McGee. Boreal Toad (Bufo boreas boreas): A Technical Conservation Assessment. USDA Forest Service Assessment, Attempts to survey all vegetation zones more thoroughly may be 2005. difficult, but are important for acquiring accurate data. Due to lack of access and rough terrain, our surveys on agricultural lands and Leache’, A. D., M. Rodel, C. W. Linkem, R. E. Diaz, A. Hillers, high elevation areas were not as thorough as the dry oak forest and M. K. Fujita. “Biodiversity in a Forest Island: Reptiles and and moist mixed conifer forest. This lack of survey time spent in Amphibians of the West African Togo Hills.” Reptile and Amphibian agricultural lands and high elevation areas could also explain the Conservation 4:22-45, 2006. low herpetofaunal numbers documented in our study. The Western Toad and Columbia Spotted Frog are two species we did not find in Mulcahy, Daniel G., M. R. C., joseph R. Mendelson III, Becky L. our study that are likely to be found on agricultural land. Williams, Paul C. Ustachi. “Status and Distribution of Two Species of Bufo in the Northeastern Bonneville Basin of Idaho and Utah.” The status of herpetofaunal species in this region, as well as the Herpetological Review 33, 2002. effect of introduced species on native species, is largely unknown. This study may serve as a starting point for future research. Sinervo, B., F. Méndez-de-la-Cruz, D. Miles, B. Heulin, E. Bastiaans, M. Villagrán-Santa Cruz, R. Lara-Resendiz, N. Martínez-Méndez, M. L. Calderón-Espinosa, R. N. Meza- Lázaro, et al. “Erosion of Acknowledgments Lizard Diversity by Climate Change and Altered Thermal Niches.” Science 328:894-899, 2010. We would like to thank the following Weber State University undergraduate students for help with locating and identifying Stebbins, R. C. Peterson’s Field Guide: Western Reptiles and Amphibians, specimens in the field: Danielle Aranda, Andrew Corbin, Tammy 3rd ed. Houghton Mifflin Company, New York, 2003. Edwards, Jeremy Green, Seth Green, Patrick Kearns, Randi Rollins, and Cory Viegel. Stuart, S. N., J. S. Chanson, N. A. Cox, B. E. Young, A. L. Rodrigues, D. L. Fischman, R. W. Waller. “Status and Trends of Amphibian Declines and Extinctions Worldwide.” Science 306:1783-1786, 2004. Literature Cited US Fish and Wildlife Service. Status Review for the Columbia Spotted Bosworth III, W. R. “Vertebrate Information Compiled by the Frog (Rana luteiventris) on the Wasatch Front, Utah, 2002. Utah Natural Heritage Program: A Progress Report.” State of Utah Department of Natural Resources, Division of Wildland Zamudio, R. K., B. Jones, and R. H. Ward. “Molecular Systematics Resources-Utah Natural Heritage Program, 2003. of Short-horned Lizards: Biogeography and Taxonomy of a Widespread Species Complex.” Systematic Biology 46:284-305, 1997. Bull, E., and C. Carey. “Breeding Frequency of Western Toads (Bufo boreas) in Northeastern Oregon.” Herpetological Conservation and Biology 3:282-288, 2008.

Fitch, Henry S. and T. P. Maslin. “Ocurrence of the Garter Snake, Thamnophis sirtalis, in the Great Plains and Rocky Mountains.” University of Kansas Publications 13(5): 289-308, 1961. SWCHR Bulletin 23 Summer 2013 Predation on a Cicada (Tibicen sp.) by a Trans- hesitation. It looks less and less likely that any stool sample will be representative of what the snake consumed in the wild. However, it Pecos Copperhead, Agkistrodon contortrix is readily apparent the Trans-Pecos copperheads of Sanderson, Texas pictigaster (Serpentes: Viperidae) are dining on .

by Arik Beal

[Editor’s note: Cicadas are well documented as a favored prey item for copperhead subspecies in the southern and eastern United States. Most accounts describing copperhead prey items are generalized to the species level. This is the first report I have seen specifically of a Trans-Pecos copperhead consuming a cicada.]

My companions and I were beating the bushes at the base of the mesa south of the train tracks in Sanderson, Texas on 8 June 2013. The group consisted of me, Gwen Gaal, and her two young children. At approximately 9:45 p.m. I was walking between prickly pear patches and walked around one adjacent to a gravel road when I noticed the color contrast between the snake and substrate. I focused my headlamp on it and immediately saw it was a Trans-Pecos copperhead, Agkistrodon contortrix pictigaster. When my eyes located the head I noticed it was in the process of consuming one of the adult cicadas I had been seeing throughout our search [Editor’s note: presumably Tibicen texanus or a closely-related species, as their calling is heard in the area during the day]. The adult cicada was halfway down the snake’s mouth head first. The snake was writhing around and I could see it was trying to expel the cicada in an attempt to flee.

