Pub Date : 2022-09-06DOI: 10.1655/0018-0831-78.3.221
The Herpetologists’ League is pleased to announce that the recipient of the 2022 Award for Distinguished Service to Herpetology is Dr. Patrick T. Gregory, of the University of Victoria, in British Columbia, Canada. Currently a Professor Emeritus of Biology, Pat Gregory has not only pursued a distinguished career in research, teaching, and mentorship that has spanned nearly 50 years, but he has served the herpetological community through his involvement in many major service roles. Pat Gregory was born in England and moved to Canada when he was seven years old. He received his BSc from the University of Toronto and his MSc and PhD from the University of Manitoba. He was hired immediately out of graduate school by the University of Victoria, where he remained on the faculty for 45 years, serving as Chair for a number of years and officially retiring in 2018. In retirement Pat remains active in research, especially working on data he gathered in a number of extended field studies. As a researcher, Pat has focused particularly on the ecology and conservation of amphibians and reptiles of western Canada, and he is especially recognized for his work on the ecology of natricine snakes, in both North America and Europe. He has worked extensively on their hibernation ecology, thermal relations, and interspecific interactions, including his important work on the natural history of reptiles at high latitudes and his pioneering work at the immense garter snake hibernacula in Manitoba. Pat’s research productivity has been prodigious, with 93 peer-reviewed journal articles, eight book chapters and contributions to proceedings, 13 published book reviews, and 44 other contributions, such as reports to agencies and summaries from working groups. Pat has mentored 26 graduate students, and he has taught courses primarily in the areas of ecology and vertebrate biology. His research has been extensively supported by extramural grants, including 15 prestigious NSERC awards and numerous grants supporting conservation-related activities. He has given countless presentations at conferences and institutions, and he has been actively engaged in outreach to promote the appreciation and conservation of snakes. His research contributions have been recognized many times, as with the Herpetologists’ League Distinguished Herpetologist Award, the Henry S. Fitch Award for Excellence in Herpetology from the American Society of Ichthyologists and Herpetologists (ASIH), and the Michael Rankin Distinguished Canadian Herpetologist Award from the Canadian Herpetological Society (CHS). Similarly, Pat has been recognized for his contributions to the conservation of herpetofauna, receiving the Blue Racer Award from the Canadian Amphibian and Conservation Network and serving as Honorary Professor of Herpetological Conservation at the University of Kent (UK) for 11 years. This year’s Award for Distinguished Service to Herpetology especially recognizes Pat for the breadth of his service on be
爬虫学家联盟很高兴地宣布,2022年爬虫学杰出服务奖的获得者是加拿大不列颠哥伦比亚省维多利亚大学的帕特里克·t·格雷戈里博士。帕特·格雷戈里目前是生物学名誉教授,他不仅在研究、教学和指导方面追求了近50年的杰出职业生涯,而且还通过参与许多主要的服务角色为爬行动物界服务。帕特·格雷戈里出生于英国,七岁时移居加拿大。他在多伦多大学获得理学学士学位,在马尼托巴大学获得理学硕士和博士学位。他在维多利亚大学(University of Victoria)研究生毕业后立即被聘用,在那里任教了45年,担任了多年的主席,并于2018年正式退休。退休后,帕特仍然积极从事研究,特别是对他在许多扩展的实地研究中收集的数据进行研究。作为一名研究人员,帕特特别关注加拿大西部两栖动物和爬行动物的生态学和保护,他在北美和欧洲的蛇毒生态学方面的工作尤其得到认可。他对它们的冬眠生态学、热关系和种间相互作用进行了广泛的研究,包括他在高纬度爬行动物自然史方面的重要工作,以及他在马尼托巴省巨大的袜带蛇冬眠方面的开创性工作。帕特的研究成果是惊人的,有93篇同行评议的期刊文章,8个书籍章节和对会议的贡献,13篇出版的书评,以及44篇其他贡献,如向机构报告和工作组总结。帕特已经指导了26名研究生,他主要教授生态学和脊椎动物生物学领域的课程。他的研究得到了校外资助的广泛支持,包括15个著名的NSERC奖和许多支持保护相关活动的资助。他在会议和机构上做过无数次演讲,他一直积极参与推广欣赏和保护蛇的活动。他的研究贡献多次获得认可,如爬虫学家联盟杰出爬虫学家奖,美国鱼类学和爬虫学家协会(ASIH)的Henry S. Fitch卓越爬虫学奖,以及加拿大爬虫学会(CHS)的Michael Rankin杰出加拿大爬虫学家奖。同样,帕特在保护爬行动物方面的贡献也得到了认可,他获得了加拿大两栖动物和保护网络颁发的蓝色赛车奖,并在英国肯特大学担任了11年的爬行动物保护荣誉教授。今年的爬行动物杰出服务奖特别表彰了帕特代表更广泛的爬行动物界的广泛服务,他在多个专业学会中发挥了领导和服务作用,并主持了几次大型爬行动物会议。Pat提供了广泛的委员会服务,最著名的是ASIH,该协会授予他罗伯特·k·约翰逊奖,以表彰他在理事会工作的19年,在长期规划委员会工作的7年,在执行委员会工作的8年。然而,帕特也曾在爬行动物学家联盟(HL;包括爬行动物杰出服务奖评选委员会主席),两栖动物和爬行动物研究学会(SSAR)董事会成员,以及世界爬行动物大会国际爬行动物委员会成员。最值得注意的是,Pat曾担任多个爬行动物学会的主席,包括ASIH、加拿大爬行动物学家协会和CHS(作为创始联合主席)。除了这些重要的社会办公室,帕特还主持了两个主要的国际会议(以及许多较小的会议)。第一次,他在他的家乡维多利亚大学共同主持了1986年的ASIH年会。第二次,他主持了2012年在温哥华英属哥伦比亚大学举行的第七届世界爬虫学大会(作为组委会主席)。该会议还包括HL、特别行政区和ASIH的年度会议。此外,帕特还在国家和国际会议上组织或共同组织了五次专题讨论会。如果没有帕特个人的热情、他对同事和学生的鼓励以及他迷人的幽默感,那么帕特对我们学科的贡献就不完整。他广泛的专业成就记录不仅证明了他的高水平的精力,也证明了他热情欢迎同事进入他的科学和个人圈子。 在他漫长的职业生涯中,帕特·格雷戈里通过与同事、学生和我们的专业协会的长期积极参与,为爬行动物学领域服务。爬虫学家联盟荣幸地授予我们的同事帕特里克·t·格雷戈里今年的爬虫学杰出服务奖。Patrick T. Gregory在2018年与一只大型雌性条纹草蛇(Natrix helvetica)在英国肯特郡的长期野外基地合影。Linda Gregory摄。
