Lacerta agilis is a widespread lizard which reaches the western edge of its range in Britain where it is restricted to three geographically separated areas. Recent habitat loss and fragmentation have resulted in a significant decline and it is now a UK conservation priority. Sand lizards from across the Britain were genotyped at 15 microsatellite loci and the resulting dataset used to address questions regarding the conservation genetics, phylogeography and influence of landscape on patterns of genetic diversity. Genetic diversity of Dorset populations compared favourably to European examples. However, diversity was significantly lower in Surrey and Merseyside. Significant genetic structuring occurred across small geographical distances even in relatively unfragmented landscapes. Lacerta agilis colonised Britain via a land bridge across the North Sea and reached the limits of its current distribution approximately 5,000 years BP. Subsequent climate cooling has resulted in a range contraction to areas where the habitat is suitable for the successful incubation of eggs. A resistance surface was used to investigate the effect of landscape configuration on patterns of genetic diversity at multiple scales in Dorset. At a local scale, habitat type and rivers were the best predictors of genetic diversity. At a regional scale, rivers were most important, whereas habitat type and artificial barriers were less important. Artificial barriers may be more significant than the results suggest as their true effect has not yet been realised due to a genetic time-lag. Male lizards from Merseyside exhibited significant differences in colour and pattern to the Dorset and Surrey populations. However, despite difference in colour, all populations were equally green, which is in keeping with the importance of ‘greenness' as a sexual signal. The implications of these findings for the conservation of L. agilis are discussed in the context of current challenges and predicted future global climate change.

In this thesis I have connected different evolutionary studies of Lioalemus lizards. In Chapter 1, I followed an integrative approach to delimit species in the Liolaemus walkeri complex. Using mitochondrial markers, morphological data, bioclimatic information and methods appropriate for each data type, we found that the name L. walkeri was covering three new lineages. Three new species were described and one of them (L. chavin) is now categorized as Near Threatened in the IUCN red list. In Chapter 2, I change the subject from species boundaries to the study of viviparity and placentation. In this paper we employed scanning electron and confocal microscopy to compare the placental ultra-structure and pattern of blood vessels in two Liolaemus species. One of the most remarkable traits found is the complete reduction of the eggshell in both placentae, a possible adaptation to improve gas exchange in the hypoxic environments of the high Andes. In chapter 3, I returned to the issue of species delimitation and employed two integrative approaches: a hypothetical deductive framework and a model-based procedure. I applied both approaches in lowland and highland Liolaemus species of the montanus group. I found that in only one case (of four) an unnamed lowland lineage ("Nazca") was delimited concordantly by both procedures. In Chapter 4, I focus on a study of convergent evolution of desert phenotype in Liolaemus species and Ctenoblepharys adspersa. I performed a Bayesian time calibrated and maximum likelihood tree based on 55 taxa and seven molecular markers. We employed quantitative and categorical traits based on 400 specimens and non-metric multidimensional scaling to obtain new quantitative variables. I used three phylogenetic comparative methods to identify and measure the strength of convergence. My results found a strong case of convergent traits in C. adspersa, L. lentus, L. manueli, L. poconchilensis and L. stolzmanni that are probably related to predator avoidance in the Peruvian-Atacama and Monte deserts. In addition, my time calibrated tree resolves the origin of these traits first in C. adspersa at about 80 million years (My) and later independently in Liolaemus species at about 25 My suggesting the present of evolutionary constraints.

Thermal ecology and movement of the Leopard Lizard, G. wistizeniwere studied at Frog Spring, adjacent to the Alvord Desert, and at various locations throughout the Alvord Basin. Seasonal activity is known to occur from early May to mid-October, but abundance. gradually decreases after late July. During favorable late spring, and summer weather lizards exhibit a bimodal pattern of diel activity with some activity occurring at all hours of the day between 0600 and 1800 H. At other times activity was unimodal. Emergence was apparently largely temperature dependent and did not occur until sand temperature approximated 21°C. Retreat appeared to be temperature independent, and was initiated by exogenous or endogenous stimuli at sand temperatures often above body temperatures acceptable for normal activity. For the period of study, juveniles exhibited diel activity patterns similar to adults, and were found during all hours in which adults were encountered. Body temperatures of field active lizards, largely affected by the immediate weather conditions, , ranged from 18.6° to 43.4°C. Because of a variety of thermoregulatory response (changes in location, posture, and orientation, color change, burrowing, shade-seeking, and panting), even during unfavorable weather conditions, most body temperatures fell within a narrower range. Nonetheless, the ability of field active lizards to precisely thermoregulate was limited, and the levels of body temperature maintained usually encompassed a broader range than those maintained in a thermal gradient. The mean body temperature of field active lizards during favorable weather conditions, and that of active lizards in a thermal gradient, did not differ significantly, and seemed to indicate a narrow range of body temperature preference. However, prevailing weather conditions were frequently unfavorable, thus limiting the extent of time during which selection of preferred body temperature could occur. Consequently, though activity depended on the attainment of certain temperature levels, G. wislizeni was forced to adapt to a broader range of body temperatures when performing most routine tasks. The necessity of precision thermoregulation is unclear, but apparently physiological efficiency was not greatly diminished over the broad range of body temperatures fiefd active lizards were often accepting. Relatively speaking, movement in G. wislizeni was extensive. Adult males occupied an average area more than twice the size of adult females and juveniles. Plotted polygons, constructed from sighting points, tended to be elongate. The extent to which lizards occupied a definite home range was uncertain. Adult males , continuously expanding the area occupied, probably lacked a home range. Adult females, demonstrating . little area expansion, perhaps maintained a home range. Territoriality by means of intraspecific display or aggression appeared negligible in G. wislizeni.Adult males did not demonstrate such behavior toward one another . Based on a limited extent of area overlap, adult females may have exhibited territoriality toward members of their sex. Movement per hour revealed results similar to area occupied, with adult males traveling an average distance of nearly three times as great as adult females and juveniles. Greatest distances frequently coincided with peak diel activity. Individual moves were frequent in adult males and juveniles, but infrequent in ~ adult females. Adult female long moves were similar in distance to adult males, but exogenous stimuli perhaps linked with home range maintenance restricted the frequency of such jaunts. Movement in G. wislizeni appeared independent of environmental thermal conditions when body temperature was within the range acceptable for normal activity. Diel movement appeared to be random in the species. Seasonal movement in juveniles, based on dispersion data, appeared directional.

