Dissertations / Theses on the topic 'Reptiles Snails'

Snake species are notoriously difficult to study in the field due to their cryptic natural-histories and secretive behaviors. Difficulties associated with detection present challenges estimating parameters including occupancy and abundance, as well as responses to habitat degradation. Our objectives were to use Passive Integrated Transponder (PIT) telemetry to enhance detection of Queensnakes (Regina septemvittata) as compared to traditional capture-mark-recapture (CMR) survey techniques and to examine occupancy and abundance of Queensnakes and Northern Watersnakes (Nerodia sipedon) in streams of differing levels of anthropogenic impact within Central Kentucky. During 2013, we captured Queensnakes and implanted them with PIT tags. We detected significantly more tagged snakes using PIT telemetry than visual surveys. We did not observe significant differences in numbers of snakes detected using PIT telemetry at different times of day. We observed relatively high site fidelity of individuals. During 2014, we conducted point-count surveys of Northern Watersnakes and Queensnakes in streams characterized as highly degraded and lightly impaired. We estimated occupancy and conditional abundance among site types. We did not observe significant differences in occupancy or abundance between historically highly-impacted sites and less-impacted sites. We were able to determine significance of some environmental variables influencing detection of snakes.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A diversidade das serpentes é ampla, com aproximadamente três mil espécies descritas. Esta diversidade é agrupada, tanto por evidências morfológicas como moleculares, em dois clados: Alethinophidia (~2660 espécies) e Scolecophidia (~400 espécies). Comparativamente aos Alethinophidia, poucos estudos foram realizados até o momento com Scolecophidia, estudos estes dificultados tanto pelos hábitos furtivos como pela raridade destas serpentes. O clado Scolecophidia é reconhecido por agrupar serpentes pequenas, com olhos vestigiais e hábito subterrâneo. Atualmente são reconhecidas cinco famílias: Anomalepididae, Gerrhopilidae, Leptotyphlopidae, Xenotyphlopidade e Typhlopidae. A família Typhlopidae possui ampla distribuição, ocorrendo em todos os continentes incluindo diversas formações insulares. Dos cinco gêneros que compõem a família, o genêro Typhlops é o mais especioso, com aproximadamente 145 espécies descritas que ocupam uma variedade de hábitats, desde desertos até florestas tropicais. Na América do Sul são reconhecidas oito espécies, sendo Typhlops brongersmianus a espécie que apresenta a maior distribuição, ocorrendo em diversos domínios morfoclimáticos. Em geral, vertebrados com estilo de vida subterrâneo são de difícil observação, e muitos aspectos de sua biologia evolutiva são mal compreendidos, incluindo o modo prevalente de especiação e os padrões de diversificação, bem como a estrutura geográfica da variabilidade genética e morfológica. Sendo assim, este trabalho visa dirimir estas lacunas tendo por objetivo estudar os padrões filogeográficos e demográficos, tentando contribuir para a elucidação da história evolutiva e taxonômica de T. brongersmianus bem como compreender as relações filogenéticas desta espécie com outras congêneres que ocorrem em...
The diversity of snakes is vast, with approximately three thousand described species. This diversity is grouped by both morphological and molecular evidence, in two clades: Alethinophidia (~2660 species) and Scolecophidia (~400 species). Compared to Alethinophidia, few studies have been conducted so far with Scolecophidia, these studies hampered both by furtive habits as the rarity of these snakes. The clade Scolecophidia group is recognized by small snakes with vestigial eyes and subterranean. Currently, five families are recognized: Anomalepididae, Gerrhopilidae, Leptotyphlopidae, and Xenotyphlopidade Typhlopidae. The family Typhlopidae has a wide distribution, occurring in all continents including several island formations. Of the five genera in the family, the genre is the most specious Typhlops, with about 145 described species that occupy a variety of habitats, from deserts to tropical rainforests. In South America are recognized eight species, Typhlops brongersmianus the species with the widest distribution, occurring in various areas morphoclimatic. In general, vertebrates with underground lifestyle are difficult to observe, and many aspects of their evolutionary biology are poorly understood, including the prevalent mode of speciation and diversification patterns and the geographical structure of genetic and morphological variability. Thus, this study aims to resolve these shortcomings have been studying the phylogeographic and demographic patterns, trying to contribute to the elucidation of evolutionary history and taxonomic T. brongersmianus well as understand the phylogenetic relationships of this species with other congeners that occur in sympatry in South America To do this, we performed an extensive analysis of morphological revision through a survey of meristic and morphometric characters, totaling... (Complete abstract click electronic access below)

