Pub Date : 2016-06-20DOI: 10.1655/HERPMONOGRAPHS-D-15-00004
Brian Folt, J. Jensen, Amber Teare, D. Rostal
Abstract: The conservation of large, long-lived turtle species can be a challenging issue because their life-history strategies make populations sensitive to changes in adult survivorship and populations may be difficult to sample. The Alligator Snapping Turtle (Macrochelys temminckii) is a large freshwater turtle species occurring in North America for which commercial harvest has severely reduced populations throughout the species range. Given recent population declines and a general deficit of demographic knowledge for Macrochelys, we conducted a mark–recapture study of M. temminckii from 1997–2013 in Spring Creek, Georgia, USA. We made 166 captures of 75 individuals using baited hoop-net traps and skin-diving searches. The observed and estimated population structure described the adult sex ratio as even and adults as more abundant than juveniles. Apparent survival was higher for adult males (0.98) and females (0.95) than for juveniles (0.86), and we estimated a population density of 13–14 turtles/stream kilometer. The survival estimates for adult M. temminckii are among the highest of all freshwater turtle species reported in the literature. We used the empirical demographic parameters described here and a literature review to build an updated population model for M. temminckii; the model estimated a finite rate of population increase consistent with a growing population (λ = 1.036) at Spring Creek, and population viability analysis found the population growing over the next 50 yr in 100% of simulations. Application of our model to published survival estimates from two impacted western populations indicated a declining population (λ = 0.563) with a high risk of extirpation in Oklahoma and a population with a slow rate of decline (λ = 0.978) but approaching stability in Arkansas. Simulations identified combinations of survival values which generate viable populations and also characterized population structure resulting from viable scenarios. This is the first study to document a stable and viable population of Macrochelys. We suggest that the population parameters described at Spring Creek are the best approximation of reference demographic conditions for Macrochelys to date, and this study provides a general framework applicable for large, long-lived, endangered turtle species for which demographic data are unavailable.
{"title":"Establishing Reference Demography for Conservation: A Case Study of Macrochelys temminckii in Spring Creek, Georgia","authors":"Brian Folt, J. Jensen, Amber Teare, D. Rostal","doi":"10.1655/HERPMONOGRAPHS-D-15-00004","DOIUrl":"https://doi.org/10.1655/HERPMONOGRAPHS-D-15-00004","url":null,"abstract":"Abstract: The conservation of large, long-lived turtle species can be a challenging issue because their life-history strategies make populations sensitive to changes in adult survivorship and populations may be difficult to sample. The Alligator Snapping Turtle (Macrochelys temminckii) is a large freshwater turtle species occurring in North America for which commercial harvest has severely reduced populations throughout the species range. Given recent population declines and a general deficit of demographic knowledge for Macrochelys, we conducted a mark–recapture study of M. temminckii from 1997–2013 in Spring Creek, Georgia, USA. We made 166 captures of 75 individuals using baited hoop-net traps and skin-diving searches. The observed and estimated population structure described the adult sex ratio as even and adults as more abundant than juveniles. Apparent survival was higher for adult males (0.98) and females (0.95) than for juveniles (0.86), and we estimated a population density of 13–14 turtles/stream kilometer. The survival estimates for adult M. temminckii are among the highest of all freshwater turtle species reported in the literature. We used the empirical demographic parameters described here and a literature review to build an updated population model for M. temminckii; the model estimated a finite rate of population increase consistent with a growing population (λ = 1.036) at Spring Creek, and population viability analysis found the population growing over the next 50 yr in 100% of simulations. Application of our model to published survival estimates from two impacted western populations indicated a declining population (λ = 0.563) with a high risk of extirpation in Oklahoma and a population with a slow rate of decline (λ = 0.978) but approaching stability in Arkansas. Simulations identified combinations of survival values which generate viable populations and also characterized population structure resulting from viable scenarios. This is the first study to document a stable and viable population of Macrochelys. We suggest that the population parameters described at Spring Creek are the best approximation of reference demographic conditions for Macrochelys to date, and this study provides a general framework applicable for large, long-lived, endangered turtle species for which demographic data are unavailable.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2016-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1655/HERPMONOGRAPHS-D-15-00004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67432117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-06-20DOI: 10.1655/HERPMONOGRAPHS-D-14-00009
Paulo Passos, A. Prudente, J. Lynch
Abstract: We redescribe Atractus punctiventris based on the examination of its holotype, two topotypes, and two additional specimens recently collected. We describe two new species of Atractus with 15 dorsal scale rows, previously confused with Atractus insipidus, from the eastern and western portions of Brazilian Amazonia, respectively. The new species are recognized on the basis of unique combinations of morphological characters. We compare Atractus punctiventris and the two new species with all congeners from most lowland provinces of cis-Andean South America. We discuss potential affinities of the three species, mainly by sharing exclusive hemipenial traits with congeners placed in different phenetic groups, and allocate them to distinct species groups of Atractus.
