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Letteratura scientifica selezionata sul tema "Loligo – Research – South Africa"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 9 febbraio 2022

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Articoli di riviste sul tema "Loligo – Research – South Africa"

Roberts, Michael J., Nicola J. Downey e Warwick H. Sauer. "The relative importance of shallow and deep shelf spawning habitats for the South African chokka squid (Loligo reynaudii)". ICES Journal of Marine Science 69, n. 4 (23 febbraio 2012): 563–71. http://dx.doi.org/10.1093/icesjms/fss023.

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Abstract Roberts, M. J., Downey, N. J., and Sauer, W. H. 2012. The relative importance of shallow and deep shelf spawning habitats for the South African chokka squid (Loligo reynaudii). – ICES Journal of Marine Science, 69: 563–571. It is well known that the spawning grounds of chokka squid Loligo reynaudii lie along the shallow inshore regions of South Africa's south coast. However, egg masses have been found in deeper water on the Agulhas Bank, and hydroacoustic targets deemed to be large aggregations of spawning squid have been identified. The aim of this study was to investigate the extent, depth range, and importance of deep spawning. Trawl data collected during demersal research surveys between Port Nolloth on the west and Port Alfred on the south coast were examined for egg capsules. No spawning was found on the west coast. Data showed that chokka squid preferred the eastern Agulhas Bank for spawning. Spawning occurred not only inshore but also on the mid-shelf extending to depths of 270 m near the shelf edge. Squid egg biomass markedly decreased beyond 70 m, suggesting delineation between the inshore and offshore spawning grounds. Total egg biomass calculations for depths shallower and deeper than 70 m indicated the coastal area to be strongly favoured, i.e. 82 vs. 18%. These results contest the commonly accepted notion that L. reynaudii is an inshore spawner and redefine the spawning grounds to extend across the shelf.

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Lipiński, M. R. "Food and feeding of Loligo vulgaris reynaudii from St Francis Bay, South Africa". South African Journal of Marine Science 5, n. 1 (1 giugno 1987): 557–64. http://dx.doi.org/10.2989/025776187784522513.

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Sauer, W. H. H., Y. C. Melo e W. de Wet. "Fecundity of the chokka squid Loligo vulgaris reynaudii on the southeastern coast of South Africa". Marine Biology 135, n. 2 (5 novembre 1999): 315–19. http://dx.doi.org/10.1007/s002270050629.

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Stuurman, Mariam. "Research Translation in South Africa". Science & Technology Libraries 23, n. 2-3 (1 luglio 2002): 145–50. http://dx.doi.org/10.1300/j122v23n02_18.

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Firer, Colin, e Merle Sandler. "Finance Research in South Africa". Investment Analysts Journal 23, n. 39 (dicembre 1994): 25–44. http://dx.doi.org/10.1080/10293523.1994.11082331.

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Ellis, G. F. R. "Applied Research in South Africa". Science 269, n. 5221 (14 luglio 1995): 149. http://dx.doi.org/10.1126/science.269.5221.149.

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Smale, Malcolm J., Warwick H. H. Sauer e Roger T. Hanlon. "Attempted Ambush Predation on Spawning Squids LoligoVulgaris Reynaudii by Benthic Pyjama Sharks, PorodermaAfricanum, off South Africa". Journal of the Marine Biological Association of the United Kingdom 75, n. 3 (agosto 1995): 739–42. http://dx.doi.org/10.1017/s002531540003914x.

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This first description of behavioural interactions between benthic pyjama sharks Poroderma africanum (Chondrichthyes: Scyliorhinidae) and spawning squids Loligo vulgaris reynaudii (Cephalopoda: Loliginidae) was made from underwater video recordings. The behaviours are described and illustrated to show that the sharks searched for squids in egg beds, then rested there partially hidden and immobile. The pyjama sharks at-tempted to ambush the squids when they approached to lay their eggs after they had apparently habituated to the predators. Although normally nocturnal, the pyjama sharks had emerged by day from caves and cracks in the rocky reef to attack the spawning squids, thereby benefiting from an occasionally available resource.

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Spottiswoode, B. S., e P. D. Carey. "Advancing neuroimaging research in South Africa". South African Journal of Radiology 12, n. 4 (5 marzo 2008): 82. http://dx.doi.org/10.4102/sajr.v12i4.548.

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Ndimande, Bekisizwe S. "Decolonizing Research in Postapartheid South Africa". Qualitative Inquiry 18, n. 3 (23 gennaio 2012): 215–26. http://dx.doi.org/10.1177/1077800411431557.