Orientador: Hussam El Dine Zaher
Coorientador: Sandro Luis Bonatto
Banca: Giovanna Gondim Montingelli
Banca: Nelson Jurandi da Rosa Fagundes
Resumo: A diversidade das serpentes é ampla, com aproximadamente três mil espécies descritas. Esta diversidade é agrupada, tanto por evidências morfológicas como moleculares, em dois clados: Alethinophidia (~2660 espécies) e Scolecophidia (~400 espécies). Comparativamente aos Alethinophidia, poucos estudos foram realizados até o momento com Scolecophidia, estudos estes dificultados tanto pelos hábitos furtivos como pela raridade destas serpentes. O clado Scolecophidia é reconhecido por agrupar serpentes pequenas, com olhos vestigiais e hábito subterrâneo. Atualmente são reconhecidas cinco famílias: Anomalepididae, Gerrhopilidae, Leptotyphlopidae, Xenotyphlopidade e Typhlopidae. A família Typhlopidae possui ampla distribuição, ocorrendo em todos os continentes incluindo diversas formações insulares. Dos cinco gêneros que compõem a família, o genêro Typhlops é o mais especioso, com aproximadamente 145 espécies descritas que ocupam uma variedade de hábitats, desde desertos até florestas tropicais. Na América do Sul são reconhecidas oito espécies, sendo Typhlops brongersmianus a espécie que apresenta a maior distribuição, ocorrendo em diversos domínios morfoclimáticos. Em geral, vertebrados com estilo de vida subterrâneo são de difícil observação, e muitos aspectos de sua biologia evolutiva são mal compreendidos, incluindo o modo prevalente de especiação e os padrões de diversificação, bem como a estrutura geográfica da variabilidade genética e morfológica. Sendo assim, este trabalho visa dirimir estas lacunas tendo por objetivo estudar os padrões filogeográficos e demográficos, tentando contribuir para a elucidação da história evolutiva e taxonômica de T. brongersmianus bem como compreender as relações filogenéticas desta espécie com outras congêneres que ocorrem em... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The diversity of snakes is vast, with approximately three thousand described species. This diversity is grouped by both morphological and molecular evidence, in two clades: Alethinophidia (~2660 species) and Scolecophidia (~400 species). Compared to Alethinophidia, few studies have been conducted so far with Scolecophidia, these studies hampered both by furtive habits as the rarity of these snakes. The clade Scolecophidia group is recognized by small snakes with vestigial eyes and subterranean. Currently, five families are recognized: Anomalepididae, Gerrhopilidae, Leptotyphlopidae, and Xenotyphlopidade Typhlopidae. The family Typhlopidae has a wide distribution, occurring in all continents including several island formations. Of the five genera in the family, the genre is the most specious Typhlops, with about 145 described species that occupy a variety of habitats, from deserts to tropical rainforests. In South America are recognized eight species, Typhlops brongersmianus the species with the widest distribution, occurring in various areas morphoclimatic. In general, vertebrates with underground lifestyle are difficult to observe, and many aspects of their evolutionary biology are poorly understood, including the prevalent mode of speciation and diversification patterns and the geographical structure of genetic and morphological variability. Thus, this study aims to resolve these shortcomings have been studying the phylogeographic and demographic patterns, trying to contribute to the elucidation of evolutionary history and taxonomic T. brongersmianus well as understand the phylogenetic relationships of this species with other congeners that occur in sympatry in South America To do this, we performed an extensive analysis of morphological revision through a survey of meristic and morphometric characters, totaling... (Complete abstract click electronic access below)
Mestre

