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Estuaries are among the most productive and diverse of aquatic habitats supporting a rich variety of plants and animals. They are nursery areas for many species of fish harvested by recreational and subsistence anglers. The Swartkops River Estuary (SRE) is situated approximately 10 km north-east of Port Elizabeth and the only major well-preserved estuary within a city, thus unique to South Africa. The SRE is surrounded by highly urbanized and industrialized regions in the Eastern Cape. The aim of this study was to determine and interpret the presence, levels, and distribution of selected priority pollutants in the food web of the SRE. Different components within the SRE were analysed for the presence of environmental contaminants. Seven sites were selected, some coinciding with previous studies in the SRE. Three of these sites are major discharge points that discharge directly into the estuary. Sediment, mud prawn, sand gobies, bird eggs, and various fish species were analysed. Samples were collected in the middle and lower reaches of the estuary, the areas known to receive major pollution loads from neighbouring sources. Heavy metals found in the sediments were compared to previous studies. Bottom sediments and organisms surrounding major discharge points showed higher concentrations of pollutants and compared to previous studies, these concentrations seem to be increasing. Due to biomagnification, higher concentrations were generally found in the top predators although certain elements did not show this trend. Some heavy metal concentrations found in the fish exceeded of the food guidelines and may in turn pose a threat for subsistence users of the SRE. There are indications of multiple different pollution sources. Bird eggs had detectable quantities of polychlorinated biphenyls, but its implications need more investigation. / MSc (Zoology), North-West University, Potchefstroom Campus, 2014

Estuaries are among the most productive and diverse of aquatic habitats supporting a rich variety of plants and animals. They are nursery areas for many species of fish harvested by recreational and subsistence anglers. The Swartkops River Estuary (SRE) is situated approximately 10 km north-east of Port Elizabeth and the only major well-preserved estuary within a city, thus unique to South Africa. The SRE is surrounded by highly urbanized and industrialized regions in the Eastern Cape. The aim of this study was to determine and interpret the presence, levels, and distribution of selected priority pollutants in the food web of the SRE. Different components within the SRE were analysed for the presence of environmental contaminants. Seven sites were selected, some coinciding with previous studies in the SRE. Three of these sites are major discharge points that discharge directly into the estuary. Sediment, mud prawn, sand gobies, bird eggs, and various fish species were analysed. Samples were collected in the middle and lower reaches of the estuary, the areas known to receive major pollution loads from neighbouring sources. Heavy metals found in the sediments were compared to previous studies. Bottom sediments and organisms surrounding major discharge points showed higher concentrations of pollutants and compared to previous studies, these concentrations seem to be increasing. Due to biomagnification, higher concentrations were generally found in the top predators although certain elements did not show this trend. Some heavy metal concentrations found in the fish exceeded of the food guidelines and may in turn pose a threat for subsistence users of the SRE. There are indications of multiple different pollution sources. Bird eggs had detectable quantities of polychlorinated biphenyls, but its implications need more investigation. / MSc (Zoology), North-West University, Potchefstroom Campus, 2014

Thesis (MSc)--Stellenbosch University, 1981. / ENGLISH ABSTRACT: No abstract available / AFRIKAANSE OPSOMMING: Die aard, omvang en beheer van voelskade by wyndruiwe is ondersoek in die streek Stellenbosch - Simonsberg. Die Mossie (Passer melanurus, Willer) en die Europese spreeu (Sturnus vulgaris, Linnaeus) veroorsaak die meeste voelskade aan.wyndruiwe in die streek. Die kultivars gebruik in die ondersoek Was Chenin blanc, Pint noir, Riesling, Cinsaut, Clairette blanche en Cabernet Sauvignon. Die laagste suiker- en tic.ogsbasuurgehaltes waarby voelskade voorgehom het was onderskeidelik 11,2° Balling en 25,9g per l,- terwyl vreetskade by gemiddelde 12,4°. Balling en 19,1 g per l totale suur begin het. Die belangrikste enkele faktor wat t rol gespeel het by beskadiging was die suikerkonsentrasie. Die patroon van vreetskade oor t wingerdry is bepaal en het getoon dat die eerste 30 stokke aan weerskante van die wingerd die meeste beskadig word. 'n Metode is vasgestel cm die hoeveelheid skade aangerig te bepaal met behulp van tellings van beskadigde korrels in verteenwoordigende wingerdrye. Die skade in die streek is op 2,5% van die totale opbrengs per hektaar bepaal. Die bespuiting van wingerdblokke en alternatiewe buffer-kantrye met die afskrikmiddel metiokarb (Mesurol) teen 'n konsentrasie van 0,1% or genoemde kultivars, asook Muskadel, het onvoldoende beheer gebied. Bespuitings teen hoer konsentrasies word aanbeveel.