{"title":"Redescription of Atractus punctiventris and Description of Two New Atractus (Serpentes: Dipsadidae) from Brazilian Amazonia","authors":"Paulo Passos, A. Prudente, J. Lynch","doi":"10.1655/HERPMONOGRAPHS-D-14-00009","DOIUrl":"https://doi.org/10.1655/HERPMONOGRAPHS-D-14-00009","url":null,"abstract":"Abstract: We redescribe Atractus punctiventris based on the examination of its holotype, two topotypes, and two additional specimens recently collected. We describe two new species of Atractus with 15 dorsal scale rows, previously confused with Atractus insipidus, from the eastern and western portions of Brazilian Amazonia, respectively. The new species are recognized on the basis of unique combinations of morphological characters. We compare Atractus punctiventris and the two new species with all congeners from most lowland provinces of cis-Andean South America. We discuss potential affinities of the three species, mainly by sharing exclusive hemipenial traits with congeners placed in different phenetic groups, and allocate them to distinct species groups of Atractus.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2016-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1655/HERPMONOGRAPHS-D-14-00009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67432067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper contains a synopsis of the genus Phrynopus in Bolivia, including the description of twelve new species. With seventeen species currently known, the genus has a much higher diversity in Bolivia than previously expected. Whereas intraspecific variation is evident only in color pattern, interspecific variation is noticeable in size, robustness, shape of head, relative lengths of extremities and digits, and skin texture. However, some species are quite similar in appearance and would be difficult to identify in the field were it not for their extremely restricted distributions. The genus Phrynopus has an amazing radiation and its species diversity has been severely underestimated.
{"title":"BOLIVIAN FROGS OF THE GENUS PHRYNOPUS, WITH THE DESCRIPTION OF TWELVE NEW SPECIES (ANURA: BRACHYCEPHALIDAE)","authors":"I. J. De la Riva","doi":"10.1655/07-011.1","DOIUrl":"https://doi.org/10.1655/07-011.1","url":null,"abstract":"This paper contains a synopsis of the genus Phrynopus in Bolivia, including the description of twelve new species. With seventeen species currently known, the genus has a much higher diversity in Bolivia than previously expected. Whereas intraspecific variation is evident only in color pattern, interspecific variation is noticeable in size, robustness, shape of head, relative lengths of extremities and digits, and skin texture. However, some species are quite similar in appearance and would be difficult to identify in the field were it not for their extremely restricted distributions. The genus Phrynopus has an amazing radiation and its species diversity has been severely underestimated.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2007-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1655/07-011.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67431697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The state of ossification of the skeleton at hatching or birth and shortly thereafter is described and compared for 21 squamate species. The presence in the neonate of metapodial ossification centers and epiphyseal secondary centers varies among species, whereas the appearance of apophyseal ossifications and endochondral calcifications and the ossification of sesamoid precur- sors are predominantly postnatal phenomena. The data suggest a possible causal relationship be- tween viviparity and skeletally immature neonates, whereas state of ossification at hatching or birth is probably attributable to phylogeny overall. Of the clades represented in this investigation, phry- nosomatids, teiioids, and amphisbaenians exhibit the most skeletally mature neonates, whereas the reverse is true of gekkotans, xantusiids, and anguids.