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
A fam?lia Anomalepididae atualmente ? constitu?da por 18 esp?cies de cobras, conhecidas como ?cobras-cegas?, fossoriais e de distribui??o geogr?fica restrita ? regi?o Neotropical. Praticamente, n?o h? informa??es a respeito da hist?ria de vida dos Anomalepididae, pois s?o animais de dif?cil coleta e a manuten??o em cativeiro para estudos com biologia ? bastante dif?cil. As informa??es dispon?veis a respeito de cobras Anomalepididae est?o concentradas em estudos anat?micos, principalmente osteologia do cr?nio, taxonomia e filogenia a n?vel de fam?lias dentro de Serpentes. Mas, desde a descri??o de Anomalepididae por Taylor em 1939, n?o houve uma revis?o taxon?mica abrangente dentro da fam?lia ou alguma infer?ncia filogen?tica com novos arranjos taxon?micos. Em rela??o ? taxonomia do grupo, a literatura ? restrita ? descri??o de novas esp?cies e revis?es taxon?micas de dois g?neros (Anomalepis e Liotyphlops). O objetivo prim?rio deste estudo foi a revis?o taxon?mica da fam?lia Anomalepididae e, para isto, foi utilizado toda a amostragem poss?vel de esp?cies e esp?cimes na aquisi??o de dados morfol?gicos, al?m do emprego da t?cnica High-Resolution X-ray Computed Tomography (HRXCT). O objetivo secund?rio foi inferir uma hip?tese filogen?tica para as esp?cies dentro de Anomalepididae com base nos caracteres anat?micos obtidos do exame de esp?cimes. Este trabalho resultou em um novo arranjo taxon?mico para Anomalepididae, com 19 esp?cies v?lidas, descri??o de duas novas esp?cies de Liotyphlops para o Brasil, sendo uma para o estado de Mato Grosso e outra para o estado de Santa Catarina e a recondu??o de Liotyphlops beui para a sinon?mia de Liotyphlops ternetzii. Al?m disto, a an?lise de parcim?nia com base em caracteres do cr?nio e da morfologia externa recuperou Anomalepididae como um t?xon monofil?tico dentro de Scolecophidia.
The family Anomalepididae currently consists of 18 species known as "blind snakes", fossorial in habit and with geographical distribution restricted to the Neotropical region. Practically, there is no information about the life history of the Anomalepididae, because they are difficult to collect and the maintenance in captivity for biology studies is quite difficult. The information available regarding Anomalepididae snakes is concentrated on anatomical studies, mainly osteology of the skull, taxonomy, and phylogeny at the level of families within Serpentes. But since the description of Anomalepididae by Taylor in 1939, there has been no comprehensive taxonomic review within the family or some phylogenetic inference with new taxonomic arrangements. In relation to the taxonomy of the group, the literature is restricted to the description of new species and taxonomic revisions of two genera (Anomalepis and Liotyphlops). The primary objective of this study was the taxonomic revision of the Anomalepididae and, for this, all possible sampling of species and specimens were used in the acquisition of morphological data, besides the use of the High-resolution X-Ray Computed Tomography (HRXCT) technique. The secondary objective was to infer a phylogenetic hypothesis for the species within Anomalepididae based on the anatomical characters obtained from the specimen examination. This work resulted in a new taxonomic arrangment for Anomalepididae, with 19 valid species, description of two new species of Liotyphlops from Brazil, being one for the state of Mato Grosso and the other for the state of Santa Catarina, and the re-conduction of Liotyphlops beui to the synonymy of Liotyphlops ternetzii. In addition, the parsimony analysis based on characters from the skull and external morphology recovered Anomalepididae as a monophyletic taxon within Scolecophidia.