The conservation of biological diversity has become one of the most important goals of managing forests in an ecologically sustainable way. In this thesis, I report a comprehensive study designed to examine the long-term effects of commercial logging and high-intensity fire, and the ability of Population Viability Analysis (PVA) models to predict these effects to aid in the conservation and management of multiple species. Initially, I compared the abundance of small mammals (A. agilis, R. fuscipes, A. swainsonii), and lizards (L. delicata, L. guichenoti, E. heatwolei), in sites with different disturbance histories: 18-19 yearold logging regrowth, 28-29 or 33-34 year???old clearfelling regrowth and unlogged forest. All sites had previously been burnt by bushfires. No evidence of long-term effects of logging or fire was found for A. agilis, R. fuscipes, L. delicata or L. guichenoti, and there were not enough data to make conclusions for A. swainsonii and E. heatwolei. Then the effects of a hazard-reduction burn were investigated. There was variation between the species in the effects of the burn, with interactions between year, aspect and burning for A. agilis and R. fuscipes, and interactions between year, disturbance and topography for the Lampropholis species. A. swainsonii became extremely scarce in the forest after the burn and E. heatwolei were generally unaffected. Next, PVA metapopulation models were used to predict the likely abundance and patch occupancy of these species based on historical data. Retrospective testing showed the models were accurate for all species, but best for A. agilis and R. fuscipes. Lastly, PVA modelling was used to rank management options; no management action, a hazard-reduction burn in 2005 or a logging event in 2005. The models predicted that future management is likely to result in the extinction of A. agilis, R. fuscipes and L. guichenoti by 2010. However, no one management scenario was most detrimental to all species. The current management regime for this forest involves commercial logging on a 40-year cycle and regular hazard-reduction burning. PVA modelling predicts that A. swainsonii and L. delicata are at the greatest risk of extinction under this regime, but that it is also likely to lead to the extinction of A. agilis, R. fuscipes and L. guichenoti in the near future. The results of this research indicate that the conservation of multiple species under one management regime is unlikely to be successful.