Cooperative breeding is a phenomenon whereby breeding and nonbreeding individuals collectively provision young. Nonbreeding group members ("helpers'') may gain indirect and/or direct fitness benefits by breeding in a group, but there has been conflicting evidence regarding the benefits to breeders. In fact, the presence of helpers may sometimes be detrimental to aspects of breeder fitness. For example, in some species of the chiefly Australian genus Malurus, breeding males with helpers have lower within-pair paternity than do males without helpers. Additionally, indirect benefits to breeding males are often limited by low relatedness to their helpers due to high extrapair paternity rates, and helpers often appear to have minimal impact on breeder reproductive success. However, the presence of helpers may allow breeding males to shift their behaviors from guarding and provisioning young to alternative behaviors that affect other components of fitness, such as extraterritory forays (which might increase extrapair mating success) and self-maintenance (which might increase survival). We investigated these possibilities in the facultatively cooperative Red-backed Fairywren (Malurus melanocephalus). Males with helpers spent significantly less time engaging in guarding behaviors and provisioning of young than did those without helpers, but there was no difference in the frequency of extrapair forays nor the number of young sired by males with vs. without helpers. Additionally, the decreased investment in nesting behaviors did not result in consistently higher survival, but may have increased survival in some years. Overall, the results of this study did not suggest any strong direct fitness benefits to breeding males, which may indicate that the costs of retaining helpers are negligible relative to the indirect benefits of helping a potentially related male.

Every year the Eurasian crane travel from northern Africa to northern Europe and Asia. On their migration route they need to rest and often choose places around shallow lakes in agriculture landscapes. During their time in these resting sites the cranes forage in agriculture fields surrounding the lakes, which often cause crop-damage and thereof also financial loses. The last 30 years the population has increased radically, resulting in more extensive crop-damage. This study was set out to gain a better understanding how these migrating cranes choose sites to forage, based on four environment factors: roads, water, buildings, trees and shrub. A study-area in north of Lake Tåkern was selected and during six days in the spring all the cranes in the area were counted and marked on a map. The results showed that the factors affected the occurrence of cranes in the fields. They wanted to be close to shallow water and keep a distance to buildings, roads, trees and shrub. The cranes often spend the night in shallow water and search for food in the area close by to not lose too much energy, which probably was the main reason for the birds to stay close to the water. The distance to buildings and roads suggests that the cranes want to avoid interference from humans and the distance to trees and shrub that they want to have a good awareness of their surroundings. Through this understanding, areas with higher risk to attract groups of cranes can more easily be identified.