BACKGROUND:The extant squamates (>9400 known species of lizards and snakes) are one of the most diverse and conspicuous radiations of terrestrial vertebrates, but no studies have attempted to reconstruct a phylogeny for the group with large-scale taxon sampling. Such an estimate is invaluable for comparative evolutionary studies, and to address their classification. Here, we present the first large-scale phylogenetic estimate for Squamata.RESULTS:The estimated phylogeny contains 4161 species, representing all currently recognized families and subfamilies. The analysis is based on up to 12896 base pairs of sequence data per species (average = 2497 bp) from 12 genes, including seven nuclear loci (BDNF, c-mos, NT3, PDC, R35, RAG-1, and RAG-2), and five mitochondrial genes (12S, 16S, cytochrome b, ND2, and ND4). The tree provides important confirmation for recent estimates of higher-level squamate phylogeny based on molecular data (but with more limited taxon sampling), estimates that are very different from previous morphology-based hypotheses. The tree also includes many relationships that differ from previous molecular estimates and many that differ from traditional taxonomy.CONCLUSIONS:We present a new large-scale phylogeny of squamate reptiles that should be a valuable resource for future comparative studies. We also present a revised classification of squamates at the family and subfamily level to bring the taxonomy more in line with the new phylogenetic hypothesis. This classification includes new, resurrected, and modified subfamilies within gymnophthalmid and scincid lizards, and boid, colubrid, and lamprophiid snakes.

A reprodução é custosa para ambos os sexos, mas a magnitude dos gastos e sua relação com o sucesso reprodutivo diferem entre os gêneros. Os custos reprodutivos são divididos em duas categorias: custos de sobrevivência e custos energéticos. Crotalus durissus possui um ciclo reprodutivo sazonal com cópula ocorrendo no outono e a parturição no final no verão. Os machos competem por fêmeas receptivas. A inferência de custos reprodutivos associados à sobrevivência foi realizada por meio de levantamentos das taxas de atividade entre machos e fêmeas. A variação da quantidade de gordura abdominal e dos substratos energéticos do fígado e dos rins foi avaliada para mensurar o custo energético. Os resultados sugerem que para fêmeas a reprodução exige um alto investimento energético evidenciado pelos maiores níveis de gordura abdominal e de lipídios no fígado durante a fase vitelogênica e o padrão de atividade diferenciada entre machos e fêmeas sugere que a estação reprodutiva embute um custo de sobrevivência maior para os machos.
Reproduction is costly for both sexes, but the magnitude of spending and its relation to reproductive success differ between genders. Reproductive costs are divided into two categories: survival costs and energy costs. Crotalus durissus has a seasonal reproductive cycle with mating occurring in the fall and parturition in late summer. The males compete for receptive females. The inference of survival costs was accomplished through surveys of activity rates between males and females. The variation of the amount of abdominal fat and energy substrates in liver and kidneys was evaluated to measure the energy cost. The results suggest that for females reproduction requires a high energy investment - evidenced by the higher levels of abdominal fat and lipids in the liver during vitellogenic phase and activity patterns differentiated between males and females suggests that the reproductive season embeds a higher cost of survival for males.