{"title":"Herpetologists' League Award for Distinguished Service to Herpetology","authors":"","doi":"10.1655/0018-0831-78.3.221","DOIUrl":"https://doi.org/10.1655/0018-0831-78.3.221","url":null,"abstract":"The Herpetologists’ League is pleased to announce that the recipient of the 2022 Award for Distinguished Service to Herpetology is Dr. Patrick T. Gregory, of the University of Victoria, in British Columbia, Canada. Currently a Professor Emeritus of Biology, Pat Gregory has not only pursued a distinguished career in research, teaching, and mentorship that has spanned nearly 50 years, but he has served the herpetological community through his involvement in many major service roles. Pat Gregory was born in England and moved to Canada when he was seven years old. He received his BSc from the University of Toronto and his MSc and PhD from the University of Manitoba. He was hired immediately out of graduate school by the University of Victoria, where he remained on the faculty for 45 years, serving as Chair for a number of years and officially retiring in 2018. In retirement Pat remains active in research, especially working on data he gathered in a number of extended field studies. As a researcher, Pat has focused particularly on the ecology and conservation of amphibians and reptiles of western Canada, and he is especially recognized for his work on the ecology of natricine snakes, in both North America and Europe. He has worked extensively on their hibernation ecology, thermal relations, and interspecific interactions, including his important work on the natural history of reptiles at high latitudes and his pioneering work at the immense garter snake hibernacula in Manitoba. Pat’s research productivity has been prodigious, with 93 peer-reviewed journal articles, eight book chapters and contributions to proceedings, 13 published book reviews, and 44 other contributions, such as reports to agencies and summaries from working groups. Pat has mentored 26 graduate students, and he has taught courses primarily in the areas of ecology and vertebrate biology. His research has been extensively supported by extramural grants, including 15 prestigious NSERC awards and numerous grants supporting conservation-related activities. He has given countless presentations at conferences and institutions, and he has been actively engaged in outreach to promote the appreciation and conservation of snakes. His research contributions have been recognized many times, as with the Herpetologists’ League Distinguished Herpetologist Award, the Henry S. Fitch Award for Excellence in Herpetology from the American Society of Ichthyologists and Herpetologists (ASIH), and the Michael Rankin Distinguished Canadian Herpetologist Award from the Canadian Herpetological Society (CHS). Similarly, Pat has been recognized for his contributions to the conservation of herpetofauna, receiving the Blue Racer Award from the Canadian Amphibian and Conservation Network and serving as Honorary Professor of Herpetological Conservation at the University of Kent (UK) for 11 years. This year’s Award for Distinguished Service to Herpetology especially recognizes Pat for the breadth of his service on be","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"221 - 221"},"PeriodicalIF":2.4,"publicationDate":"2022-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43844642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-06DOI: 10.1655/0018-0831-78.3.222
{"title":"E.E. Williams Research GrantCall for Applications","authors":"","doi":"10.1655/0018-0831-78.3.222","DOIUrl":"https://doi.org/10.1655/0018-0831-78.3.222","url":null,"abstract":"","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":" 528","pages":"222 - 222"},"PeriodicalIF":2.4,"publicationDate":"2022-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41251928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-06DOI: 10.1655/Herpetologica-D-21-00030.1
S. J. Weaver, H. Edwards, Tess McIntyre, S. M. Temple, Quinton Alexander, Matthew C. Behrens, Reilly E. Biedebach, S. S. Budwal, Jacqueline E. Carlson, J. O. Castagnoli, Ashley D. Fundingsland, Dashiell V. Hart, Jenna S. Heaphy, Spencer W. Keller, Karisma I. Lucatero, Kai H. Mills, Nikki M. Moallemi, Andrea M. Murguia, Leonardo Navarro, Eli O'Brien, Julia K. Perez, Thomas J. Schauerman, Dylan M. Stephens, Mia C. Venturini, Christine M. White, E. Taylor
