The 2007–2009 financial crisis led to a decrease in consumer and investor confidence worldwide (SARB, 2008:2). Along with the weakened business sentiment and consumer demand, tightened funding conditions in financial markets, increased inflationary pressures, and declining global manufacturing activities, the world economic recession that followed the collapse of the world financial sector led to an estimated wealth destruction of approximately US$50 trillion (SARB, 2008:2; Aisen & Franken, 2010:3; Karunanayake et al., 2010). Apart from this estimate, the International Monetary Fund (IMF) also projected that the global bank balance sheets in advanced countries suffered losses of approximately US$4 trillion during the period 2009–2010 (Aisen & Franken, 2010:3). As a result, investors have become more risk-adverse (Guiso et al., 2013:1), and the consequences of the financial crisis, made insurable profitable investment decisions extremely difficult as market volatility tends to increase during crises periods (Karunanayake et al., 2010; Schwert, 1989:83). With the financial environment in distress, some fund managers consider equities as the preferred asset class to protect the purchasing power of their clients (Ivan, 2013). However, the studies of Ennis and Sebastian (2003) and Nicholas (2004) found evidence that hedge funds will outperform equity markets during a downswing in financial markets. In addition, hedge funds are considered market-neutral due to these investment funds’ unrestricted investment flexibility and more efficient market timing abilities (Ennis & Sebastian, 2003). Hedge funds are also considered to be more unconventional assets for improving portfolio diversification (Lamm, 1999:87), where the variation of investment strategies available in a hedge fund has the ability to satisfy investors with several different risk preferences (Shin, 2012). Still, a number of previous studies have debated conflicting evidence regarding the performance of hedge funds and the persistence in outperforming other markets. This led to the objective of this study; to evaluate the risk-adjusted performance of US and EU hedge funds compared to the associated world equity markets over the 2007–2009 financial crisis. The evidence from this study confirmed the dominance of hedge funds over the CAC 40, DAX, S&P 500 and Dow Jones, from 2004 to 2011, emphasising that the performance of the US and EU hedge funds would overshadow a normal buy-and-hold strategy on the world equity markets under investigation. Overall, the Sharpe-, Sortino-, Jensen’s alpha-, Treynor- and Calmar ratios illustrated that US hedge funds outperformed both EU hedge funds and the associated equity markets over this period. The presence of non-normality among the return distributions led to the use of the Omega ratio as the proper benchmark, which also confirmed the outperformance of US hedge funds over EU hedge funds and associated world equity markets. / MCom (Risk Management), North-West University, Vaal Triangle Campus, 2014

The 2007–2009 financial crisis led to a decrease in consumer and investor confidence worldwide (SARB, 2008:2). Along with the weakened business sentiment and consumer demand, tightened funding conditions in financial markets, increased inflationary pressures, and declining global manufacturing activities, the world economic recession that followed the collapse of the world financial sector led to an estimated wealth destruction of approximately US$50 trillion (SARB, 2008:2; Aisen & Franken, 2010:3; Karunanayake et al., 2010). Apart from this estimate, the International Monetary Fund (IMF) also projected that the global bank balance sheets in advanced countries suffered losses of approximately US$4 trillion during the period 2009–2010 (Aisen & Franken, 2010:3). As a result, investors have become more risk-adverse (Guiso et al., 2013:1), and the consequences of the financial crisis, made insurable profitable investment decisions extremely difficult as market volatility tends to increase during crises periods (Karunanayake et al., 2010; Schwert, 1989:83). With the financial environment in distress, some fund managers consider equities as the preferred asset class to protect the purchasing power of their clients (Ivan, 2013). However, the studies of Ennis and Sebastian (2003) and Nicholas (2004) found evidence that hedge funds will outperform equity markets during a downswing in financial markets. In addition, hedge funds are considered market-neutral due to these investment funds’ unrestricted investment flexibility and more