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This article emanates from an in-depth qualitative study that examined ideological beliefs among Indigenous parents regarding school desegregation and school “choice” policies in South Africa. The author discusses the politics of qualitative research design and methodology along two primary dimensions: decolonizing research and the importance of Indigenous languages in research. First, the author argues that the language used in qualitative interviews should be situated within the larger sociocultural context of the inquiry in order to affirm and reinforce cultural identities of research participants, not just of the researcher. Second, the author contends that decolonizing approaches in research interrupt and interrogate colonial tendencies at multiple levels, thereby challenging traditional ways of conducting qualitative research. Following on Smith, and Mutua and Swadener, and Denzin, Lincoln, and Smith, and others, the author argues that decolonizing approaches and culturally affirming linguistic choices in research have the potential to return marginalized epistemologies to the center.

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Walker, Alexander R. P. "Seven Research Projects for South Africa". Journal of the Royal Society of Medicine 90, n. 7 (luglio 1997): 361–63. http://dx.doi.org/10.1177/014107689709000701.

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Tesi sul tema "Loligo – Research – South Africa"

Downey, Nicola Jean. "The role of the deep spawning grounds in chokka squid (Loligo reynaudi d'orbigny, 1845) recruitment". Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011867.

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It was previously thought that the South African chokka squid Loligo reynaudi is exclusively an inshore, shallow water spawner. Although spawning mostly within shallow bays (<60 m) the presence of squid eggs in trawls at depths up to 130 m indicates this species frequently makes use of deeper spawning areas on the mid-shelf. The extent of mid-shelf spawning (referred to as deep spawning) and the contribution to recruitment has yet to be assessed. Studies have shown mid-shelf bottom temperature to vary considerably from those inshore, suggesting chokka squid spawn in two very different oceanographic environments. Considering these apparent environmental differences, what leads to the mid-shelf environment becoming a suitable spawning habitat? Does a suitable benthic habitat, required for the attachment of egg pods, occur on the mid-shelf? These questions are not only important for determining the extent of deep spawning, but also to the understanding of factors “driving” deep spawning. The fate of deep spawned hatchlings is another unknown. It has been proposed that the main chokka squid inshore spawning grounds are positioned to exploit the net westward currents on the Eastern Agulhas Bank, i.e. paralarvae would be transported west from the hatching site to the cold ridge, an area of high primary and secondary productivity on the Central Agulhas Bank. This concept has come to be known as the Western Transport Hypothesis. Lagrangian ROMS-IBMs (regional ocean model system – individual-based model) predict the net westward transport of paralarvae from both the inshore and deep spawning grounds, to the cold ridge. These simulations were used to investigate the transport of hatchlings to the cold ridge feeding grounds before the exhaustion of yolk reserves. The fate of paralarvae on reaching the feeding grounds has not yet been investigated. This work has contributed new knowledge to our understanding of deep spawning and its role in recruitment. Specific aims of this study were to (1) determine the extent, range and importance of the deep spawning grounds relative to those inshore; (2) investigate the deep spawning ground habitat (Agulhas Bank mid-shelf) morphology and oceanographic environment; (3) determine the transport and survival of deep spawned hatchlings; and (4) investigate the origin and distribution of chokka squid paralarvae on the Agulhas Bank. The extent, depth range and importance of the deep spawning grounds, relative to those inshore was assessed using 23 years of demersal trawl survey data. Data for both the west and south coasts of South Africa were examined for egg capsules. No spawning was found on the west coast. Data showed that chokka squid preferred the Eastern Agulhas Bank for spawning. Spawning occurred not only inshore but also on the mid-shelf extending to depths of 270 m near the shelf edge. The majority of deep spawned eggs however, were found in the depth range 71-130 m. Squid egg density markedly decreased beyond 70 m, suggesting delineation between the inshore and deep spawning grounds. Total egg biomass calculations for depths shallower and deeper than 70 m indicated the coastal area to be strongly favoured, i.e. 82 vs. 18%. These results contest the commonly accepted notion that chokka squid is an inshore spawner and redefine the spawning grounds to extend across the shelf. Apart from an initial study investigating bottom temperature on the mid-shelf, very little is known about the deep spawning habitat. St Francis Bay, a commonly used spawning location, was chosen as a demonstration area for further study. The deep spawning grounds (71-130 m) were mapped and benthic habitat described from underwater video footage. A study investigating cross-shelf bottom conditions was undertaken off Thys Bay. CTD data were used to compare seasonal bottom temperature and oxygen on the St Francis Bay inshore and deep spawning grounds. Squid movement between the two spawning habitats was assessed using filament tagging. Predation and fishing pressure across the spawning grounds was reviewed. The mid-shelf benthic habitat was found to be similar to that inshore and available for spawning. Despite the generally colder bottom temperatures on the mid-shelf, this study showed that bottom temperature in deeper waters can at times be warmer than inshore. Although mid-shelf warming events lasted from a few hours to a number of days, they resulted in similar conditions to those on the inshore spawning grounds. It is likely these events act to expand or shift spawning habitat. The movement of squid between the two spawning habitats makes it possible for them to seek patches of warm bottom water with appropiate substrate. This suggests they are spawning habitat opportunists. Predation and fishing pressure appear to be higher on the inshore spawning grounds. It is feasible that this also forces spawners to seek out more favourable habitat offshore. An individual-based model was used to predict the fate of mid-shelf and inshore hatched paralarvae. Within the model, both the highly productive cold ridge and inshore spawning grounds were considered feeding or nursery areas. Paralarvae were released from six inshore and six deep spawning sites, spanning the coast between Port Alfred and Knysna. All paralarvae not reaching the feeding areas before the exhaustion of yolk-reserves (≤5 days), not retained within the feeding grounds (≥14 days), and not retained on the Agulhas Bank after exiting the feeding grounds were considered lost. This work illustrated the dependence of paralarval transport success on both spawning location and time of hatching, as established in earlier studies. The current IBM has expanded on initial work, emphasizing the importance of the cold ridge and inshore spawning grounds as nursery areas for deep and inshore spawned paralarvae, respectively. This work has highlighted the complex interactions between processes influencing recruitment variability for chokka squid. Possible relationships between periods of highest recruitment success and spawning peaks were identified for both spawning habitats. Based on the likely autumn increase in deep spawning off Tsitsikamma, and the beneficial currents during this period, it can be concluded deep spawning may at times contribute significantly to recruitment. This is particularly true for years where the cold ridge persists into winter. Data on chokka squid paralarval distribution are scarce. Paralarval distribution and abundance, in relation to Agulhas Bank oceanography, was investigated using bongo caught paralarvae and corresponding oceanographic data. Individual-based models (IBMs) were used to predict the origin or spawning site of the wild caught paralarvae, with reference to inshore versus deep spawning. Although failing to predict realistic points of origin, this study provided evidence to support a number of scenarios previously assumed to influence chokka squid recruitment. First is the possible influence of coastal upwelling on the retention, and hence spatial distribution, of paralarvae on the inshore spawning grounds. The second factor thought to impact recruitment is the loss of paralarvae from the Agulhas Bank ecosystem. This study confirmed the removal of paralarvae from the Eastern Agulhas Bank due to Agulhas Current boundary phenomena and resultant offshelf leakage. In addition, data suggested that the formation of the cold ridge could enhance retention on the Central Agulhas Bank, and so prevent offshelf leakage from the Central and Western Agulhas Bank. A synthesis of the main conclusions is presented. Implications of the findings and directions for future research are discussed.