A tribo Hydropsini compreende três gêneros de serpentes. Dados alimentares são escassos, mas indicam que as espécies consomem principalmente peixes e secundariamente anfíbios anuros. Os Hydropsini são ovíparos ou vivíparos e o polimorfismo é sugerido para algumas espécies. Entretanto, outros aspectos reprodutivos são desconhecidos para a maioria dessas serpentes. Por outro lado, as relações filogenéticas entre os Hydropsini estão estabelecidas. Este trabalho teve como objetivo caracterizar a reprodução e alimentação de doze espécies dos três gêneros, mapear a evolução e analisar possíveis relações entre a evolução de caracteres morfológicos, reprodutivos e alimentares, utilizando a filogenia disponível. Dados foram obtidos de indivíduos preservados (N = 2.871) de espécies amazônicas (Hydrops spp., Pseudoeryx spp., Helicops hagmanni, H trivittatus, H angulatus, H polylepis), do sudoeste (H leopardinus) e sudeste do Brasil (H carinicaudus, H modestus, H infrataeniatus, H gomesi). Os Hydropsini são especialistas em peixes, porém algumas Helicops (exceto H hagmanni) podem consumir anfíbios e lagartos. Hydrops triangularis e P. plicatilis são especialistas em peixes alongados (Synbranchiformes), Peixes Gymnotiformes, Siluriformes e Perciformes foram dominantes nas dietas de Hy. martii, H polylepis e H hagmanni, respectivamente. Nenhum tipo de presa teve dominância importante nas dietas das demais espécies, porém Perciformes foram consumidos com maior freqüência pela maioria. Esses dados indicam que as espécies diferem quanto ao local de forrageio. Aparentemente, o ancestral da tribo possuía cabeça pequena e dieta composta por Synbranchiformes. A dieta se toma mais ampla e o tamanho da cabeça parece ter aumento no ancestral de Helicops. As presas consumidas por muitas Helicops possuem corpos relativamente mais altos e são mais robustas o que pode explicar alterações no crânio de determinadas espécies. Fêmeas atingem a maturidade com tamanho, relativo ao tamanho médio dos adultos, similar em comparação aos machos. Fêmeas são maiores, possuem maior cabeça, circunferência e cauda mais curta que machos. O menor tamanho dos machos indica que o ritual de combate não deve ocorrer na tribo. Os Hydropsini são ovíparos ou vivíparos e o polimorfismo foi confirmado para H angulatus. A reprodução da maioria das espécies deve ser bienal, já que menos de 50% das fêmeas estavam reprodutivas. Os ciclos das fêmeas são sazonais, exceto para H angulatus. A reprodução das espécies amazônicas ocorre ao longo da estação seca e parte da chuvosa. Ciclos reprodutivos restritos às chuvas ocorrem para as espécies do sudeste e sudoeste. Diferenças nos ciclos das fêmeas podem estar associadas à variação no clima dessas regiões. A espermatogênese pode ser contínua ou sazonal. Os duetos deferentes de muitas espécies estão maiores na seca, sugerindo a ocorrência de cópula nesta estação. A fecundidade e o tamanho dos filhotes, relativos ao tamanho das fêmeas, não diferiu entre serpentes ovíparas e vivíparas. A oviparidade é característica plesiomórfica e a viviparidade pode ter surgido três vezes entre as Helicops. A fecundidade parece aumentar no ancestral do clado (Pseudoeryx, Helicops), o qual é composto por serpentes mais robustas em comparação a Hydrops e a muitos Xenodontinae. Porém, o tamanho dos filhotes tende a diminuir nessas serpentes.
The tribe Hydropsini comprises three genera of snakes. Information on food habits is scarce. However previous data indicate that species feed mainly upon fishes but also eat anurans. The Hydropsini are oviparous or viviparous and the polymorphism is suggested for some species. Other reproductive traits are unknown for most species. On the other hand, the phylogenetic relationships of Hydropsini are established. This study aimed to characterize the reproduction and the feeding habits of twelve species of three genera, hypothesise the evolution of morphological, reproductive and diet characters, as well as probable relationships among these traits. Data were obtained from preserved individuals (N = 2.871) of species from northern (Hydrops sp., Pseudoeryx sp., Helicops hagmanni, H. trivittatus, H. angulatus, H. polylepis), southwestern (H. leopardinus) and southeastern Brazil (H. carinicaudus, H. modestus, H. infrataeniatus, H. gomesi). The Hydropsini feed on fishes, but most Helicops eat also frogs and eventually lizards. Hydrops triangularis and P. plicatilis are specialized on Synbranchiformes fishes. Siluriformes, Perciformes and Gymnotiformes were the dominant item in of H. polylepis, H. hagmanni and Hy. martii, respectively. Other species eat several fishes, but Perciformes were consumed more frequently by most. These data here obtained suggest that the species differ in foraging microhabitat. The ancestor of the tribe probably had small head and diet composed predominantly by Synbranchiformes. The diet became widespread and the size of the head increase in the ancestor of Helicops. The preys consumed by most Helicops are stouter and have higher bodies, which may explain changes in the skull of some species. Females and males attain sexual maturity at similar body size, but adult females are larger. Moreover females have larger head and body circumference, and shorter tail than males. The smaller size of males indicates that the combat behavior should not occur in the tribe. The Hydropsini are oviparous or viviparous and the polymorphism was confirmed to H. angulatus. The reproduction of most species may be biennial, since less than 50% of females were reproductive. The cycles of females are seasonal. At the least H. angulatus, has continuous cycle. The reproduction of the Amazonian species occurs throughout the dry season and part of the rainy season. Cycles restricted mainly to the rainy season occur for species in southeastern and southwestern. Differences in the females cycles may be related to distinct climate in the occurrence areas of the species. The spermatogenesis are continuous or seasonal (restricted to the dry or rainy season). The diameter of deferent ducts of most species are larger in the dry season, suggesting that mating is restricted to this season. The fecundity and size of newborns, relative to the body size of female, was similar among species and did not differ between oviparous and viviparous snakes. The oviparity is plesiomorphic and the viviparity may have arisen at the least three times among Helicops. The fecundity increases in the ancestor of the clade (Pseudoeryx, Helicops), which is stouter than Hydrops and many Xenodontinae. However, the size of newborns tends to decrease in these snakes.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 3 May 2018.
The movement ecology of a species can dictate their survival and success. Animals are motivated to move depending on resource priorities and in turn their movements are influenced by the surrounding environment. Natural habitats are being increasingly disturbed by anthropogenic changes which often creates several implications for the existing wildlife. One of these changes include extensive road networks that may fragment landscapes and increase mortality risks for local fauna. This current and global issue is often researched with the aid of road kill statistics which can create a biased view. My study highlights a more realistic method for understanding how organisms interpret and react to road infrastructure by using the movement patterns of 109 telemetered Puff Adders (Bitis arietans). To assess the effect of roads on these snakes within Dinokeng Game Reserve (Gauteng, South Africa) over eight years, Puff Adder lie-up locations (to the nearest road) and movement paths were analysed. Sex, season, years, and the types of roads within the reserve were included to evaluate the motivation for movement and if roads were inhibiting or aiding movement patterns. Compared to random, Puff Adders were closer too, and crossed roads more often. Males crossed roads more frequently than females and during non-mating season, both sexes were closer to roads. Narrow roads with low levels of traffic were also crossed more often. Overall, the roads in Dinokeng Game Reserve do not inhibit movement and patterns suggest that roads may be advantageous for Puff Adders. Roads appear to be foraging hotspots because of micro habitats created along the verges. However, these positive attributes could result in a potential risk when road usage is intensified by traffic. Understanding how species interact with changes to their environment is essential for appropriate management and mitigation and this study illustrates the necessity for unbiased research to properly evaluate these changes and reactions.
EM2018