Distributional and ecological dynamics of Neotropical migratory birds at stopover sites where they maintain critical fat reserves during migration remain poorly understood in North American aridlands. I examined spatiotemporal abundance and timing of migrants relative to 1) upland and riparian habitats, 2) post-fire landscape mosaics, and 3) phenological synchrony and overlap of migration with tree flowering in southeastern Arizona's Madrean Archipelago (2009-2011), and 4) abundance, habitat breadth, and foraging substrates relative to tree flowering along the Colorado River in southwestern Arizona and northwestern Sonora, Mexico (2000-2003). I explored these dynamics relative to local weather conditions and El Niño Southern Oscillation (ENSO) climate phenomena. In Madrean habitats, migrants showed three non-exclusive responses to high precipitation, snowfall, and low minimum temperatures associated with El Niño in 2010; migration timing adjustments, habitat shifts, and reduced abundances suggesting migration route shifts. Foliage-gleaning insectivores were most abundant in high severity burns, disproportionate to their availability, and decreased with time since fire (TSF); flycatchers were most abundant in low-moderate severity and increased with TSF. Migrant abundance increased with tree flowering. Phenological overlap declined with increasing difference in timing of these events. Overlap was lowest in 2011 in riparian habitat due to low willow (Salix goodinggii) flowering, despite high migrant abundance, but lowest in 2010 in montane conifer, despite high pollen cone production by Douglas-fir (Pseudotsuga meziesii), suggesting temperature limitation of insect abundance at high elevations, but water limitation of plant phenology at lower elevations. Along the Colorado River, migrant abundance and habitat breadth had inverse positive and negative quadratic relationships, respectively. Abundance increased with tree flowering, but only in 2003 during severe drought. Habitat breadth increased with monsoon precipitation. Foraging substrate use tracked flowering, shifting from willow to mesquite (Prosopis sp.); the overlap coincided with peak abundance and narrowest habitat breadth. Maintenance of diverse vegetation and post-fire landscape mosaics in the Madrean Archipelago should benefit migratory bird diversity. Flowering phenology likely provides large-scale cues of local-scale stopover habitat condition associated with interannual climatic variation. Management and restoration of upland habitats and large riparian woody perennials will be critical for migratory bird conservation in aridlands.

There are around 10,426 bird species around the world. Recognizing the bird species for an untrained person is almost impossible either by watching or listening them. In order to identify the bird species from their sounds, there is a need for an application that can detect the bird species from its sound. Time-frequency domain analysis techniques are used to implement the application. We implemented two time-frequency domain feature extraction methods. In feature extraction, a signature matrix which consist of extracted features is created for bird sound signals. A database of signature matrix is created with bird chirps extracted features. We implemented two feature classification methods. They are auto-correlation feature classification method and reference difference feature classification method. An unknown bird chirp is compared with the database to detect the species name. The main aim of the research is to implement the time-frequency domain feature extraction method, create a signature matrix database, implement two feature classification methods and compare them. At last, bird species were identified in the research and the auto-correlation classification method detects the bird species better than the reference difference classification method.

As a prelude to strain selection for domestication and future marker assisted selection, genetic variation revealed by microsatellite DNA was evaluated in yellow perch, Perca flavescens, from four wild North American populations collected in 2003-2004 (Maine, ME; New York, NY; North Carolina, NC; and Pennsylvania, PA), and two captive populations (Michigan, MI; Ohio, OH). For the loci examined, levels of heterozygosity ranged from He = 0.04 to 0.88, genetic differentiation was highly significant among all population pairs, and effective migration ranged from low (Nem = 0.3) to high (Nem = 4.5). Deviation from Hardy-Weinberg 1equilibrium was regularly observed indicating significant departures from random mating. Instantaneous measures of inbreeding within these populations ranged from near zero to moderate (median F = 0.16) and overall inbreeding levels averaged FIS = 0.18. Estimates of genetic diversity, Φ ST and genetic distance were highest between Michigan and all other populations and lowest between New York and Ohio. Genetic differentiation among populations did not correlate with geographic distance. Overall, the patterns of variation exhibited by the captive (Michigan and Ohio) populations were similar to patterns exhibited by the other allegedly wild populations, indicating that the spawning and management practices to date have not significantly reduced levels of genetic variation.