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Downey, Nicola Jean. "The effect of temperature and turbidity on spawning chokka squid, loligo reynaudii, in Eastern Cape waters". Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/945.

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Several studies suggest the environment influences chokka squid catches which are mostly based on the successful formation of inshore spawning aggregations. None of the evidence, however, is direct observation. Acoustic telemetry offers a means to determine the response of spawners to changes in the environment and insight into the behaviour of spawning squid. A hexagonal array of VR2 receivers deployed 500 m apart was deemed to be ideal to monitor the movement patterns of squid on the spawning sites. In isothermic conditions, an area up to 1.28 km2 could be monitored as there was an approximate 50 m overlap in individual VR2 receiver range. In thermocline conditions however, “acoustic dead zones” as wide as 350 m may have existed between VR2 receivers, limiting the performance of this configuration. Similarly benthic turbidity events would also decrease detection range and limit performance. A hexagonal array of VR2 receivers was moored in Kromme Bay on and around active spawning aggregations during the squid fishery closed seasons of November 2003, 2004, 2005 and 2006. Squid were caught on jigs and tagged with V9 acoustic pressure telemetry transmitters. A total of 45 animals were tagged. Presence-absence analysis identified three general behaviours: (1) arrival at dawn and departure after dusk, (2) a continuous and uninterrupted presence for a number of days and (3) presence interrupted by frequent but short periods of absence. Overall, the data suggests frequent migrations between spawning aggregations and offshore feeding grounds. The pressure sensor data showed both males and females stayed persistently near the seabed during the day, but at night, this pattern was broken with common activity higher up in the water column. The squid did not remain exclusively in the water column and regularly made excursions to the seabed. CTD and temperature data indicated the intrusion of a cold bottom layer due to upwelling at the monitored spawning sites on a number of occasions. The formation of spawning aggregations appears to be triggered by upwelling events and spawning behaviour, once initiated, disrupted by upwelling events with a rapid onset, possibly due to an inability to adapt physiologically over such a short time period.

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Olyott, Leonard James Henry. "A description of spatial and temporal aspects of the lifecycle of chokka squid Loligo vulgaris reynaudii on the inshore spawning grounds and Agulhas bank off the South Coast of South Africa". Thesis, Rhodes University, 2002. http://hdl.handle.net/10962/d1005096.