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Masters of Science, Johannesburg 2018
The morphology and functionality of surface microornamentation in southern African snakes is well-established in terms of resulting optical effects. Velvet-blackness, a type of optical effect is produced when light incident on a scale is scattered by microornamentation. I tested microornamentation from Bitis arietans dorsal exuvia for these optical effects. Scales were excised from shed skins of B. arietans and sputter coated with 15 nm Gold-Palladium to control the effect of pigment. Spectral intensity (SI) of three scale regions of known micro topography was recorded using spectrophotometry over the visible spectrum only as a measure of reflectivity of the scales. Given that surface roughness (the deviation of a membrane’s surface topography from an ideal surface) is a product of the size of surface asperities and its degree of randomness, the three scale regions in order of decreasing surface roughness were dark (dorsal) scales, pale (dorsal) scales, and ventral scales. Measures of SI on dorsal and ventral scale regions revealed lowest SI on dark dorsal scales and highest on ventral scales. In general, the level of micro-structuring was inversely proportional to SI. To test if optical effects are angle-dependent, I measured differences in SI between normal (90) and oblique (45) angles of incidence. Differences in SI between 90 and 45 were significant for all scale regions which revealed that while microornamentation produces optical effects at both normal and oblique incidence, the effect is greater at 45. Given that SI varies with surface roughness such that dark scales have a lower SI than pale scales, I conclude that scale colour in B. arietans is a product of optical effects created by microornamentation. The optical effect may improve the visual camouflage of B. arietans during ambush. While microornamentation is best known for its optical effects, it may have other functions. I examined the microornamentation in Bitis schneideri (Namaqua Dwarf Adder) using electron microscopy and found small, tooth-like protuberances distributed uniformly across the scales and across all body regions. I measured the distance between adjacent denticles which I 5 compared to the mean dimensions of sand grains from two study sites: Noup, within the distribution of B. schneideri, and Tswalu, outside of it but with significantly smaller grains. The space between denticles is smaller than sand grains from both sites. Due to its physical characteristics, microornamentation in B. schneideri has the potential to restrict sand grains from direct contact with the scale surface. These results suggest that microornamentation can function to shield the integument from sand abrasion in B. schneideri. This study demonstrates specific functions of microornamentation in the ecology of two species of Bitis.
XL2019