Unfortunately with the chaos of kids around, and headlamps going everywhere, it was not possible to observe and photograph the snake This adult male Trans-Pecos copperhead, Agkistrodon contortrix pictigaster, was found with the cicada. It managed to get the cicada out of its mouth and devouring a cicada south of Sanderson, Texas. Photo by the author. start crawling off rapidly which is when I pinned it with the handle of my snake hook and got control of the head. I then walked back to our vehicle to find a safe container in which to place the snake. After doing so, I returned to the location to search for more snakes, and when we got to the exact spot, we could hear a cicada calling in a constant and unusual manner. I did a cursory search for the cicada as I was curious as to what, if any, effects the copperhead’s venom had on invertebrates but I did not locate it. The cicada’s “snapping” was definitely within a 4-foot radius of where the snake was caught but whether or not it was the same one is speculative. There were no other cicadas calling in the area and it is my opinion it was the same one since, it was such an unusually constant snapping sound; but again, I cannot be certain since I never found it.

The encounter occurred in an open area about one foot from a prickly pear stand, on a substrate of very small gravel (about the size of aquarium gravel). The snake seemed to have a significant bulge when it was found that wasn’t as noticeable on 16 June. With the number of cicadas in the area I would not be surprised if this snake was gorging itself on them.

The snake, measured at just under 26 inches long and determined to A cicada (Tibicen sp., presumably T. texanus or another closely-related species) found near Pandale, Val Verde County, Texas. The species identification is based on the be male via cloacal probing, has been retained for further study. As sound of the male’s call. There are numerous species of cicada found in west Texas of 22 June, the snake still had not defecated. I was keeping it in a and the T. texanus complex consists of several species difficult to distinguish in the barren tub in an unused rack and it ingested one small pinky mouse, field. Photo by Chris McMartin. and envenomated but did not consume another. I left a fuzzy mouse in the cage with it overnight 21 June and it went untouched. The morning of 22 June I caught a Mediterranean gecko (Hemidactylus turcicus) and placed it in the tank, and it was devoured without SWCHR Bulletin 24 Summer 2013 An Analysis of the “Snake Measurer” Software are detailed equations to determine these errors mathematically, but I was more comfortable performing some “hands-on” work to find Tool out for myself. by Chris McMartin I must caveat my results with a disclaimer that they are only valid Anyone who has ever attempted to get an accurate measurement of for my particular camera model, and your results may vary but could a living, squirming reptile or amphibian has undoubtedly met with easily be determined with your own favorite photography equipment. some degree of frustration; animals tend not to rest patiently next My camera is a Canon SX-20IS, with a CCD sensor size of 1/2.3” to a ruler. One remedy is to take a photograph of the with (6.17mm x 4.55mm) and equivalent focal lengths from 28mm to an object of known size, then using that object to get an estimate 560mm. of the animal’s size. With the nearly-simultaneous advent of both digital photography and people interested in solving the animal- measuring problem, it seems inevitable that someone would develop an application whereby the naturalist can measure an animal using a virtual “string,” and compare its length to the length of another object in the image. With the Serpentine Widgets “Snake Measurer” tool, we have that capability.

Corn snake enthusiast Charles Pritzel launched his web site, http://serpwidgets.com, in 2000, with his “Snake Measurer” application made available as a downloadable program the following year—this is the version I have used successfully for the past nine years. Recently Mr. Pritzel updated the code such that the application runs solely within your computer’s browser window (most popular browsers are supported). This article discusses the downloadable version, but the mechanics of the program are the same for both versions. The application is copyrighted but freely distributed/used.