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The chokka squid, Loligo vulgaris reynaudii, is a commercially important species supporting a large, high-value export fishery for South Africa. This study reviewed its population dynamics and reproductive biology. Biological information collected on biannual research cruises from September 1986 to April 1999 on the Agulhas Bank as well as information from commercial vessels operating in the inshore environment collected between April 1988 and July 1989 and again between June 1999 and May 2000 were analysed. Size ranges of juveniles, subadults and adults were calculated and used to determine seasonal distribution and abundance patterns. Based on Gonadosomatic Indices (GSI) and percentages of mature squid in each month, two peak reproductive seasons in summer and winter were identified although mature squid were present all year round. Seasonal peaks in sex ratio were also apparent with males outnumbering females by up to 4:1 in the peak-breeding season. The size at which squid matured, demonstrated both spatial and temporal patterns. Squid caught in spring matured at a smaller size than squid caught in autumn and at successively smaller sizes from west to east across the Agulhas Bank. Size at maturity was highly variable especially in males where “sneaker males” were evident in both seasons. Length-to-weight linear regression revealed significant differences between maturity stages and between sexes. Females demonstrated steeper length-to-weight regression slopes than males in the peak-breeding seasons. Aspects of squid biology pertinent to fishery management were highlighted as well as potential areas where research should be directed in order to develop future stock assessment models.

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Hancke, Lisa. "Dynamics of the Tsitsikamma current, with implications for larval transportof chokka squid (Loligo reynaudii) on the eastern Agulhas Bank". Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/2035.

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Thesis (MTech (Oceanography))Cape Peninsula University of Technology, 2010
The current dynamics along the Tsitsikamma coast is described from a combination of acoustic current measurements. satellite-tracked surface drifters and underwater temperature recordings made between November 2006 and March 2008. The Tsitsikamma coast is largely a Marine Protected Area (MPA) that protects a rich marine biodiversity. The nearshore currents are important in the dispersal of eggs and larvae of many marine species. including the paralarvae of the commercially caught chokka squid. LoNgo reynaudii. Changes in the environment, including the currents. can affect the successful recruitment of chokka squid, and can bring about large annual fluctuations in biomass that creates economic uncertainty in the squid fishery. Results confirm the existence of a predominantly alongshore current off the Tsitsikamma coast. At Middelbank eastward flow was slightly dominant, with a percentage occurrence of 58% vs. 41% westward flow near the surface. The percentage eastward flow decreased with depth, with 41% vs. 58% westward flow near the seabed. At Thyspunt westward and eastward flow occurred at near equal percentages. but westward flow was slightly dominant throughout the water column. The alongshore current was strongest near the surface during eastward flow (maximum = 141 crn.s1: average = 27 crn.s '). while westward surface currents were weaker (maximum velocity = 78 cm.s1: average = 19 crn.s1). Current speed generally decreased with depth and opposing surface and bottom currents, associated with a thermal stratified water column, were occasionally recorded. The nearshore flow regime was characterised by frequent barotropic alongshore reversals that occurred year round. An increase in strong eastward episodes, and opposing surface and bottom currents during spring and summer months have implications for the dispersal of squid paralarvae during the summer and winter spawning seasons. In summer, the combination of strong eastward pulses in the current and upwelling at the capes favoured dispersal onto the midshelf of the Agulhas Bank. In winter, alongshore oscillations without the offshore displacement associated with upwelling. restricted offshore dispersal which caused surface particles to be retained inshore. Drifter trajectories show that both the eastward and westward nearshore current can link the inshore spawning grounds with the nursery grounds, offshore on the central Agulhas Bank; and that passive, neutrally buoyant material in the surface layer can reach the vicinity of the cold ridge in as little as eight days. The wind-driven processes of upwelling and coastal trapped waves (CTWs). and the influence of the greater shelf circulation are discussed as possible driving forces of variability in the currents off the Tsitsikamma coast. The occurrence of coastal trapped waves during thermal stratification appears to drive the jet-like, eastward pulses in the current. and results suggest that the propagation of CTWs may regulate and even enhance upwelling and downwelling along the Tsitsikamma coast.

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Olyott, L. J. H., W. H. H. Sauer e Anthony John Booth. "Spatio-temporal patterns in maturation of the chokka squid (Loligo vulgaris reynaudii) off the coast of South Africa". ICES Journal of Marine Science, 2006. http://hdl.handle.net/10962/d1007930.

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Knowledge of the temporal and spatial characteristics of chokka squid (Loligo vulgaris reynaudii) biology in South African waters is limited, so the possibility of there being a geographically fragmented stock was examined by investigating the distribution of maturity patterns for the species, covering all known spawning areas and using both historical and recent data. Gonadosomatic indices (GSI) varied between year-round consistency and apparent seasonal peaks in both summer and winter; there was no clear spatial pattern. Monthly percentage maturity provided further evidence for two peak reproductive periods each year, although mature squid were present throughout. Sex ratios demonstrated great variability between different areas and life history stages. Male-biased sex ratios were only apparent on the inshore spawning grounds and ranged between 1.118:1 and 4.267:1. Size at sexual maturity was also seasonal, squid maturing smaller in winter/spring than in summer/autumn. Also, squid in the east matured smaller than squid in the west. Although the results from the present study do not provide conclusive evidence of distinct geographic populations, squid likely spawn over a significantly larger area of the Agulhas Bank than previously estimated, and squid on the west coast of South Africa may return to spawn on the western portion of the Agulhas Bank. It remains likely, however, that the east and west coast populations are a single stock and that migration of juveniles to the west coast and their subsequent return as sub-adults is an integral but non-essential and variable part of the life history.