Abstract: As the climate crisis continues to alter temperature regimes and water availability, studying how animals regulate water balance grows in importance. We studied variation in water loss across the skin among body regions and its plasticity in response to humidity acclimation in Western Fence Lizards (Sceloporus occidentalis). We examined the effects of climatic and physiological variables on cutaneous evaporative water loss (CEWL) and compared CEWL rates among body regions (dorsum, ventrum, head, dewlap, and mite patch). The best model to explain baseline variation in log-transformed CEWL included: body region; lizard mass; ambient temperature, vapor pressure deficit (VPD), and solar radiation at the time of capture; body temperature, ambient temperature, and VPD at the time of CEWL measurement; and the interactions between body region and each of mass and VPD at the time of capture. These results demonstrate cutaneous osmoregulatory variability among lizards based on climate and body size and within individual lizards based on body region. We also tested CEWL plasticity in response to humidity acclimation. Lizards exposed to humid conditions for 8 d exhibited increased CEWL, and lizards exposed to dry conditions exhibited decreased CEWL compared to initial measurements. This is evidence for rapid and significant acclimatory responses of CEWL in response to changes in environmental humidity. Such variation and plasticity suggest that lizards possess a certain degree of ability for using osmoregulatory changes to respond to climate change.
{"title":"Cutaneous Evaporative Water Loss in Lizards is Variable across Body Regions and Plastic in Response to Humidity","authors":"S. J. Weaver, H. Edwards, Tess McIntyre, S. M. Temple, Quinton Alexander, Matthew C. Behrens, Reilly E. Biedebach, S. S. Budwal, Jacqueline E. Carlson, J. O. Castagnoli, Ashley D. Fundingsland, Dashiell V. Hart, Jenna S. Heaphy, Spencer W. Keller, Karisma I. Lucatero, Kai H. Mills, Nikki M. Moallemi, Andrea M. Murguia, Leonardo Navarro, Eli O'Brien, Julia K. Perez, Thomas J. Schauerman, Dylan M. Stephens, Mia C. Venturini, Christine M. White, E. Taylor","doi":"10.1655/Herpetologica-D-21-00030.1","DOIUrl":"https://doi.org/10.1655/Herpetologica-D-21-00030.1","url":null,"abstract":"Abstract: As the climate crisis continues to alter temperature regimes and water availability, studying how animals regulate water balance grows in importance. We studied variation in water loss across the skin among body regions and its plasticity in response to humidity acclimation in Western Fence Lizards (Sceloporus occidentalis). We examined the effects of climatic and physiological variables on cutaneous evaporative water loss (CEWL) and compared CEWL rates among body regions (dorsum, ventrum, head, dewlap, and mite patch). The best model to explain baseline variation in log-transformed CEWL included: body region; lizard mass; ambient temperature, vapor pressure deficit (VPD), and solar radiation at the time of capture; body temperature, ambient temperature, and VPD at the time of CEWL measurement; and the interactions between body region and each of mass and VPD at the time of capture. These results demonstrate cutaneous osmoregulatory variability among lizards based on climate and body size and within individual lizards based on body region. We also tested CEWL plasticity in response to humidity acclimation. Lizards exposed to humid conditions for 8 d exhibited increased CEWL, and lizards exposed to dry conditions exhibited decreased CEWL compared to initial measurements. This is evidence for rapid and significant acclimatory responses of CEWL in response to changes in environmental humidity. Such variation and plasticity suggest that lizards possess a certain degree of ability for using osmoregulatory changes to respond to climate change.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"169 - 183"},"PeriodicalIF":2.4,"publicationDate":"2022-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43053356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/Herpetologica-D-21-00032
Cory M. Trowbridge, J. Litzgus