{"title":"A SURVEY OF STATE OF OSSIFICATION IN NEONATAL SQUAMATES","authors":"J. Maisano","doi":"10.2307/1467041","DOIUrl":"https://doi.org/10.2307/1467041","url":null,"abstract":"The state of ossification of the skeleton at hatching or birth and shortly thereafter is described and compared for 21 squamate species. The presence in the neonate of metapodial ossification centers and epiphyseal secondary centers varies among species, whereas the appearance of apophyseal ossifications and endochondral calcifications and the ossification of sesamoid precur- sors are predominantly postnatal phenomena. The data suggest a possible causal relationship be- tween viviparity and skeletally immature neonates, whereas state of ossification at hatching or birth is probably attributable to phylogeny overall. Of the clades represented in this investigation, phry- nosomatids, teiioids, and amphisbaenians exhibit the most skeletally mature neonates, whereas the reverse is true of gekkotans, xantusiids, and anguids.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68497213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The eastern ratsnake, Elaphe obsoleta currently includes seven highly variable and taxonomically confusing subspecies. Recently, maximum likelihood and maximum parsimony phy- logenetic analyses of two mitochondrial gene sequences suggested that the complex of E. obsoleta (including E. bairdi) is composed of four distinct evolutionary lineages found in four geographical areas: 1) an eastern clade located east of the Apalachicola River and the Appalachian Mountains, 2) a central clade located west of the Apalachicola River and the Appalachian Mountains and east of the Mississippi River, 3) a western clade located west of the Mississippi River, and 4) E. bairdi is located in southwest Texas and northeastern Mexico. With respect to this phylogeographic hy- pothesis, the former seven subspecies of E. obsoleta do not represent distinct evolutionary lineages. In this paper, the morphology of Elaphe obsoleta and E. bairdi is compared to the results of the previous molecular study. Univariate and multivariate analyses of 67 morphological characters scored from 1006 specimens provided statistical support for the recognition of the same four evolutionary lineages identified in the phylogeographic study. Specimens can be classified morphologically by using canonical discriminant function analysis into the four molecular clades more accurately than they can be grouped into subspecific categories. Moreover, the identification of these subspecies proved difficult when using the traditional characters ascribed to them. In light of the corroborating molecular and morphological evidence, it is suggested that the recognition of the subspecies of E. obsoleta be discontinued. Instead, the four molecular clades should be recognized as four species: 1) eastern clade = E. alleghaniensis, 2) central clade = E. spiloides, 3) western clade = E. obsoleta, and 4) E. bairdi = E. bairdi.
东部鼠蛇，Elaphe obsoleta目前包括七个高度可变和分类混乱的亚种。最近，对两个线粒体基因序列的最大似然和最大简约生理分析表明，E. obsoleta(包括E. bairdi)复合体由四个不同的进化谱系组成，分布在四个地理区域:1)东部分支位于阿巴拉契科拉河和阿巴拉契亚山脉以东，2)中部分支位于阿巴拉契科拉河和阿巴拉契亚山脉以西，密西西比河以东，3)西部分支位于密西西比河以西，4)E. bairdi位于德克萨斯州西南部和墨西哥东北部。根据这一系统地理学假说，前7个亚种并不代表明显的进化谱系。本文比较了大鲵和大鲵的形态特征，并与前人的分子研究结果进行了比较。对1006个标本的67个形态特征进行单因素和多因素分析，为系统地理学研究中确定的相同的四个进化谱系的识别提供了统计支持。使用典型判别函数分析可以更准确地将标本划分为四个分子枝，而不是将它们划分为亚特异性类别。此外，当使用赋予它们的传统性状时，这些亚种的鉴定被证明是困难的。在分子和形态学证据的支持下，我们建议停止对其亚种的识别。相反，这四个分子分支应该被识别为四个物种:1)东部分支= E. alleghaniensis, 2)中部分支= E. spiloides, 3)西部分支= E. obsoleta, 4) E. bairdi = E. bairdi。
{"title":"Systematics of the eastern ratsnake complex (Elaphe obsoleta)","authors":"F. Burbrink","doi":"10.2307/1467037","DOIUrl":"https://doi.org/10.2307/1467037","url":null,"abstract":"The eastern ratsnake, Elaphe obsoleta currently includes seven highly variable and taxonomically confusing subspecies. Recently, maximum likelihood and maximum parsimony phy- logenetic analyses of two mitochondrial gene sequences suggested that the complex of E. obsoleta (including E. bairdi) is composed of four distinct evolutionary lineages found in four geographical areas: 1) an eastern clade located east of the Apalachicola River and the Appalachian Mountains, 2) a central clade located west of the Apalachicola River and the Appalachian Mountains and east of the Mississippi River, 3) a western clade located west of the Mississippi River, and 4) E. bairdi is located in southwest Texas and northeastern Mexico. With respect to this phylogeographic hy- pothesis, the former seven subspecies of E. obsoleta do not represent distinct evolutionary lineages. In this paper, the morphology of Elaphe obsoleta and E. bairdi is compared to the results of the previous molecular study. Univariate and multivariate analyses of 67 morphological characters scored from 1006 specimens provided statistical support for the recognition of the same four evolutionary lineages identified in the phylogeographic study. Specimens can be classified morphologically by using canonical discriminant function analysis into the four molecular clades more accurately than they can be grouped into subspecific categories. Moreover, the identification of these subspecies proved difficult when using the traditional characters ascribed to them. In light of the corroborating molecular and morphological evidence, it is suggested that the recognition of the subspecies of E. obsoleta be discontinued. Instead, the four molecular clades should be recognized as four species: 1) eastern clade = E. alleghaniensis, 2) central clade = E. spiloides, 3) western clade = E. obsoleta, and 4) E. bairdi = E. bairdi.