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Forested shoreline is important perching habitat for bald eagles (Haliaeetus leucocephalus). Bald eagles hunt, feed and loaf on shoreline perches. I measured trees suitable for bald eagle perches along the northern Chesapeake Bay during 1990-1991 to determine the influence of shoreline perch tree availability on bald eagle distribution. The shoreline was divided into 250 x 50 m segments. A segment was considered used if at least 1 eagle had perched on it during 1985-1992. I determined the number of suitable shoreline perch trees, percent forest cover, and distance from the water to the nearest suitable perch tree for each segment. Segments along the Chesapeake Bay had an average of 1 suitable perch tree per 10 m of shoreline. Shoreline segments used by eagles had more suitable perch trees (P = 0.0008) and a larger percent of forest cover (P = 0.0008). Suitable trees on segments with eagle use were closer to water than suitable trees on segments without eagle use (P = 0.0087). The differences in segments with and without eagle use appear to be largely due to the lack of trees in marshes which were used only seldomly. Marsh had few suitable perch trees, less forest cover and a greater mean distance from water to the nearest suitable perch tree than the other land types (P < 0.0001). These factors are unfavorable for foraging eagles and most marsh segments (66.7%) were unused, probably for this reason. The number of suitable perch trees and the percent of forest cover were lower on developed areas than undeveloped, forested areas (P < 0.01 for both tests). Also the distance from water to the nearest suitable perch tree was greater on developed land than forested land (P < 0.01). Thus, development appears to decrease the availability of suitable shoreline perch trees when compared to forested areas. Logistic regression models were created to predict the probability of eagle use, given the conditions at the time of this study. Varying values of development density, percent forest cover, number of suitable perch trees and distance from water to the nearest suitable tree were inputs used in these models to create curves to predict eagle use under different conditions. These curves indicated that, for a given development density, the probability of eagle use increased as the number of suitable perch trees or percent forest cover on the segment increased. Also, for a given development density, the probably of eagle use increases as the distance to water decreases. / Master of Science

Call number: LD2668 .T4 1960 P65

Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: The aim of this study was to investigate the phylogeographic structuring of the honey badger, Mellivora capensis, a highly mobile medium sized carnivore with an extensive distribution throughout sub-Saharan Africa extending into the Middle East and India. Particular focus was placed on providing preliminary data potentially useful for the development of translocation policies for this species in southern Africa. Where possible, genetic results were also compared with current trinomial designations to determine whether subspecies status given to geographical groupings was supported by the genetic data. Mitochondrial control region sequence data was obtained for most a selection of specimen’s available while nuclear microsatellite variation was determined for a subset of individuals where there were sufficient sample sizes available. Phylogeographic structuring of the maternal mitochondrial lineage was initially obscured by the coamplification of a closely related numt. To overcome co-amplification, the numt was identified and mtDNA specific primers were designed. Mitochondrial DNA results are based on the most variable 230 bp of the control region (sequenced for 78 individuals) while five polymorphic nuclear microsatellite markers were scored (for 55 individuals). Analysis, employing both nuclear and mitochondrial data, showed that although a pattern of isolation by distance can be detected, there was evidence for the presence of phylogeographic structuring between eastern and southern Africa. This could be interpreted as due to vicariance, probably associated by rifting and climatic occilations during the Pleistocene. Analyses support the identification of distinct management units for eastern and southern African populations although some evidence exists for secondary introgression between these two regions. Following this, we recommend that translocations between these broad geographic areas should be avoided. Within these geographic areas, because of a general pattern of isolation by distance, we recommend that individuals for translocations come from geographically proximate populations. In some instances, phylogeographic structuring is concordant with subspecies designations but additional sampling will be needed to make any firm taxonomic conclusions. / AFRIKAANSE OPSOMMING: Die doelwit van hierdie studie was om die filogeografiese struktuur van die ratel, Mellivora capensis, ‘n hoogs bewegende medium groot karnivoor met ‘n wydverspreide distribusie deur sub-Sahara Afrika wat strek tot in die Midde Ooste en India, te bepaal. Spesifieke fokus is geplaas op die voorsiening van preliminêre data potensieel bruikbaar vir dir ontwikkeling van verplasing strategieë vir hierdie spesie in suidelike Afrika. Genetiese resultate is, waar moontlik, vergelyk met huidige drieledige kategorieë om te bepaal of subspesies ondersteun word deur die genetiese data. Mitochondriale ‘control region’ DNS volgorde data was verkry vir die meeste van die monsters beskikbaar en kern mikrosatelliet variasie was bepaal vir ‘n gedeelte van individue waar voldoende monster groottes beskikbaar was. Filogeografiese strukturering van die materne mitochondriale merker was oorspronklik versteek deur die ko-amplifikasie van ‘n naby verwante ‘numt’. Om die ko-amplifikasie te oorkom is die ‘numt’ geïdentifiseer en mtDNS spesifieke voorvoerders is ontwerp. Mitochondriale DNS resultate is gebaseer op die mees veranderlike 230 bp van die ‘control region’ (waar die DNS volgorde vir 78 individue bepaal is) en vyf polimorfiese kern mikrosatelliet merkers (in 55 individue). Analises, wat gebruik maak van kern en mitochondriale data, toon wel ‘n patroon van isolasie deur afstand, maar ook ‘n duidelike sigbare filogeograpfiese strukturering tussen oostelike en suidelike Afrika. Hierdie is geïnterpreteer as vikariansie, heel waarskynlik ge-assosieer deur berg verskuiwings en klimaatsveranderinge deur die Pleistocene. Analises ondersteun die identifikasie van definitiewe verkillende bestuurseenhede vir oostelike en suidelike Afrika maar sekere bewyse bestaan dat sekondêre introgressie tussen streke bestaan. Dit word aanbeveel dat translokasies tussen hierdie geografiese areas voorkom moet word. Binne geografiese areas, as gevolg van ‘n algemene patroon van isolasie deur afstand, is dit aanbeveel dat individue vir verplasing van nabygeleë populasies moet wees. In sommige gevalle het filogeografiese strukturering ooreen gestem met subspesies kategorieë, maar verdere materiaal is nodig voor definitiewe taksonomiese besluite geneem kan word.