Abstract: Anurans exhibit altered chorusing behaviors in response to anthropogenic noise, yet no studies have considered the effects of wind farm presence on anuran chorusing behaviors. We studied amphibian communities in a wind farm situated in a landscape that includes relatively pristine wetlands and forests. We measured amphibian diversity in habitats adjacent to wetlands using transect surveys, and we quantified anuran chorus and call characteristics (diversity, frequency, and duration) using nightly audio recordings in replicated turbine sites (<0.5 km from turbines) and control sites (>1.5 km from turbines). If wind farms present a source of disturbance, then we expected wetlands near turbines to have lower species diversity, lower chorus intensity, and altered call characteristics. We found significantly lower chorus diversity in turbine-site recordings, but no differences in biodiversity between turbine and control sites based on animals captured during transect surveys. Call characteristics did not differ between control and turbine sites; however, frogs calling in the wind farm displayed call characteristics similar to those of frogs calling near noisy roads within control sites, and some anuran species were notably absent from turbine sites. Identification of new threats, including those resulting from putatively green energy alternatives, is essential to mitigating global amphibian decline.
{"title":"Wind Farms Alter Amphibian Community Diversity and Chorusing Behavior","authors":"Cory M. Trowbridge, J. Litzgus","doi":"10.1655/Herpetologica-D-21-00032","DOIUrl":"https://doi.org/10.1655/Herpetologica-D-21-00032","url":null,"abstract":"Abstract: Anurans exhibit altered chorusing behaviors in response to anthropogenic noise, yet no studies have considered the effects of wind farm presence on anuran chorusing behaviors. We studied amphibian communities in a wind farm situated in a landscape that includes relatively pristine wetlands and forests. We measured amphibian diversity in habitats adjacent to wetlands using transect surveys, and we quantified anuran chorus and call characteristics (diversity, frequency, and duration) using nightly audio recordings in replicated turbine sites (<0.5 km from turbines) and control sites (>1.5 km from turbines). If wind farms present a source of disturbance, then we expected wetlands near turbines to have lower species diversity, lower chorus intensity, and altered call characteristics. We found significantly lower chorus diversity in turbine-site recordings, but no differences in biodiversity between turbine and control sites based on animals captured during transect surveys. Call characteristics did not differ between control and turbine sites; however, frogs calling in the wind farm displayed call characteristics similar to those of frogs calling near noisy roads within control sites, and some anuran species were notably absent from turbine sites. Identification of new threats, including those resulting from putatively green energy alternatives, is essential to mitigating global amphibian decline.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"75 - 85"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47726185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/HERPETOLOGICA-D-20-00020
Timothy A. Clay, M. Gifford
Abstract: How organisms respond to abiotic conditions is paramount for predicting their response to climate change. Mechanistic models have been used extensively to predict the distribution and abundance of many organisms based on their physiology and behaviors. To provide further support for, and inform, mechanistic model predictions, relatively realistic laboratory experiments can be created to replicate natural climatic scenarios. We designed enclosures for terrestrial salamanders that allowed for manipulation of abiotic conditions in a relatively realistic way and for observation of both surface and subsurface behaviors. During a trial, enclosures provided realistic conditions that were an accurate reflection of the field conditions that our study species would be exposed to during their active season. Salamanders behaviorally responded to changing abiotic conditions in our enclosures in a similar fashion to what has been observed through long-term field studies. Our study also documented differences in subsurface behavior, with younger and smaller salamanders occupying shallower depths in response to days since feeding. Given the strong correlation between laboratory and field behaviors under current climatic scenarios, as well as the potentially unknown outcomes between abiotic and biotic conditions, we recommend using realistic laboratory enclosures to replicate future climatic conditions to further refine the predictive power of mechanistic models.