efficient market timing abilities (Ennis & Sebastian, 2003). Hedge funds are also considered to be more unconventional assets for improving portfolio diversification (Lamm, 1999:87), where the variation of investment strategies available in a hedge fund has the ability to satisfy investors with several different risk preferences (Shin, 2012). Still, a number of previous studies have debated conflicting evidence regarding the performance of hedge funds and the persistence in outperforming other markets. This led to the objective of this study; to evaluate the risk-adjusted performance of US and EU hedge funds compared to the associated world equity markets over the 2007–2009 financial crisis. The evidence from this study confirmed the dominance of hedge funds over the CAC 40, DAX, S&P 500 and Dow Jones, from 2004 to 2011, emphasising that the performance of the US and EU hedge funds would overshadow a normal buy-and-hold strategy on the world equity markets under investigation. Overall, the Sharpe-, Sortino-, Jensen’s alpha-, Treynor- and Calmar ratios illustrated that US hedge funds outperformed both EU hedge funds and the associated equity markets over this period. The presence of non-normality among the return distributions led to the use of the Omega ratio as the proper benchmark, which also confirmed the outperformance of US hedge funds over EU hedge funds and associated world equity markets. / MCom (Risk Management), North-West University, Vaal Triangle Campus, 2014

Le nord du système du Courant de Humboldt (NHCS), le long des côtes péruviennes, est l'une des régions océanique les plus productives au monde. Il représente moins de 0.1% de la surface des océans mondiaux mais contribue actuellement à plus de 10% des captures mondiales en poissons, avec l’anchois Engraulis ringens comme espèce emblématique. Comparé aux autres systèmes d’upwelling de bord Est, la forte productivité en poissons ne peut être expliquée par une productivité primaire plus élevée. Par contre, le NCHS est la région où El Niño, et la variabilité climatique en général est la plus notable. D’autre part, les eaux de surface oxygénées recouvrent une zone de minimum d’oxygène extrêmement intense et superficielle. L’objectif principal de ce travail est de mieux comprendre les relations trophiques au sein du NHCS en combinant l'analyse de contenus stomacaux et d'isotopes stables. Cette étude se focalise sur une variété d’organismes allant des bas niveaux trophiques comme le zooplancton aux prédateurs supérieurs (oiseaux et les otaries à fourrure). Elle combine des études de contenus stomacaux ponctuelles et sur le long terme d’espèces clés telles que l’anchois et la sardine Sardinops sagax et une analyse plus globale, basée sur l'utilisation d'isotopes stables et considérant l’ensemble du réseau trophique dans les années récentes (2008 – 2012). Les analyses des contenus stomacaux d'anchois et de sardine ont permis de revisiter l'écologie de ces espèces. En effet, bien que le phytoplancton domine largement les contenus stomacaux en termes d’abondance numérique, le zooplancton est de loin la composante alimentaire la plus importante pour ces deux espèces en termes de carbone. Dans le cas de l’anchois, les euphausiacés contribuent à plus de 67.5% du carbone ingéré, suivis par les copépodes (26.3%). Sélectionner les proies les plus grandes telles que les euphausiacés procure un avantage énergétique pour l’anchois dans cet écosystème où les carences en oxygène imposent de fortes contraintes métaboliques aux poissons pélagiques. La sardine se nourrit de zooplancton plus petit que l’anchois (copépodes plus petits et moins d’euphausiacés). Ainsi, la compétition trophique entre les sardines et les anchois est minimisée dans le NSCH par le partage de la ressource zooplancton selon sa taille, comme cela a déjà été montré dans d’autres écosystèmes. Ces résultats remettent en question la compréhension première de la position des petits poissons pélagiques (zooplanctonophage et non phytoplanctonophage) dans la chaine trophique ce qui implique de reconsidérer le fonctionnement et les modèles trophiques du NCHS. Afin d’obtenir une compréhension plus globale de la position trophique relative des principaux composants du NHCS une approche basée sur des analyses d’isotopes stables (δ13C et δ15N) a été utilisée. Pour ce faire, la signature isotopique d'échantillons de 13 groupes taxonomiques (zooplancton, poissons, calmars et prédateurs supérieurs) prélevés entre 2008 et 2011 a été déterminée. Les valeurs de δ15N obtenues sont fortement impactées par