The waters off the west coast of Scotland have one of the highest densities of harbour porpoise (Phocoena phocoena) in Europe. Harbour porpoise are listed under Annex II of the EU Habitats Directive, requiring the designation of Special Areas of Conservation (SACs) for the species’ protection and conservation. The main aim of this thesis is to identify habitat preferences for harbour porpoise, and key regions that embody these preferences, which could therefore be suitable as SACs; and to determine how harbour porpoise use these regions over time and space. Designed visual and acoustic line-transect surveys were conducted between 2003 and 2008. Generalised Estimating Equations (GEEs) were used to determine relationships between the relative density of harbour porpoise and temporally and spatially variable oceanographic covariates. Predictive models showed that depth, slope, distance to land and spring tidal range were all important in explaining porpoise distribution. There were also significant temporal variations in habitat use. However, whilst some variation was observed among years and months, consistent preferences for water depths between 50 and 150 m and highly sloped regions were observed across the temporal models. Predicted surfaces revealed a consistent inshore distribution for the species throughout the west coast of Scotland. Regional models revealed similar habitat preferences to the full-extent models, and indicated that the Small Isles and Sound of Jura were the most consistently important regions for harbour porpoise, and that these regions could be suitable as SACs. The impacts of seal scarers on distribution and habitat use were also investigated, and there were indications that these devices have the potential to displace harbour porpoise. These results should be considered in the assessment of sites for SAC designation, and in implementing appropriate conservation measures for harbour porpoise.

Maned wolves are endangered carnivores endemic to Brazil. This research aimed to compare the attitudes of interest groups towards the conservation of the maned wolf in urban and rural areas; to investigate how such attitudes may influence the maned wolf's status and conservation; and to recommend ways to incorporate such knowledge into strategies to conserve both wolf and habitat. The methodology used questionnaires and interviews. Questionnaires targeted people living in the neighbourhood of conservation areas, staff and students (year 8 and sixth-form) of local schools; staff and visitors to conservation areas and zoos in three main research locations: Greater São Paulo, the Low Mogiana region and São Carlos city. Other conservation areas and zoos within the São Paulo state contributed further data. The relationship between socio-demographic factors and attitudes towards the maned wolf conservation was also investigated to identify the most positive and negative profiles of respondents. Overall, results indicate a lack of antagonism between urban and rural populations. Results suggest that negative attitudes towards the maned wolf related to: misconceptions about feeding habits and to a lack of clear differentiation between the maned wolf and Canis lupus; perceptions of threat connected to the presence of the maned wolf on people's properties; and possibly values undermining local wildlife. Results, however, consistently indicated local people's tolerance towards the species and towards occasional predation events. Results also indicate discrepancies existing between bio/education professionals' expectations of local people's attitudes and the actual attitudes displayed by the latter. Recommendations addressed misconceptions and values regarding the maned wolf, inclusion of the local community and their issues, and relationships between interest groups for the benefit of maned wolf conservation. The positive attitudes of a majority towards the maned wolf suggest they may support actions favourable to the species and maintain their position in case of conflict. However, further investigation is advised into local people's awareness of the causes of the decline of the maned wolf and of how their behaviour may affect populations of wolves.