{"title":"Behavioral Response to Simulated Environmental Conditions in a Montane Salamander","authors":"Timothy A. Clay, M. Gifford","doi":"10.1655/HERPETOLOGICA-D-20-00020","DOIUrl":"https://doi.org/10.1655/HERPETOLOGICA-D-20-00020","url":null,"abstract":"Abstract: How organisms respond to abiotic conditions is paramount for predicting their response to climate change. Mechanistic models have been used extensively to predict the distribution and abundance of many organisms based on their physiology and behaviors. To provide further support for, and inform, mechanistic model predictions, relatively realistic laboratory experiments can be created to replicate natural climatic scenarios. We designed enclosures for terrestrial salamanders that allowed for manipulation of abiotic conditions in a relatively realistic way and for observation of both surface and subsurface behaviors. During a trial, enclosures provided realistic conditions that were an accurate reflection of the field conditions that our study species would be exposed to during their active season. Salamanders behaviorally responded to changing abiotic conditions in our enclosures in a similar fashion to what has been observed through long-term field studies. Our study also documented differences in subsurface behavior, with younger and smaller salamanders occupying shallower depths in response to days since feeding. Given the strong correlation between laboratory and field behaviors under current climatic scenarios, as well as the potentially unknown outcomes between abiotic and biotic conditions, we recommend using realistic laboratory enclosures to replicate future climatic conditions to further refine the predictive power of mechanistic models.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"86 - 92"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47188427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/Herpetologica-D-21-00009
J. Emerson, Dominic L. Desantis, Vicente Mata-Silva, A. Wagler, Jerry D. Johnson
Abstract: Despite its wide distribution throughout the northern Chihuahuan Desert, extraordinarily little is known about the ecology or behavior of Eastern Black-tailed Rattlesnakes (Crotalus ornatus). The primary literature for Black-tailed Rattlesnakes was largely based on research conducted on the former conspecific (C. molossus); thus, the revalidation of C. ornatus widened the void in our understanding of the species. The aim of this study was to elucidate movement patterns, home range size, and habitat use by C. ornatus in the northern Chihuahuan Desert of far West Texas. Radiotelemetry was used to monitor individual snakes for at least one active season (March–October) from May 2015 through August 2018. Mean (±1 SE) home range size for all individuals was 22.84 ± 4.49 ha and mean daily distance moved was 9.28 ± 0.93 m/d. Male snakes had larger home range sizes, larger core use areas, and greater daily distance moved than did female snakes. On a monthly basis, male movement peaked in August and female movement was statistically similar throughout the active season. Multinomial logit models were used to analyze habitat use patterns of C. ornatus, while controlling for snake, habitat availability, and season. Despite limited availability within snake home ranges, most observations of snakes occurred in arroyos or on rocky slopes. Microhabitat was also used nonrandomly, with snakes seeking cover in rocky refugia or under dense vegetation, rather than in areas containing high proportions of gravel or plant litter. This study presents the first detailed information about habitat and microhabitat use, along with patterns of movement and home range size for the recently revalidated C. ornatus.
{"title":"Movement, Home Range Size, and Habitat Use of Eastern Black-Tailed Rattlesnakes (Crotalus ornatus) in the Northern Chihuahuan Desert","authors":"J. Emerson, Dominic L. Desantis, Vicente Mata-Silva, A. Wagler, Jerry D. Johnson","doi":"10.1655/Herpetologica-D-21-00009","DOIUrl":"https://doi.org/10.1655/Herpetologica-D-21-00009","url":null,"abstract":"Abstract: Despite its wide distribution throughout the northern Chihuahuan Desert, extraordinarily little is known about the ecology or behavior of Eastern Black-tailed Rattlesnakes (Crotalus ornatus). The primary literature for Black-tailed Rattlesnakes was largely based on research conducted on the former conspecific (C. molossus); thus, the revalidation of C. ornatus widened the void in our understanding of the species. The aim of this study was to elucidate movement patterns, home range size, and habitat use by C. ornatus in the northern Chihuahuan Desert of far West Texas. Radiotelemetry was used to monitor individual snakes for at least one active season (March–October) from May 2015 through August 2018. Mean (±1 SE) home range size for all individuals was 22.84 ± 4.49 ha and mean daily distance moved was 9.28 ± 0.93 m/d. Male snakes had larger home range sizes, larger core use areas, and greater daily distance moved than did female snakes. On a monthly basis, male movement peaked in August and female movement was statistically similar throughout the active season. Multinomial logit models were used to analyze habitat use patterns of C. ornatus, while controlling for snake, habitat availability, and season. Despite limited availability within snake home ranges, most observations of snakes occurred in arroyos or on rocky slopes. Microhabitat was also used nonrandomly, with snakes seeking cover in rocky refugia or under dense vegetation, rather than in areas containing high proportions of gravel or plant litter. This study presents the first detailed information about habitat and microhabitat use, along with patterns of movement and home range size for the recently revalidated C. ornatus.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"110 - 118"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47391195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/Herpetologica-D-21-00024
Cord B. Eversole, S. Henke