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Joyner, Jessica Mary. "The influence of environmental variability on the catch of chokka, Loligo reynaudii, off the coast of South Africa". Thesis, Rhodes University, 2017. http://hdl.handle.net/10962/32130.

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Globally, cephalopod fisheries are being relied on more heavily due to the depletion of longer-lived teleost species. The South African chokka squid (Loligo reynaudii) fishery is a case in point. Although previously numerous squid were often caught as bycatch, the fishery has officially been in place since 1985. Since the inception of the chokka fishery in South Africa, several studies have investigated the relationship between environmental drivers and annual chokka squid catch, with varying degrees of success. Recently, in 2013, chokka squid catches hit a record low, prompting resurgence in the topic of the squid environment-catch relationship. This study was initiated in an attempt to provide a quantitative relationship between the chokka squid catch and environmental variability, and to build a predictive model that could be used in fisheries management strategies. Historical data were obtained from various sources and included the mean and standard deviation in ocean bottom temperature; the mean and standard deviation in sea surface temperature; the maximum and minimum as well as the variation in wind speed; the mean, predominant and standard deviation in wind direction; the mean and standard deviation in atmospheric pressure; the mean chlorophyll concentration; the number of upwelling events; the hours of easterly winds blowing per day; and two large variation-in-climate indices, namely, the oceanic Nino index and the Antarctic Oscillation index. The monthly catch data were also provided. These data were initially analysed for inter-annual and intra-annual cyclic trends and followed by analysis of the delay in response of catch to the environmental variables, anticipating some impact on the different stages of the chokka life cycle. These lagged data were incorporated into a negative binomial generalised linear model, as well as a generalised additive model, which revealed a strong relationship (r²=0.707) between the catch and environmental variability. The inclusion of all the parameters was necessary; however, the mean bottom temperature and the standard deviation in sea surface temperature were the only parameters that had a significant effect on the catch. These results were used to build a predictive model that indicated that, although the relationship was strong, the ability of the model to predict catch was weak, particularly from the year 2005 onwards.

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Schön, Pieter-Jan. "An investigation into the influence of the environment on spawning aggregations and jig catches of chokka squid Loligo Vulgaris reynaudii off the south coast of South Africa". Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1016369.

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Erratic and highly variable catches in the South African chokka squid Loligo vulgaris reynaudii fishery, cause socio-economic hardship for the industry and uncertainty for resource managers. Catch forecasting can reduce this problem as it is believed that catch variability is strongly influenced by environmental factors. In this study, data were collected at varying temporal and spatial scales. Data for the hourly time-scale study were collected from 1996-1998, aboard commercial vessels, whilst for the longer time-scales, data were extracted for Kromme Bay (a single fishing area) from existing databases (1991-1998) that were comprised of compulsory catch returns and oceanographic data. The environment-catch relationship for chokka squid on the inshore spawning grounds was then investigated using multiple correlation and regression analysis, analysis of variance, contingency table analysis and cross-correlation statistical techniques. This simple, direct, 'black box' statistical approach was relatively successful in developing a predictive capability. On a short time-scale (hourly), the regression model accounted for 32% of the variability in catch, with turbidity the main determinant (13%). On a daily monthly time-scale, the best prediction model was on a monthly scale, accounting for 40% of the variability in catch. The principal determinant, bottom temperature anomaly (11 %), was found to lag one month forward. Seasonal and diel catch variations induced changes in the relative importance of turbidity, water temperature and wind direction on catches. A strong, positive relationship was found between easterly winds (which cause upwelling) and catch, particularly in summer. Catch rates, however, decreased with an increase in turbidity. The correlation between temperature and catch was generally negative, however, higher catches were associated with a temperature range of 13-18°C. Highest catch rates were associated with easterly winds, zero turbidity conditions and sea surface temperatures from 15.0-16.9°C. Selected case studies (in situ observations) suggested that upwelling and turbidity events act as environmental triggers for the initiation or termination of the spawning process, respectively. A holistic approach is required to improve predictive capability of chokka squid abundance. Although short-term predictability remains essential (i.e. hourly-scale), future research should concentrate on long-term prediction models (e.g., monthly time-scales) involving greater spatial variation, which are the most important for management.

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Martins, Rodrigo Silvestre. "Some factors influencing the transport of chokka squid (Loligo reynaudii dOrbigny, 1839) paralarvae off the Eastern Cape, South Africa". Doctoral thesis, University of Cape Town, 2009. http://hdl.handle.net/11427/11400.