The basic recipe for success in using “Snake Measurer” are to start with a good photograph—the best method is to photograph your subject from directly overhead, with a straight-line reference of Fig. 1. Using the “Snake Measurer” application to determine the length of a San Diego banded gecko, Coleonyx variegatus abbotti. This 11-year-old male with regenerated known, measurable length as the background (e.g. surface upon tail is 3.86 inches in total length. Photo by the author. which the animal is crawling). The web site instructions discourage the use of coins as the size reference because it’s difficult to accurately measure the diameter perfectly. Unfortunately, in the past I took photographs from a distance of 12 inches and 36 inches, with that was exactly how I measured my animals. I have since switched focal lengths of 28, 85, 135, 200, 300, 400, and 560mm for each to photographing them on graph paper. distance. I initially used quarters as both my reference objects and target-measurement objects, since I wanted to see just how much After opening the image in “Snake Measurer,” you first define a error I was inducing in my previous measurements of my animals; known distance (for example, if you photographed a lizard on graph those results are not published here since using round objects as paper with ¼-inch squares, you could count out 8 squares and tell the references is not recommended. I also measured the graph paper application the defined item is 2 inches long). Next you start at either as both reference and target in order to analyze how much greater head or tail of the animal, and click points along the spine/centerline the accuracy could be. I primarily hoped to determine what extent until you have measured the entire animal. I prefer starting at the lens distortion contributed to inaccuracies in measurement, and how head because it allows me to record the snout-vent length first, then variations in focal length could potentially reduce those inaccuracies. continue defining points to the tail tip to get the overall length. See Figure 1 (right) for an example of the application in action. For the first experiment—examining the effects of lens distortion—I used a 2-inch length of squares (eight) at the center of each image Assuming you define your reference object’s length accurately, the as a reference object, then compared that length to measurements of program will give you an accurate measurement. The larger your eight squares from the upper-middle, upper-right, and middle-right reference object, the better, since errors in measuring this object extremes of the image. Each set of measurements was accomplished (clicking the end point a few pixels too long or too short) will be three times and the results averaged. The error resulting from these magnified with larger animals. However, I was also curious asto measurements reflects the distortion induced into the measurement the effects of lens distortion and/or the “height” of the animal of objects positioned at the edges of the lens’ field of view. For above the measured object (such as a lizard standing on outstretched the two longest focal lengths, the reference and target measurements legs vs. one resting on the surface). All three types of errors (mis- were reduced to one inch due to field-of-view limitations. measurement of reference object, lens distortion, and disparity between distance of animal and distance of surface) will compound Figure 2 (next page) shows errors in measurement (in percent) for to reduce the accuracy of the animal’s actual length. I am sure there known 2-inch lengths of squares for each portion of the image, SWCHR Bulletin 25 Summer 2013 based on a reference 2-inch length from the center of the image (one Figure 3 (next page) depicts errors in measurement resulted from inch for the 400 and 560mm focal lengths), from a distance of 36 an object being elevated above the reference object, based on the inches. The worst-case average error was less than 6 percent, for the reference object (a 2-inch length of squares in the center of the graph squares in the corner of the viewable image at a focal length image) being adjacent to the target object. The worst errors for of 28mm (the “wide angle” setting, which intuitively was expected both focal lengths tested were from 12 inches above the reference to induce the most lens distortion). As the focal length increased surface but were still 2.5 percent or less. Curiously, both focal lengths (“zooming in” on the target), error significantly decreased. With resulted in the target object appearing smaller than actual size when a 135mm focal length, the worst-case error is for an object in the compared to the reference surface from a distance of 36 inches corner of the frame and even then it is only one percent. In this case, above the reference surface. However, the error was a mere 1.05 using a 135mm focal length seems to provide the best results while percent or less. preserving a useful field of view—roughly the size of an 8.5” x 11” sheet of paper. The second experiment had me curious as to how much greater the apparent size of a measured object might be for longer distances From a distance of 12 inches, only the 28 and 85mm focal lengths between the camera and object of interest, more closely approximating provided a useful field of view comparable to the size of a sheet of the effect of a person holding a snake in front of them. I repeated paper, and the worst-case error for an object in the corner of the the second experiment using the same methodology mechanics, but image as just over 2 percent at the 28mm focal length. substituted an 8.5 x 11 inch sheet of paper for the measured object and placed it one foot above the reference surface and photographed For the second experiment—determining error induced by elevation it from a distance of nine feet above the reference surface. of an object above the reference measurement—I measured the apparent size of a quarter raised one inch above the reference The results (Figure 4, next page) indicate errors in apparent size of surface, using focal lengths of 85 and 135mm, from a distance of approximately 10 percent and 9 percent for 85mm and 135mm focal 12 inches and 36 inches. Similar to the previous experiment, I used lengths, respectively. This essentially indicates a five-foot snake held “Snake Measurer” to measure the quarter images three times each, one foot in front of a person, photographed from nine feet away, then averaged the results. I again based my reference length on the would appear to be five feet, six inches long as measured in “Snake graph paper squares, and the measured diameter of the quarter was Measurer.” compared to the actual diameter of a U.S. quarter (0.955 inches).

Fig. 2. Measurement error (in percent) for a 2-inch length in the top-middle, top-right, and middle-right of the photographic image for focal lengths from 28mm to 300mm, and a 1-inch length for 400 and 560mm focal lengths, from a distance of 36 inches. Error bars represent one standard deviation. SWCHR Bulletin 26 Summer 2013 Conclusions

While the results of my experiments were generally as expected (and intuitive), my goal was to quantify the error. Distortion of the target object increases toward the edges of the image, especially at shorter focal lengths (“wide angle” settings). From my analysis, the best way to minimize error using “Snake Measurer” to measure an object of interest is to keep the object as close to the center as possible, or at least along the vertical axis of the image (if the camera is held in the “normal” horizontal position). Zooming from a longer distance, rather than relying on closer photography to fill the frame, also reduces error. Combining these two techniques should produce measurements with only two percent or less error.