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2001-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467037","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68497252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lecithotrophic (yolk based) nutrition is a well-documented condition for the embryos of oviparous reptiles. However, the continuation of this nutritional state following hatching, here formally defined as postnatal lecithotrophy, has rarely been considered in reptile life history studies or in reptile nutritional strategies. Approximately 50% of the caloric value of yolk lipids may be conserved as a post hatching reserve for both growth and mobility in neonate North American tortoises. A preliminary experiment was designed to study if the metabolic dependence on residual yolk may be quantified and the duration of that dependence delimited. Baseline data from tortoise egg yolk established the lipid components available in the yolk prior to hatching. Analysis of blood plasma identified those lipid components present in adult tortoises, and finally, circulating blood from neonate tortoises was drawn at intervals to monitor the extent to which lipid components abundant in yolk continue to be utilized. Neonate tortoises subsisting on residual yolk had signifi- cantly higher plasma lipids than neonate tortoises that had been fed. All of the lipid fractions including total lipid, triacyl glycerol, phospholipid, cholesterol and cholesterol esters were signifi- cantly higher in fasted than in fed tortoises. Also there were significant differences in some of the individual fatty acids between fed and fasted neonates. Prior observations and inferences suggest that this nutritional stage may continue through the first six months following hatching. It may also be attenuated by a secondary conversion of yolk invested energy into fat. Field observations indicate that lack of rainfall and associated deficits in available forage may make newly emergent neonates in the western and central Mojave Desert almost entirely dependent on such reserves for their first half year of life. Post natal lecithotroph tortoises may be able to emerge into a dry September Mojave Desert landscape, disperse rapidly
{"title":"POST NATAL LECITHOTROPH: A NEW AGE CLASS IN THE ONTOGENY OF REPTILES","authors":"V. Lance, D. J. Morafka","doi":"10.2307/1467040","DOIUrl":"https://doi.org/10.2307/1467040","url":null,"abstract":"Lecithotrophic (yolk based) nutrition is a well-documented condition for the embryos of oviparous reptiles. However, the continuation of this nutritional state following hatching, here formally defined as postnatal lecithotrophy, has rarely been considered in reptile life history studies or in reptile nutritional strategies. Approximately 50% of the caloric value of yolk lipids may be conserved as a post hatching reserve for both growth and mobility in neonate North American tortoises. A preliminary experiment was designed to study if the metabolic dependence on residual yolk may be quantified and the duration of that dependence delimited. Baseline data from tortoise egg yolk established the lipid components available in the yolk prior to hatching. Analysis of blood plasma identified those lipid components present in adult tortoises, and finally, circulating blood from neonate tortoises was drawn at intervals to monitor the extent to which lipid components abundant in yolk continue to be utilized. Neonate tortoises subsisting on residual yolk had signifi- cantly higher plasma lipids than neonate tortoises that had been fed. All of the lipid fractions including total lipid, triacyl glycerol, phospholipid, cholesterol and cholesterol esters were signifi- cantly higher in fasted than in fed tortoises. Also there were significant differences in some of the individual fatty acids between fed and fasted neonates. Prior observations and inferences suggest that this nutritional stage may continue through the first six months following hatching. It may also be attenuated by a secondary conversion of yolk invested energy into fat. Field observations indicate that lack of rainfall and associated deficits in available forage may make newly emergent neonates in the western and central Mojave Desert almost entirely dependent on such reserves for their first