Rapid urbanization threatens the survival of native wildlife species worldwide. In order to fully grasp the implications of the ongoing growth of urban areas on biodiversity, conservationists need to be able to quantify the response patterns of a wide range of different species to the expansion of urban and suburban land use. In this study, we set up two road-based transects across gradients of urbanization and habitat loss in the diverse longleaf pine forests of the Sandhills region of North Carolina, USA. With funding provided by the NC Wildlife Resources Commission, we drove the transects repeatedly at night in the field seasons of 2006-2008, tallying all vertebrate animals encountered (live or dead). The first transect (driven in all three years; 75 km long) ran from the urban areas of Southern Pines and Pinehurst down to the remote and relatively pristine habitats associated with the state-owned Sandhills Gamelands. The second transect (driven in 2007 and partially in 2008; 69 km long) began at the terminus of the first transect in the Gamelands, and then stretched down to the urban zones of Hamlet and Rockingham.

A total of 4900 vertebrate animals representing 69 species were observed on or near the road routes after driving a total of 16,625 km. This total includes 592 nightjars (ground-nesting nocturnal birds; e.g. whip-poor-wills) that we heard while driving the transects. In addition, in 2007 we surveyed for the nightjars and for quail (a high-priority game species that also nests on the ground) using 75 point count locations evenly distributed along the northern road route.

Regression tree analysis (a robust, nonparametric technique with minimal assumptions) was used to model the animal observation rates for a given 1 km road segment or point count as a function of various habitat variables measured within corresponding buffer zones for each segment. We also modeled snake and bird encounter rates as a function of mesopredator mammal observations.

Our results reveal that amphibian, snake, and ground-nesting bird observation rates are negatively associated with increasing levels of traffic and impervious surface. Conversely, mesopredator mammals (and domestic cats in particular) responded slightly positively to increasing urbanization, and negatively to protected area coverage. Both ground-nesting birds and snakes showed signs of negative correlations with mesopredator encounter rates, although these trends were not always significant due to high variability in the mesopredator data.

In order to try and confirm the results of the regression tree analyses, we also used a multivariate ordination approach (non-metric multidimensional scaling) to visualize the integrated community structure of all of the major vertebrate groups we observed in the Sandhills. The ordinations revealed that while the snake, ground-nesting bird, and amphibian groups were similar to each other in terms of their avoidance of urban conditions, the cats and native mesopredator species actually seemed to define widely divergent axes of community variation. Cats in particular were separated from the other groups on 2 out of 3 axes of the species-space ordination. Still, as we noted above for the regression tree models, it is difficult to sort out with our correlative data set whether cats and other mesopredators truly played an independent role in structuring and/or depleting the other wildlife guilds along our route. More experimental approaches are recommended for trying to resolve whether overabundant predators or road mortality and inappropriate habitat are more to blame for the much reduced encounter rates we observed for the snakes, birds, and amphibians in urban areas. Future studies will also be needed to confirm the logical assumption that road encounter rates provide a reasonably accurate index of the relative abundance of the different animal groups along the survey routes.