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Includes abstract.
Includes bibliographical references (leaves 115-126).
This thesis focuses on these raised concerns and attempts to refine the modelling approach used to test the WTH. This is achieved by investigating squid paralarval survival and their specific gravity using aquarium experiments together with an improved ocean model and IBM. The influence of temperature on yolk utilization was assessed through experimentation. Tank experiments found that yolk utilization rates in chokka squid paralarvae are directly affected by temperature with faster rates at high temperature and slower rates at low temperature.

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Ruth, Damian William. "Research, education and management in South Africa". Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311814.

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Eaton, Elizabeth M. R. "An experimental study of adolescents' identification with South Africa and Africa". Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/10477.

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Bibliography: leaves 127-136.
South African social psychological research on national identity has been limited. The current research aimed to address some of the gaps in the local literature. Two studies were conducted among Grade 11 learners at Cape Town high schools. Study 1 (N=565) included Black African-language speakers, Coloured English-speakers, White Afrikaans-speakers and White English-speakers aged between 16.5 and 18.5. This study was an experimental test of hypotheses based on the principle of 'functional antagonism' within Self-Categorisation Theory (Turner, 1987), as well as on other concepts derived from European and local research. Based on methods used by Cinnirella (1998) and Rutland and Cinnirella (2000), participants were randomly assigned to one of three experimental conditions designed to make national, sub-national, or personal identity salient. The effect of this experimental manipulation on identification with South Africa and with Africa was then assessed across ethnic groups. Study 1 also investigated the relationship between attitudes towards diversity, perceived sub-national group security, and strength of identification with South Africa. Study 2 (N=91) was restricted to Coloured English-speakers within the same age range as in Study 1. Study 2 tested a hypothesis about the relative sensitivity to the experimental manipulation, of alternative measures of identification. No effects for the experimental manipulation of identity salience were found on any of the dependent variables. Significant differences were, however, found between ethnic groups on absolute and relative identification with South African and Africa, as well as on certain pertinent attitudes and beliefs. The result of Study 2 provided a degree of methodological triangulation for Study 1, while also providing additional information about the relative strength of South African, Africa, and nine other social identities. The results are discussed in the light of findings from prior South African research.

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Libri sul tema "Loligo – Research – South Africa"

Wissing, Marié P., a cura di. Well-Being Research in South Africa. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6368-5.

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Fontana, Barbara. The state of migration research in South Africa. Braamfontein: Foundation for Global Dialogue, 1997.

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Coetzee, S. F. Towards an urban research agenda for South Africa. Pretoria: Africa Institute of South Africa, 1994.

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Laher, Sumaya. Psychological Assessment in South Africa: Research and applications. Johannesburg: Wits University Press, 2019.

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Butler-Adam, J. F. Recreation, society, and space in South Africa: Four papers. Durban: Institute for Social and Economic Research, University of Durban-Westville, 1986.

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Brouwers, Ria. South Africa-Netherlands research programme on alternatives in development. The Hague, The Netherlands: Ministry of Foreign Affairs, 2005.

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CSIR. Directory of research organisations and facilities in South Africa. South Africa: Pretoria, 1991.

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Kok, P. C. Development research in South Africa: An inventory of research activities, 1992-1994. Pretoria: HSRC Publishers, 1994.

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Agricultural Research Council (South Africa). ARC: Approach to sustainable agriculture in South Africa. Pretoria: ARC, LNR, 1994.

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Duncan, Reekie W., a cura di. Marketing in South Africa: Decision analysis, theory, and practice. Braamfontein, Johannesburg: Macmillan South Africa, 1985.

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Capitoli di libri sul tema "Loligo – Research – South Africa"

van der Borg, H. H., M. Koning van der Veen e L. M. Wallace-Vanderlugt. "South Africa". In Horticultural Research International, 636–41. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-0003-8_55.

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Sooryamoorthy, R. "Sociological Research: Contemporary Characteristics". In Sociology in South Africa, 105–28. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-40325-0_5.

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Sooryamoorthy, R. "Scientific Research in South Africa". In Transforming Science in South Africa, 135–57. London: Palgrave Macmillan UK, 2015. http://dx.doi.org/10.1057/9781137493071_6.

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Meissner, Richard. "Water Research in South Africa". In Paradigms and Theories Influencing Policies in the South African and International Water Sectors, 1–24. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-48547-8_1.

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Conradie, Francesca. "Medical Research in South Africa". In Health Education in Context, 99–105. Rotterdam: SensePublishers, 2012. http://dx.doi.org/10.1007/978-94-6091-876-6_11.

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Mosavel, Maghboeba, Jodi Winship e Rashid Ahmed. "Participatory Health Research in South Africa". In Participatory Health Research, 239–53. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-92177-8_15.