half year of life. Post natal lecithotroph tortoises may be able to emerge into a dry September Mojave Desert landscape, disperse rapidly","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467040","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68497119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Plethodontid salamanders of the genus Batrachoseps comprise a clade of morphologically similar, elongate species whose great genetic diversity is being revealed through molecular studies. We used allozymes and mtDNA sequences to study variation in 62 populations from central coastal California, treated most recently as members of the B. pacificus complex. Analyses of mtDNA data identify four lineages that are well differentiated from each other and do not form a monophyletic group. Instead, the central coastal lineages are multiply paraphyletic with respect to the southern California members of the pacificus group. Marked allozymic differences show that these four lineages are strongly differentiated, although some limited gene exchange may have occurred in the past. Each lineage is also morphologically distinctive, but the differences between them are subtle. Because these lineages appear to be evolving independently, we describe them as new species: B. luciae, B. incognitus and B. minor, distributed parapatrically from north to south in the Santa Lucia Mountains of coastal Monterey and San Luis Obispo Counties, and B. gavilanensis, occurring mainly inland from the range of B. luciae, centered on the Gabilan Mountains, but also extending to the Pacific coast at the north end of the range of the complex, along the northern border of Monterey Bay. Although no sympatry is known among any of the new species, B. luciae and B. gavilanensis are narrowly parapatric. Furthermore, all but B. luciae occur in sympatry with other members of the genus in at least a part of their geographic ranges. The new species may have arisen vicariantly with respect both to each other and to related forms in southern California, in part as a result of the dramatic tectonic movements that have characterized the last 15 million years of geological history in western North America.
{"title":"Molecular phylogenetic analysis of slender salamanders genus Batrachoseps (Amphibia: Plethodontidae), from central coastal California with descriptions of four new species","authors":"E. Jockusch, Kay P. Yanev, D. Wake","doi":"10.2307/1467038","DOIUrl":"https://doi.org/10.2307/1467038","url":null,"abstract":"Plethodontid salamanders of the genus Batrachoseps comprise a clade of morphologically similar, elongate species whose great genetic diversity is being revealed through molecular studies. We used allozymes and mtDNA sequences to study variation in 62 populations from central coastal California, treated most recently as members of the B. pacificus complex. Analyses of mtDNA data identify four lineages that are well differentiated from each other and do not form a monophyletic group. Instead, the central coastal lineages are multiply paraphyletic with respect to the southern California members of the pacificus group. Marked allozymic differences show that these four lineages are strongly differentiated, although some limited gene exchange may have occurred in the past. Each lineage is also morphologically distinctive, but the differences between them are subtle. Because these lineages appear to be evolving independently, we describe them as new species: B. luciae, B. incognitus and B. minor, distributed parapatrically from north to south in the Santa Lucia Mountains of coastal Monterey and San Luis Obispo Counties, and B. gavilanensis, occurring mainly inland from the range of B. luciae, centered on the Gabilan Mountains, but also extending to the Pacific coast at the north end of the range of the complex, along the northern border of Monterey Bay. Although no sympatry is known among any of the new species, B. luciae and B. gavilanensis are narrowly parapatric. Furthermore, all but B. luciae occur in sympatry with other members of the genus in at least a part of their geographic ranges. The new species may have arisen vicariantly with respect both to each other and to related forms in southern California, in part as a result of the dramatic tectonic movements that have characterized the last 15 million years of geological history in western North America.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68497314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Wilson, K. Nagy, C. Tracy, D. J. Morafka, R. A. Yates