Abstract: Habitat characteristics can have large effects on nest site selection of oviparous vertebrates. It is thought that habitat preference in many species is driven by natural selection because of habitat-specific fitness consequences. However, long-term studies on nesting of oviparous reptiles, in particular, are less common in comparison with other nesting vertebrates. As a result, specific habitat associations that define nesting habitat for many species are largely unknown. We studied habitat characteristics and selection of American Alligator (Alligator mississippiensis) nest sites in inland freshwater wetlands. We investigated the habitat characteristics associated with 112 nests studied during the 2013–2019 nesting seasons, and quantified habitat characteristics in relation to nest locations and random points. A nearest neighbor analysis indicated that American Alligator nests are not randomly distributed across wetlands, but are more representative of a clumped spatial distribution, suggestive of habitat preference and site selection. We measured habitat variables such as wetland vegetation cover, average water depth, island density, bank slope, canopy cover, and wet bulb globe temperature, as well as alligator population demographics such as relative adult proportion, at each nest and random site. Subsequently, we found that the best variables for predicting American Alligator nest site selection included island density, slope of bank, canopy cover, and wet bulb globe temperature. The best predictive model demonstrated that the odds of nest site selection increased with increasing canopy cover, wet bulb globe temperature, island density, and decreasing bank slope. These habitat choices presumably reduce the risk of nest predation and provide thermal cover for proper balance of nest site microclimate. Based on our results, practices focused on alligator nesting habitat should consider these specific habitat characteristics in outlining applied strategies and working toward management and conservation goals.
{"title":"Wetland Habitat Characteristics Predict Nest Site Selection of American Alligators (Alligator mississippiensis) in an Inland Freshwater Ecosystem","authors":"Cord B. Eversole, S. Henke","doi":"10.1655/Herpetologica-D-21-00024","DOIUrl":"https://doi.org/10.1655/Herpetologica-D-21-00024","url":null,"abstract":"Abstract: Habitat characteristics can have large effects on nest site selection of oviparous vertebrates. It is thought that habitat preference in many species is driven by natural selection because of habitat-specific fitness consequences. However, long-term studies on nesting of oviparous reptiles, in particular, are less common in comparison with other nesting vertebrates. As a result, specific habitat associations that define nesting habitat for many species are largely unknown. We studied habitat characteristics and selection of American Alligator (Alligator mississippiensis) nest sites in inland freshwater wetlands. We investigated the habitat characteristics associated with 112 nests studied during the 2013–2019 nesting seasons, and quantified habitat characteristics in relation to nest locations and random points. A nearest neighbor analysis indicated that American Alligator nests are not randomly distributed across wetlands, but are more representative of a clumped spatial distribution, suggestive of habitat preference and site selection. We measured habitat variables such as wetland vegetation cover, average water depth, island density, bank slope, canopy cover, and wet bulb globe temperature, as well as alligator population demographics such as relative adult proportion, at each nest and random site. Subsequently, we found that the best variables for predicting American Alligator nest site selection included island density, slope of bank, canopy cover, and wet bulb globe temperature. The best predictive model demonstrated that the odds of nest site selection increased with increasing canopy cover, wet bulb globe temperature, island density, and decreasing bank slope. These habitat choices presumably reduce the risk of nest predation and provide thermal cover for proper balance of nest site microclimate. Based on our results, practices focused on alligator nesting habitat should consider these specific habitat characteristics in outlining applied strategies and working toward management and conservation goals.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"133 - 138"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47996531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/HERPETOLOGICA-D-21-00023
A. Durso, Troy J. Kieran, T. Glenn, S. J. Mullin
Abstract: Wild animal diets are challenging to quantify, and the various methods for doing so have strengths and weaknesses. Combining multiple methods can allow ecologists to assess their level of confidence in particular results, increase sample size, and investigate diet over varying time scales. The biases of traditional gut content–based methods are mostly well understood. Newer methods may have important biases that can only be worked out through comparison to established ones. We collected data on the diet of wild Plains Hog-nosed Snakes (Heterodon nasicus) using multiple, fundamentally dissimilar methods, combined analytically using a Bayesian framework to describe an ontogenetic dietary shift. Gut contents were the most straightforward, but yielded a small sample size that fell below any reasonable threshold for making generalizations. Stable isotopes indicated an obvious ontogenetic dietary shift, but were labor-intensive, and conclusions are limited by multiple methodological caveats including similarity among prey groups, maternal carryover effects, and uncertainty in trophic enrichment factors. Fecal environmental DNA (eDNA) was intermediate in terms of effort, yielding results congruent with the other two methods, but the interpretation of which would likely have been confounded by contaminants had we not used all three methods in tandem. Several apparent artifacts are discussed. There are some reassuring similarities among methods. There are also several differences. The most complete picture uses data from all methods taken together. Future studies should attempt to compare the biases, expense, and potential drawbacks of these and other methods in greater detail.