Your results may vary depending on your camera equipment. For my Canon, it appears my best bet is to use an 85mm or 135mm focal length from a distance of 36 inches. This is now how I photograph my captive banded geckos for measurement, and the resultant field of view from this technique is effective for small reptiles such as most native US lizards and small- to medium-size snakes (if coiled).

I initially wanted to determine error induced by elevated target objects, since my geckos often stand on fully-extended limbs as well as wave their tails in the air. After analyzing my results, I now Fig. 3. Measurement error (in percent) for a US quarter in the center of a photographic envision a followup experiment to demonstrate the effects of forced image for focal lengths of 85mm and 135mm, from distances of 12 and 36 inches above the reference surface. Error bars represent one standard deviation. perspective which could be useful in more accurately determining the length of snakes in various photographs on the Internet (purporting to show abnormally-large rattlesnakes, for example). Such an experiment would need to incorporate multiple camera models, so a call for participation in the endeavor may be forthcoming.

Fig. 4. Measurement error (in percent) for an 8.5 x 11 inch sheet of paper in the center of a photographic image for focal lengths of 85mm and 135mm, from a distance of nine feet above the reference surface. Error bars represent one standard deviation. SWCHR Bulletin 27 Summer 2013 Mating Pair of Texas Horned Lizards (Phrynosoma cornutum) on a New Mexico Roadway (Lacertilia: Phrynosomatidae)

by Chris McMartin; Observation by Ron Govreau

During his return trip from the Snake Days 2013 event held in Sanderson, Texas, Ron Govreau observed a pair of Texas horned lizards (Phrynosoma cornutum) mating in the middle of the intersection of State Highways 9 and 81 at the eastern edge of the city of Hachita, Grant County, New Mexico. Upon being approached, the female scrambled but the male remained on her back, apparently not disturbed. Mr. Govreau photographed the pair after they were off the roadway and continued home. Time of the 14 June observation was approximately 7:00 a.m.; air temperature was between 75 and 80 degrees Fahrenheit, skies were clear and there was no wind.

This pair of Texas horned lizards (Phrynosoma cornutum) were discovered mating in the center of a paved highway intersection in southwestern New Mexico. The photograph was taken after they had moved off the roadway; mating behavior continued throughout the observation. Photo by Ron Govreau.

Mating activity of Texas horned lizards in the wild is well-documented both in scientific literature and via naturalist photography available through personal web sites, but a limited literature survey did not reveal any previous record of the species engaging in mating behavior on paved roads. However, several publications did mention the lizards’ propensity for basking on roads and at least one publication suggested dirt roads are used as overnight bedding areas (Henke and Fair, 1998). Given the need for open space in otherwise vegetated habitat in which to thermoregulate (Ibid.), it seems reasonable that time spent on roadways would also regularly include courtship and mating, though it increases exposure to predators and vehicle- induced mortality.

Literature Cited

Henke, Scott E. and Wm. Scott Fair. “Management of Texas Horned Lizards.” Wildlife Management Bulletin of the Caesar Kleberg Wildlife Research Institute, No. 2. Texas A&M University—Kingsville, 1998. SWCHR Bulletin 28 Summer 2013 SWCHR CODE OF ETHICS

As a member of the Southwestern Center for Herpetological Research, I subscribe to the Association’s Code of Ethics.

Field activities should limit the impact on natural habitats, replacing all cover objects, not tearing apart rocks or logs and refraining from the use of gasoline or other toxic materials.

Catch and release coupled with photography and the limited take of non-protected species for personal study or breeding use is permitted. The commercial take and sale of wild-caught animals is not acceptable.

Collecting practices should respect landowner rights, including but not limited to securing permission for land entry and the packing out of all personal trash.

Captive-breeding efforts are recognized as a valid means of potentially reducing collection pressures on wild populations and are encouraged.

The release of captive animals including captive-bred animals into the wild is discouraged except under the supervision of trained professionals and in accordance with an accepted species preservation or restocking plan.

The disclosure of exact locality information on public internet forums is discouraged in most circumstances. Locality information posted on public internet forums usually should be restricted to providing the name of the county where the animal was found. When specific locality data is provided ot one in confidence, it should be keptin confidence and should not be abused or shared with others without explicit permission.

Other members of the Association are always to be treated cordially and in a respectful manner.

SWCHR PO BOX 624 SEGUIN TX 78156