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Mayer, Claude-Hélène. "Research Methodology". In Combating Wildlife Crime in South Africa, 31–39. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-05891-3_4.

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Lotz-Sisitka, Heila, e Presha Ramsarup. "Green skills research". In Green Skills Research in South Africa, 208–23. New York : Routledge, 2020.: Routledge, 2019. http://dx.doi.org/10.4324/9780429279362-14.

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Onyemelukwe-Onuobia, Cheluchi. "Health research governance in South Africa". In Health Research Governance in Africa, 101–28. Abingdon, Oxon ; New York, NY : Routledge, 2018. | Series: Biomedical law and ethics library: Routledge, 2018. http://dx.doi.org/10.4324/9781315178332-5.

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Ruggunan, Shaun, e R. Sooryamoorthy. "Research in Management: Analysis of Publications". In Management Studies in South Africa, 51–92. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-99657-8_3.

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Atti di convegni sul tema "Loligo – Research – South Africa"

Oyewobi, Luqman Oyekunle, Abimbola Olukemi Windapo e Keith Stone Cattell. "Competitiveness of Construction Organizations in South Africa". In Construction Research Congress 2014. Reston, VA: American Society of Civil Engineers, 2014. http://dx.doi.org/10.1061/9780784413517.210.

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Pretorius, Marco, Jason Hobbs e Terence Fenn. "The User Experience Landscape of South Africa". In the 2015 Annual Research Conference. New York, New York, USA: ACM Press, 2015. http://dx.doi.org/10.1145/2815782.2815807.

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Ramukumba, Margaret, e Felix Ntawanga. "A reflective analysis of the north-south research collaboration in mobile health projects". In 2017 IST-Africa Week Conference (IST-Africa). IEEE, 2017. http://dx.doi.org/10.23919/istafrica.2017.8102407.

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Matshikiza, Sipokazi, e Simon Kiyingi Luggya. "IMPLEMENTATION OF MULTICULTURAL EDUCATION IN SOUTH AFRICA". In 12th annual International Conference of Education, Research and Innovation. IATED, 2019. http://dx.doi.org/10.21125/iceri.2019.1712.

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Vogt, Declan. "A renaissance for mining research in South Africa?" In Fourth International Seminar on Strategic versus Tactical Approaches in Mining. Australian Centre for Geomechanics, Perth, 2011. http://dx.doi.org/10.36487/acg_rep/1108_19_vogt.

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Hauger, Werner K., e Martin S. Olivier. "The state of database forensic research". In 2015 Information Security for South Africa (ISSA). IEEE, 2015. http://dx.doi.org/10.1109/issa.2015.7335071.

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Anyango, Jecton Tocho, e Hussein Suleman. "Teaching Programming in Kenya and South Africa". In Koli Calling '18: 18th Koli Calling International Conference on Computing Education Research. New York, NY, USA: ACM, 2018. http://dx.doi.org/10.1145/3279720.3279744.

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Marais, Mario, e Judy van Biljon. "Social mapping for supporting sensemaking and collaboration: The case of Development Informatics research in South Africa". In 2017 IST-Africa Week Conference (IST-Africa). IEEE, 2017. http://dx.doi.org/10.23919/istafrica.2017.8102336.

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"A Multi-Disciplinary Approach for Excellence in Research and Teaching and Learning in Higher Education". In Nov. 27-28, 2017 South Africa. EARES, 2017. http://dx.doi.org/10.17758/eares.eph1117005.

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Ngulube, Patrick. "MAPPING RESEARCH METHODOLOGICAL PATTERNS USING POSTGRADUATE RESEARCH IN EDUCATION, SOUTH AFRICA". In 11th annual International Conference of Education, Research and Innovation. IATED, 2018. http://dx.doi.org/10.21125/iceri.2018.0465.

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Rapporti di organizzazioni sul tema "Loligo – Research – South Africa"

Research Institute (IFPRI), International Food Policy. The role of CGIAR in agricultural research for development in Africa South of the Sahara. Washington, DC: International Food Policy Research Institute, 2016. http://dx.doi.org/10.2499/9780896292123_15.

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Research Institute (IFPRI), International Food Policy. Changing donor trends in assistance to agricultural research and development in Africa South of the Sahara. Washington, DC: International Food Policy Research Institute, 2016. http://dx.doi.org/10.2499/9780896292123_06.

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Keesstra, Saskia, Angelinus Franke, Henk Wösten e Nester Mashingaidze. Potential role of Conservation Agriculture in South Africa for carbon sequestration for climate mitigation : A provisional research agenda. Wageningen: Wageningen Environmental Research, 2020. http://dx.doi.org/10.18174/526557.

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Homan, Rick, e Catherine Searle. Programmatic implications of a cost study of home-based care programs in South Africa. Population Council, 2005. http://dx.doi.org/10.31899/hiv14.1001.