{"title":"Comparison of Three Methods for Measuring Dietary Composition of Plains Hog-nosed Snakes","authors":"A. Durso, Troy J. Kieran, T. Glenn, S. J. Mullin","doi":"10.1655/HERPETOLOGICA-D-21-00023","DOIUrl":"https://doi.org/10.1655/HERPETOLOGICA-D-21-00023","url":null,"abstract":"Abstract: Wild animal diets are challenging to quantify, and the various methods for doing so have strengths and weaknesses. Combining multiple methods can allow ecologists to assess their level of confidence in particular results, increase sample size, and investigate diet over varying time scales. The biases of traditional gut content–based methods are mostly well understood. Newer methods may have important biases that can only be worked out through comparison to established ones. We collected data on the diet of wild Plains Hog-nosed Snakes (Heterodon nasicus) using multiple, fundamentally dissimilar methods, combined analytically using a Bayesian framework to describe an ontogenetic dietary shift. Gut contents were the most straightforward, but yielded a small sample size that fell below any reasonable threshold for making generalizations. Stable isotopes indicated an obvious ontogenetic dietary shift, but were labor-intensive, and conclusions are limited by multiple methodological caveats including similarity among prey groups, maternal carryover effects, and uncertainty in trophic enrichment factors. Fecal environmental DNA (eDNA) was intermediate in terms of effort, yielding results congruent with the other two methods, but the interpretation of which would likely have been confounded by contaminants had we not used all three methods in tandem. Several apparent artifacts are discussed. There are some reassuring similarities among methods. There are also several differences. The most complete picture uses data from all methods taken together. Future studies should attempt to compare the biases, expense, and potential drawbacks of these and other methods in greater detail.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"119 - 132"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43820228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/Herpetologica-D-20-00058
Emilio Mancero, C. Valle, J. Rowe, J. Moore, D. L. Clark
Abstract: Intrasexual selection through male competition favoring larger male body size is the preferred explanation for the evolution and maintenance of male-biased sexual size dimorphism among polygynous species. Although sexual selection has been well studied in some groups of lizards, sexual selection in the nine species of lava lizards (Microlophus spp.) of the Galápagos has received little attention. The purpose of this research was to test the importance of male body size in the context of sexual selection by both sexes. Using three different sizes of robotic models capable of emulating the appearance and display patterns of male San Cristóbal Lava Lizards (M. bivittatus), we analyzed the responses that the models elicited among free-ranging lizards of the same sex (confrontation) and opposite sex (courtship). Results showed that body size of both male lizards and robotic antagonists influenced the number of displays performed by males. Male body size positively influenced the number of aggressive responses, scaling with the size of the opponent. The model representing larger lizards received higher display counts from males. Body size of robotic models, but not female lizards, influenced the number of displays performed by females. Females responded the most to the small and large models. Display intensity was not affected by any of the variables considered for either sex. Results from this study support the hypothesis that male-biased sexual size dimorphism in M. bivittatus is driven at least in part by both intrasexual and intersexual selection favoring larger male body size.