There is a global effort to research the impacts of habitat fragmentation and degradation on wildlife. There is, however, still a need for greater understanding of ecological processes at work in fragmented and degraded habitat in peri-urban and agricultural areas. The study was undertaken in order to enable insights to be gained to provide a basis for management of fragmented habitat, using a single species as a focus. Eastern Bearded Dragon Pogona barbata is a reptile icon in Australia, but which is regarded anecdotally as being in decline, and for which little is known of the ecology. The aim of the study was to research the biology and spatial ecology of a species that had a dependent relationship on structural habitat of the nature of that found in peri-urban areas. Pogona barbata was selected as being an appropriate species in being terrestrial l /arboreal, having a territorial social structure, being an ecological generalist species, and being of a suitable size for study in relation to the size of fragmented habitat in western Sydney. Wild populations in relatively undisturbed habitat in the peri-urban area of western Sydney, Australia, were observed from 2000 to 2002, with additional data gained from museum collections and road-killed animals. Morphometrics were analysed by taking the ratio of a character to snout-vent length, and plotting that value against snout-vent length in order to more clearly see allometric change. Detailed tracking of animals using spool threads was used to collect data on microhabitat use, spatial activity and home range. The distribution of P. barbata across its range coincided with open forest and woodland habitat, which in some areas is subject to intensive urban and agricultural impacts. Pogona barbata is found to be insectivorous as a juvenile and omnivorous as an adult. As hatchlings grow, the relative length of the tail increases (positive allometry) until sexual maturity, and this coincides with an insectivorous diet. The onset of sexual maturity occurs just after the diet becomes omnivorous, and the relative tail length decreases (negative allometry) to a value that can be less than that of hatchlings. The gracile body form of juveniles is different from the robust body form of adults, and this is consistent with the difference in diet and microhabitat use. Factors affecting the persistence of the species were identified. Eggs were eaten by foxes on a regular basis, and hatchlings and juveniles were very rare, indicating an unbalanced demographic structure. The apparent rarity of hatchlings and juveniles may be due to crypsis. Road death was found to remove important breeding individuals from the population. An improved method of estimating testis volumes in lizards using three dimensions was used, which showed that the anatomy of P. barbata testes is bilaterally asymmetrical. It is currently assumed that reptile testes are at least bilaterally regular, but this is not the case in P. barbata. The outcome of this finding is that reproductive and other studies that rely on measurement of a single testis in two dimensions may miss significant data. Testis volumes for P. barbata in western Sydney in the past 20 years are highly abnormal, which coincides with increasing air pollution in the area. Extremes of testis condition were absent testes, very small testes, and extreme differences of testis size in individual animals. Resource partitioning was found, with microhabitat use, to be significantly different for juveniles, males and females. Juveniles and hatchlings used dense habitat with a high incidence of fine and coarse woody debris. The fine matter in the habitat upon which adult females also rely is lost in frequent fires that are used to control bushfire hazard. Pogona barbata is generally regarded as a sit-and-wait predator, on the basis of its being commonly observed on obvious perches. This study demonstrates that such perches are not the most important component of its habitat and that its foraging mode is that of a grazing omnivore. This study appears to be the first that addresses a seasonal shift in microhabitat use for a reptile in general terms. The pattern of daily activity changes with season, and changes in daily habitat preference based on age, sex and season, indicated that P. barbata required a diverse structural habitat. This habitat is affected by frequent hazard reduction fires. A new method of estimating animal home range is presented. The method consists of daily spool trace polygons collected by GPS and analysed in ArcView 3.2, with a spatial analysis output that indicates an estimated total home range and a confidence interval for that estimate. A typical result is an acceptable estimate within 20-30 sequential days of tracking an animal. That outcome is a considerable improvement on the currently accepted minimum of 50 independent days, being at least 100 calendar days. Pogona barbata ‘breaks the rules’ for a number of concepts in the biology of reptiles, and in this study has displayed some new insights in testis morphology, ontology and ecology. It was rare in the areas studied, lending support to the perception that the species is in decline. Reproductive suppression was suspected to affect the population in western Sydney. Pogona barbata has shown a range of characteristics that makes it useful as an umbrella species for the purpose of managing fragmented and degraded habitat in peri-urban and agricultural areas. A range of biological and ecological measures is required to enable effective habitat management of any species, and this study has provided some appropriate techniques for that purpose. / Doctor of Philosophy (PhD)

Thesis (Ph. D.)--University of Oregon, 2002. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 87-99). Also available for download via the World Wide Web; free to University of Oregon users.

No description available.

The conservation of biological diversity has become one of the most important goals of managing forests in an ecologically sustainable way. In this thesis, I report a comprehensive study designed to examine the long-term effects of commercial logging and high-intensity fire, and the ability of Population Viability Analysis (PVA) models to predict these effects to aid in the conservation and management of multiple species. Initially, I compared the abundance of small mammals (A. agilis, R. fuscipes, A. swainsonii), and lizards (L. delicata, L. guichenoti, E. heatwolei), in sites with different disturbance histories: 18-19 yearold logging regrowth, 28-29 or 33-34 year???old clearfelling regrowth and unlogged forest. All sites had previously been burnt by bushfires. No evidence of long-term effects of logging or fire was found for A. agilis, R. fuscipes, L. delicata or L. guichenoti, and there were not enough data to make conclusions for A. swainsonii and E. heatwolei. Then the effects of a hazard-reduction burn were investigated. There was variation between the species in the effects of the burn, with interactions between year, aspect and burning for A. agilis and R. fuscipes, and interactions between year, disturbance and topography for the Lampropholis species. A. swainsonii became extremely scarce in the forest after the burn and E. heatwolei were generally unaffected. Next, PVA metapopulation models were used to predict the likely abundance and patch occupancy of these species based on historical data. Retrospective testing showed the models were accurate for all species, but best for A. agilis and R. fuscipes. Lastly, PVA modelling was used to rank management options; no management action, a hazard-reduction burn in 2005 or a logging event in 2005. The models predicted that future management is likely to result in the extinction of A. agilis, R. fuscipes and L. guichenoti by 2010. However, no one management scenario was most detrimental to all species. The current management regime for this forest involves commercial logging on a 40-year cycle and regular hazard-reduction burning. PVA modelling predicts that A. swainsonii and L. delicata are at the greatest risk of extinction under this regime, but that it is also likely to lead to the extinction of A. agilis, R. fuscipes and L. guichenoti in the near future. The results of this research indicate that the conservation of multiple species under one management regime is unlikely to be successful.

Thesis (Ph.D.)--Edith Cowan University, 2006. / Submitted to the Faculty of Computing, Health and Science. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1955. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 121-123).