Dissertation

The illegal reptile trade quandary in the Western Cape province is strategically and chronologically addressed in this thesis with the implicit intention of revealing its gamut and underlying dynamics, developing a pragmatic, parsimonious and authentic conservation crime category with clearly delineated parameters, and formulating an integrated theoretical explanation regarding its aetiology that will adequately explicate herpetological, and hopefully also other forms of natural resource, crime and deviance. The thesis, by essentially transcending traditional, stereotypical edicts, throws new light on a severely neglected and underestimated form of natural resource exploitation, highlighting the need for reptiles, as the sentinels of the state of our environmental health to be preserved and perpetuated for, in the final analysis, the benefit of human kind. Through an essentially explorative enquiry, utilising an integrated qualitative -quantitative research approach, the concept of conservation crime, as a vanguard to an innovative and unified conservation criminology, is introduced in this thesis in the form of unambiguous adjunct of the mainstream criminological discipline. It is, furthermore, utilised as a conduit within the herpetological crime framework to enrich the criminological discipline as a whole, broaden its frontiers, promote effective and focussed intervention/mitigation initiatives, as well as stimulate interest for further investigation in this field. Fragmented, antiquated and nebulous legislation, deficient conservation and related role-player organisational capacity and inconsistent penalties, in concert with apathetic (and decidedly generic) societal attitudes and traditional pessimistic rubric regarding reptiles, emerge as fundamental proclivities impeding the effective intercession and management of the natural resources embodied in this sphere. Injudicious manipulation of the Western Cape's scarce and specialised reptile resources and the biodiversity ramifications such exploitation realises portend the intensification and diversification potential of such criminality. Conservation criminology, as developed and presented in this thesis, underscores the significant contribution this field of criminology can make in comprehending the illegal manipulation/exploitation of herpetological and other natural resources, expanding and enhancing its theoretical constructs and implementing justice through decisive, dedicated and holistic intervention programmes/strategies in order to defend the inherent right to the continued existence of all reptile species.
Crimonology
D. Litt et Phil. (Criminology)

This study constitutes the first evolutionary investigation of the snake family Psammophiidae—the most widespread, most clearly defined, yet perhaps the taxonomically most problematic of Africa's familylevel snake lineages. Little is known of psammophiid evolutionary relationships, and the type genus Psammophis is one of the largest and taxonomically most complex of the African snake genera. Our aims were to reconstruct psammophiid phylogenetic relationships and to improve characterisation of species boundaries in problematic Psammophis species complexes. We used approximately 2500 bases of DNA sequence from the mitochondrial and nuclear genomes, and 114 terminals covering all psammophiid genera and incorporating approximately 75% of recognised species and subspecies. Phylogenetic reconstructions were conducted primarily in a Bayesian framework and we used the Wiens/Penkrot protocol to aid species delimitation. Rhamphiophis is diphyletic, with Rhamphiophis acutus emerging sister to Psammophylax. Consequently we transfer the three subspecies of Rhamphiophis acutus to the genus Psammophylax. The monotypic genus Dipsina is sister to Psammophis. The two species of Dromophis occupy divergent positions deeply nested within Psammophis, and we therefore relegate Dromophis to the synonymy of Psammophis. Our results allow division of the taxonomically problematic Psammophis 'sibilans' species complex into two monophyletic entities, provisionally named the 'phillipsii' and 'subtaeniatus' complexes. Within these two clades we found support for the status of many existing species, but not for a distinction between P.p. phillipsii and P. mossambicus. Additionally, P. cf. phillipsii occidentalis deserves species status as the sister taxon of P. brevirostris.