published_or_final_version / Biological Sciences / Master / Master of Philosophy

A study of the Helminthoglyptidae of Sonora was undertaken to determine the extent of their distribution and speciation. As a result, nine new species of Sonorella are described, and new ranges of the known species are given. The status of the family is reviewed and its standing is supported with the analysis of morphological characteristics of several genera. The zoogeography of the family and its distribution are shown. Possible dispersal and isolation mechanisms are discussed in order to explain the present distribution of these snails, and comments on ecological and speciation accounts are offered.

Leaf area index (LAI), defined as the one sided green leaf area per unit ground area, is a key parameter in ecosystem process models. Owing to the large area of the earth's surface that they occupy, savanna ecosystems represent the third largest terrestrial carbon sink. There is considerable uncertainty however, as to the functioning of these ecosystems, particularly as they respond to land cover changes. Consequently, ecosystem process models constitute one of the best methods available for investigating the effect this may have on terrestrial carbon cycling. If these models are to be used over large areas however, they need to be parameterised. This thesis develops a methodology to estimate LAI in savanna ecosystems, using remotely sensed earth observation (EO) data, laboratory bidirectional reflectance measurements (BRDF), physically based canopy reflectance models (CRMs), and artificial neural networks (ANN). First, the scattering behaviour of Kalahari soils was characterised, by making laboratory BRDF measurements. Soils were shown to be highly non-Lambertian. These measurements were then used to parameterise three different CRMs. Modelled reflectances were assessed with respect to Landsat ETM+ and Terra-MODIS reflectances. Results showed that a 1-D turbid medium provided the closest fit to the measurements. A series of model sensitivity analyses (SA) were performed, and it was shown that reflectance in the red and shortwave infrared displayed greatest sensitivity to LAI, sensitivity in the near-infrared was negligible. Model inversions were performed with ANN and different waveband combinations, and LAI was estimated. The results showed that LAI could be estimated with high accuracy, an RMSE of 0.3 1, and 0.18, from ETM+ and MODIS measurements, respectively. These results were promising, and with further improvements to models, coupled with more accurate input data, will see the use of EO data play an increasingly important role in understanding the functioning of these savanna ecosystems.

Investigations into the supply, settlement and recruitment of the barnacle Semibalanus balanoides (L.) to shores in Fife, East Scotland were undertaken over three consecutive years (2004 – 2006). Several designs of a passive larval trap, based on earlier published designs, were employed to quantify the delivery (supply) of cyprids to the substratum. Pump samples from the water column were collected to provide a measure of intertidal cyprid concentration. Cyprid concentration was found to exhibit both spatial and temporal variation, but was also found to be significantly correlated with cyprid supply, as quantified by the traps. In some years, pump and trap samples suggested that cyprid abundance in the intertidal was mediated by wind-driven processes. An artificial substratum was used to quantify cyprid settlement, allowing investigations into the supply-settlement relationship. Supply and settlement were found to be two very distinct biological phases. Supply describes the flux of larvae to the substratum. Settlement provides a measure of the amount of larvae that decide to settle on the substratum, as initial attachment for barnacle larvae is not permanent. Whilst supply saturation is unfeasible, daily saturation of the substratum by settlers was observed at many sites along the Fife coast. Levels of settlement saturation were found to vary both temporally, between years, and spatially, over scales of km. Varying levels of the desperation of larvae to settle, mediated by dwindling energy reserves, was thought to explain some of this variation. The supply data also provided some evidence of the possible movement of cyprids along the Fife coast from Fife Ness to Tentsmuir. However, wind-induced transport may also play a dominant role on the Fife coast. A comparison of supply and recruitment of larvae into adult populations revealed that both pre- and post-settlement events may influence recruitment. The relative importance of these factors was shown to be density-dependent. Negative intraspecific interactions were only seen in denser aggregations of adults. In less crowded aggregations, recruitment reflected initial patterns of larval supply.