{"title":"Sexual Selection in San Cristóbal Lava Lizards (Microlophus bivittatus): A Test of Male Body Size Using Lizard Robots","authors":"Emilio Mancero, C. Valle, J. Rowe, J. Moore, D. L. Clark","doi":"10.1655/Herpetologica-D-20-00058","DOIUrl":"https://doi.org/10.1655/Herpetologica-D-20-00058","url":null,"abstract":"Abstract: Intrasexual selection through male competition favoring larger male body size is the preferred explanation for the evolution and maintenance of male-biased sexual size dimorphism among polygynous species. Although sexual selection has been well studied in some groups of lizards, sexual selection in the nine species of lava lizards (Microlophus spp.) of the Galápagos has received little attention. The purpose of this research was to test the importance of male body size in the context of sexual selection by both sexes. Using three different sizes of robotic models capable of emulating the appearance and display patterns of male San Cristóbal Lava Lizards (M. bivittatus), we analyzed the responses that the models elicited among free-ranging lizards of the same sex (confrontation) and opposite sex (courtship). Results showed that body size of both male lizards and robotic antagonists influenced the number of displays performed by males. Male body size positively influenced the number of aggressive responses, scaling with the size of the opponent. The model representing larger lizards received higher display counts from males. Body size of robotic models, but not female lizards, influenced the number of displays performed by females. Females responded the most to the small and large models. Display intensity was not affected by any of the variables considered for either sex. Results from this study support the hypothesis that male-biased sexual size dimorphism in M. bivittatus is driven at least in part by both intrasexual and intersexual selection favoring larger male body size.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"93 - 101"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43415441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-17DOI: 10.1655/Herpetologica-D-21-00022
J. Haney, J. Veech, I. Castro-Arellano, S. Fritts
Abstract: Contraction in the geographic range of Texas Horned Lizards (Phrynosoma cornutum) has long been suspected but not definitively examined. Contraction of a species' geographic range occurs through extirpation of local populations and thus might often be an early warning sign of further endangerment of the species. As such, there is a need to identify species distributional databases and develop statistical procedures for testing for range contraction. We developed a method based on regression and data randomization and then applied the method to museum (VertNet) and citizen-science (iNaturalist) data compiled for Texas Horned Lizards spanning the time period 1960–2019. The regression analysis examined whether distances between observations and the range center had decreased or increased over time. Decreases in distances could indirectly indicate range contraction, whereas increases could indicate range expansion. We conducted separate regressions for the four directional quadrants to assess the directionality of range change. Distance to VertNet observations in the eastern and western quadrants declined (P < 0.05) between 1960 and 2019, at rates of 4.4 and 1.5 km per year, respectively. The iNaturalist data (2000–2019) did not reveal significant declines in any of the quadrants. Further analyses indicated that these results were generally robust to the exact estimation (placement) of the historic range center. Our analysis provides the first quantitative assessment and test of contraction in the range of P. cornutum. Our method also demonstrates the utility of using museum and citizen-science data to monitor spatial distribution in other species that may be undergoing range contraction, although analyses must recognize inherent limitations of the data.
{"title":"Museum and Citizen-Science Data Indicate Contraction in the Range of Texas Horned Lizards (Phrynosoma cornutum)","authors":"J. Haney, J. Veech, I. Castro-Arellano, S. Fritts","doi":"10.1655/Herpetologica-D-21-00022","DOIUrl":"https://doi.org/10.1655/Herpetologica-D-21-00022","url":null,"abstract":"Abstract: Contraction in the geographic range of Texas Horned Lizards (Phrynosoma cornutum) has long been suspected but not definitively examined. Contraction of a species' geographic range occurs through extirpation of local populations and thus might often be an early warning sign of further endangerment of the species. As such, there is a need to identify species distributional databases and develop statistical procedures for testing for range contraction. We developed a method based on regression and data randomization and then applied the method to museum (VertNet) and citizen-science (iNaturalist) data compiled for Texas Horned Lizards spanning the time period 1960–2019. The regression analysis examined whether distances between observations and the range center had decreased or increased over time. Decreases in distances could indirectly indicate range contraction, whereas increases could indicate range expansion. We conducted separate regressions for the four directional quadrants to assess the directionality of range change. Distance to VertNet observations in the eastern and western quadrants declined (P < 0.05) between 1960 and 2019, at rates of 4.4 and 1.5 km per year, respectively. The iNaturalist data (2000–2019) did not reveal significant declines in any of the quadrants. Further analyses indicated that these results were generally robust to the exact estimation (placement) of the historic range center. Our analysis provides the first quantitative assessment and test of contraction in the range of P. cornutum. Our method also demonstrates the utility of using museum and citizen-science data to monitor spatial distribution in other species that may be undergoing range contraction, although analyses must recognize inherent limitations of the data.","PeriodicalId":56312,"journal":{"name":"Herpetologica","volume":"78 1","pages":"102 - 109"},"PeriodicalIF":2.4,"publicationDate":"2022-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47325902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}