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Abstract (sommario):

The HIV/AIDS epidemic has meant that an increasing number of chronically ill people need ongoing assistance with care and support. Programs providing home-based care (HBC) services are a key component of the response to HIV/AIDS. However, few programs are using operations research, including cost studies, to decide what services to provide and how to structure their services. In 2004, the Horizons Program undertook a study of six HBC programs from different South African provinces to provide key information to NGOs, government ministries, donors, and the programs themselves to inform decisions about service delivery. The study analyzed the cost of HBC services, the best use of resources, and how well programs are able to meet the needs of beneficiaries and their families. The sample represents programs that operate in rural areas and informal settlements. This brief focuses on the coverage, organization, volume, and costs of the services and on findings from two of the methods of data collection: financial records and service statistics, and interviews with financial officers, program managers, and caregivers.

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Catley, Andy. Commercialising Pastoralist Livestock Systems in East Africa. Institute of Development Studies (IDS), agosto 2021. http://dx.doi.org/10.19088/apra.2021.018.

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Across East Africa’s vast rangelands, pastoralist livestock systems have been commercialising since the early 1900s. Commercialisation has varied widely within and between areas, but now includes substantial livestock exports, regional and cross-border trade, and supply to domestic markets. This policy brief examines some of the key features of pastoralism that affect how commercialisation evolves in pastoralist societies, and why poorer producers often benefit least from new market access. The policy brief draws on a substantial body of research and programme evaluations, and two new APRA research reports on pastoral livestock commercialisation in south-east Ethiopia (Gebresenbet, 2020) and northern Kenya (Roba, 2020).

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Francesco, Petruccione,, Gastrow, Michael, Hadzic, Senka, Limpitlaw, Justine, Paul, Babu Sena, Wolhuter, Riaan e Kies, Carl. Evaluation of Alternative Telecommunication Technologies for the Karoo Central Astronomy Advantage Area. Academy of Science of South Africa (ASSAf), 2021. http://dx.doi.org/10.17159/assaf.2021/0073.

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The National Research Foundation (NRF) requested the Academy of Science of South Africa (ASSAf), on behalf of South African Radio Astronomy Observatory (SARAO) and the Square Kilometre Array (SKA), to undertake an independent and objective evaluation of potential alternative telecommunication technologies for the areas of the Karoo Central Astronomy Advantage Areas (KCAAA). The study encompasses regulatory, public sphere, and technical dimensions to explore options for maintaining the functionality of the telescope while, at the same time, delivering appropriate connectivity solutions for local communities.The objectives of this study are as follows: 1) Assess the technologies currently being, or planning to be, deployed through existing alternative communications programs managed by SARAO, including whether these technologies are comparable with market available technologies that could feasibly be deployed in the KCAAA; and 2) Assessment of current and future telecommunication technologies that may act as suitable replacement and/or improvement (functional and feasible) for existing detrimental technologies, utilised in the KCAAA. This report provides a critical background into the relationship between the SKA and local communities as it relates to ICTs in the area. Based on this understanding, potential technology solutions are proposed to ensure residents of the KCAAA are still afforded valuable access to information and communication technologies (ICTs) within the parameters of affordability, desirability and feasibility.

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Marcos Barba, Liliana, Hilde van Regenmortel e Ellen Ehmke. Shelter from the Storm: The global need for universal social protection in times of COVID-19. Oxfam, dicembre 2020. http://dx.doi.org/10.21201/2020.7048.

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As 2020 draws to a close, the economic devastation caused by the COVID-19 pandemic shows no sign of abating. Without urgent action, global poverty and inequality will deepen dramatically. Hundreds of millions of people have already lost their jobs, gone further into debt or skipped meals for months. Research by Oxfam and Development Pathways shows that over 2 billion people have had no support from their governments in their time of need. Our analysis shows that none of the social protection support to those who are unemployed, elderly people, children and families provided in low- and middle-income countries has been adequate to meet basic needs. 41% of that government support was only a one-off payment and almost all government support has now stopped. Decades of social policy focused on tiny levels of means-tested support have left most countries completely unprepared for the COVID-19 economic crisis. Yet, countries such as South Africa and Bolivia have shown that a universal approach to social protection is affordable, and that it has a profound impact on reducing inequality and protecting those who need it most. In addition to the full paper and executive summary, an Excel file with the data analysed by Oxfam and Development Pathways is available to download on this page, along with an annex on the crisis in Latin America and the Caribbean.

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Status of Postgraduate Research Training in Engineering in South Africa. Academy of Science of South Africa, 2018. http://dx.doi.org/10.17159/assaf.2018/0032.

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Report on a Strategic Approach to Research Publishing in South Africa. Academy of Science of South Africa, 2006. http://dx.doi.org/10.17159/assaf/0038.

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Research Department - Central Bank - General - Banks and Banking - Overseas - South Africa - 1949 - 1951. Reserve Bank of Australia, settembre 2021. http://dx.doi.org/10.47688/rba_archives_2006/16121.

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