l’espèce, la taille et la latitude. Le long de la cote péruvienne, la zone de minimum d’oxygène devient en effet plus intense et plus superficielle au sud de ~7.5ºS impactant fortement la valeur de δ15N de la ligne de base. Nous avons donc utilisé un modèle linéaire à effet mixte prenant en compte les effets latitude et taille afin de prédire la position trophique relative des composants clés de l’écosystème. Ces analyses isotopiques confirment les résultats issus des contenus stomacaux sur le régime alimentaire de l’anchois et mettent en évidence l’importance potentielle d’une composante souvent négligée de l’écosystème, la galathée pélagique Pleuroncodes monodon. En effet, nos résultats supportent l’hypothèse selon laquelle cette espèce s’alimenterait en partie sur les oeufs et larves d’anchois, menaçant ainsi les premiers stades de vie des espèces exploitées. [...] / The northern Humboldt Current system (NHCS) off Peru is one of the most productive world marine regions. It represents less than 0.1% of the world ocean surface but presently sustains about 10% of the world fish catch, with the Peruvian anchovy or anchoveta Engraulis ringens as emblematic fish resource. Compared with other eastern boundary upwelling systems, the higher fish productivity of the NHCS cannot be explained by a corresponding higher primary productivity. On another hand, the NHCS is the region where El Niño, and climate variability in general, is most notable. Also, surface oxygenated waters overlie an intense and extremely shallow Oxygen Minimum Zone (OMZ). In this context, the main objective of this study is to better understand the trophic flows in the NHCS using both stomach content and stable isotope analyses. The study focuses on a variety of organisms from low trophic levels such as zooplankton to top predators (seabirds and fur seals). The approach combines both long-term and specific studies on emblematic species such as anchoveta, and sardine Sardinops sagax and a more inclusive analysis considering the 'global' food web in the recent years (2008 –2012) using stable isotope analysis.Revisiting anchovy and sardine we show that whereas phytoplankton largely dominated anchoveta and sardine diets in terms of numerical abundance, the carbon content of prey items indicated that zooplankton was by far the most important dietary component. Indeed for anchovy euphausiids contributed 67.5% of dietary carbon, followed by copepods (26.3%).Selecting the largest prey, the euphausiids, provide an energetic advantage for anchoveta in its ecosystem where oxygen depletion imposes strong metabolic constrain to pelagic fish. Sardine feed on smaller zooplankton than do anchoveta, with sardine diet consisting of smaller copepods and fewer euphausiids than anchoveta diet. Hence, trophic competition between sardine and anchovy in the northern Humboldt Current system is minimized by their partitioning of the zooplankton food resource based on prey size, as has been reported in other systems.These results suggest an ecological role for pelagic fish that challenges previous understanding of their position in the foodweb (zooplanktophagous instead of phytophagous), the functioning and the trophic models of the NHCS.Finally to obtain a more comprehensive vision of the relative trophic position of NHCS main components we used stable isotope analyses. For that purpose we analyzed the δ13C and δ15N stable isotope values of thirteen taxonomic categories collected off Peru from 2008 - 2011, i.e., zooplankton, fish, squids and air-breathing top predators. The δ15N isotope signature was strongly impacted by the species, the body length and the latitude. Along the Peruvian coast, the OMZ get more intense and shallow south of ~7.5ºS impacting the baseline nitrogen stable isotopes. Employing a linear mixed-effects modelling approach taking into account the latitudinal and body length effects, we provide a new vision of the relative trophic position of key ecosystem components. Also we confirm stomach content-based results on anchoveta Engraulis ringens and highlight the potential remarkable importance of an often neglected ecosystem component, the squat lobster Pleuroncodes monodon. Indeed, our results support the hypothesis according to which this species forage to some extent on fish eggs and larvae and can thus predate on the first life stages of exploited species. However, the δ13C values of these two species suggest that anchoveta and squat lobster do not exactly share the same habitat. This would potentially reduce some direct competition and/or predation.