{"title":"Water Balance in Neonate and Juvenile Desert Tortoises, Gopherus agassizii","authors":"D. Wilson, K. Nagy, C. Tracy, D. J. Morafka, R. A. Yates","doi":"10.2307/1467042","DOIUrl":"https://doi.org/10.2307/1467042","url":null,"abstract":"","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467042","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68497504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The widely distributed Common Gartersnake (Thamnophis sirtalis) thrives in a va- riety of environments and preys upon a diversity of species. Phenotypic plasticity (including learn- ing), as well as genetic diversity, may underlie the success of this species. We examined how different types of feeding experience influence the ontogeny of foraging behavior in garter snakes from two populations with different adult diets (earthworm or amphibian/worm/mammal diets) living on Bea- ver Island in Lake Michigan. Times to approach, capture, handle, and swallow prey were recorded in controlled laboratory settings. In Experiment I, neonatal snakes reared on fish, earthworms, or a mixed diet were tested for feeding skills at their first feeding, and at 5 subsequent intervals after feeding experience and diet-switching over a period of nearly 8 months. Snakes in all three groups decreased their latencies to consume prey after feeding experience and there were some litter, but no site or sex, differences. Snakes fed initially on worms were slow at consuming fish upon diet switching, whereas snakes that initially fed on fish rapidly consumed worms upon their first feeding. Feeding skills for initial prey were retained following the diet-switching phase. Experiment II de- termined the effects of long-term feeding experience on the abilities of field-caught adult snakes to detect, capture, and consume frogs, fish, and worms. Most foraging measures differed for all three prey, but there were few site differences and no sex differences. The effects of prior feeding ex- perience appear to be less evident for adults than for neonates, which may be due to the effects of changing predator-prey body size relationships, changes in prey availability, or to constraints of the captive testing environment. Although populations on the island eat different prey, there is little evidence for genetic differentiation in foraging behavior during the several thousand years that the island has existed.
{"title":"NEONATAL PLASTICITY AND ADULT FORAGING BEHAVIOR IN GARTER SNAKES (THAMNOPHIS SIRTALIS) FROM TWO NEARBY, BUT ECOLOGICALLY DISSIMILAR, HABITATS","authors":"M. Krause, G. Burghardt","doi":"10.2307/1467039","DOIUrl":"https://doi.org/10.2307/1467039","url":null,"abstract":"The widely distributed Common Gartersnake (Thamnophis sirtalis) thrives in a va- riety of environments and preys upon a diversity of species. Phenotypic plasticity (including learn- ing), as well as genetic diversity, may underlie the success of this species. We examined how different types of feeding experience influence the ontogeny of foraging behavior in garter snakes from two populations with different adult diets (earthworm or amphibian/worm/mammal diets) living on Bea- ver Island in Lake Michigan. Times to approach, capture, handle, and swallow prey were recorded in controlled laboratory settings. In Experiment I, neonatal snakes reared on fish, earthworms, or a mixed diet were tested for feeding skills at their first feeding, and at 5 subsequent intervals after feeding experience and diet-switching over a period of nearly 8 months. Snakes in all three groups decreased their latencies to consume prey after feeding experience and there were some litter, but no site or sex, differences. Snakes fed initially on worms were slow at consuming fish upon diet switching, whereas snakes that initially fed on fish rapidly consumed worms upon their first feeding. Feeding skills for initial prey were retained following the diet-switching phase. Experiment II de- termined the effects of long-term feeding experience on the abilities of field-caught adult snakes to detect, capture, and consume frogs, fish, and worms. Most foraging measures differed for all three prey, but there were few site differences and no sex differences. The effects of prior feeding ex- perience appear to be less evident for adults than for neonates, which may be due to the effects of changing predator-prey body size relationships, changes in prey availability, or to constraints of the captive testing environment. Although populations on the island eat different prey, there is little evidence for genetic differentiation in foraging behavior during the several thousand years that the island has existed.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467039","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68497439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Taxonomic reconsideration of Middle American frogs of the Eleutherodactylus rugulosus group (Anura: Leptodactylidae): A reconnaissance of subtle nuances among frogs","authors":"Jonathan A. Campbell, J. Savage","doi":"10.2307/1467048","DOIUrl":"https://doi.org/10.2307/1467048","url":null,"abstract":"","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467048","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68498265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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