A fragmentação florestal altera a estrutura das paisagens e as relações dos organismos com esta, sendo a movimentação um dos comportamentos mais afetado. Os indivíduos que se deparam com uma paisagem heterogênea, com áreas de habitat e de não-habitat (i.e., matriz), precisam cruzar as matrizes na procura por recursos. A opção de movimento é feita, então, através de uma avaliação dos custos e benefícios que cada área proporciona ao animal. Entre os maiores custos está o risco de predação, que pode variar conforme a estrutura de cada matriz (e.g. cobertura vegetal) e as características de cada espécie (e.g. capacidade de movimentação). Objetivando analisar o efeito de diferentes matrizes (pasto, milho e Eucaliptus) em relação ao risco de predação para a espécie Pyriglena leucoptera (Tamnophillidae) (1) verificamos se há diferenças entre as matrizes na quantidade de um dos principais predadores dessa ave, as aves de rapina, e (2) inferimos a percepção do risco de predação por meio da análise dos padrões de movimentação, realizando experimentos de translocação e monitoramento por radiotelemetria. Os resultados indicaram haver gradação de predadores nas matrizes estudadas: (milho=pasto)> Eucaliptus. O sucesso das aves em alcançar a mata foi mais alto no Eucaliptus, seguido pelo pasto e pelo milho. Os tempos médios de permanência nas matrizes também foram diferentes: (milho=Eucaliptus)>pasto. Os movimentos foram mais retilíneos no pasto e mais tortuosos no milho, enquanto o Eucaliptus mostrou uma situação intermediária. O milho provavelmente é a matriz mais arriscada para a Pyriglena leucoptera, tendo a maior densidade de aves de rapina, menor sucesso de chegada à mata e maior tortuosidade com maior tempo de permanência na matriz dos indivíduos (i.e. maior tempo de exposição ao risco). O pasto parece ser a matriz de risco intermediário, pois apresenta grande quantidade de aves de rapina, mas com animais menos tempo expostos, fazendo trajetos mais retilíneos, e o sucesso foi maior do que no milho. O Eucaliptus é a matriz de menor risco, teve a menor densidade de aves de rapina e o maior sucesso em chegar à mata. O maior tempo de permanência nessa matriz juntamente com a tortuosidade variada, e o maior sucesso de chegada à floresta, podem significar aproveitamento de recursos. Esses resultados ressaltam a importância dos estudos sobre os efeitos de diferentes matrizes no deslocamento das espécies por paisagens fragmentadas, o que afeta processos ecológicos essenciais ligados à permanência das espécies nestas condições. O manejo adequado das matrizes aparece como uma prioridade em projetos de conservação e restauração da biodiversidade nestas paisagens / Forest fragmentation alters landscape structure and its relationship with organisms, and movement is one of the most affected behaviors. Individuals who are faced with an heterogeneous landscape, composed of habitat and non-habitat areas (i.e., matrix), need to cross the non-habitat matrix in the search for resources. The choice of motion is then made by an evaluation of the costs and benefits that each area provides to the animal. Among major costs while moving through the matrix is the risk of predation, which may vary with the structure of each matrix (e.g., vegetation cover) and the behavioral characteristics of each species (e.g. movement capacity). Aiming to analyze the effect of different matrices (pasture, corn and Eucalyptus) in relation to risk of predation for the species Pyriglena leucoptera (Tamnophillidae) we (1) determined if there were differences between matrices in the density of one of the main predators of the bird, birds of prey, and (2) inferred the perceived risk of predation by performing translocation experiments with radiotelemetry monitoring to describe and analyze movement patterns in the matrix. Our results suggested a predation risk gradient in the studied matrices (corn = pasture)> Eucalyptus. The time birds spent in the matrix until reaching a forest patch was also different among matrices (corn = Eucalyptus) > pasture. Movements were straighter over the pasture matrix and more tortuous in the corn matrix, while in the Eucalyptus matrix movment showed an intermediate pattern. The success of birds to reach a forest patch was higher in the Eucalyptus matrix, followed by the pasture and corn matrix. Corn is probably the riskiest matrix for Pyriglena leucoptera, having the highest density of birds of prey, with most tortuous movement patterns and longest time spent in the matrix (i.e., longer exposure to risk) which resulted in less successful arrival to forest patches. The pasture seems to be the matrix of intermediate risk, because despite a large density of birds of prey, birds spent less time exposed to the risk, making more straight paths, which resulted in a higher success of reaching the forest than in the corn matrix. Eucalyptus was the matrix of lowest risk, had the lowest density of birds of prey and the greatest success in reaching the habitat. In this case, however, tortuosity of movement and the long time spent in this matrix did not result in decrease success of reaching a forest patch, this suggests that birds may be using resources (i.e. foraging) while moving through this less-risky matrix. This project highlights the importance of studies that quantify the effects of matrix type on the movement of organisms through fragmented landscapes, which affects essential ecological processes linked to the persistence of species in these conditions. The proper management of matrices appears as a priority for conservation and restoration of biodiversity in these human-modified landscapes